Date
1 - 20 of 23
T-Nuts, the easy way
clive_foster@talk21.com
The topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Steven Schlegel
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21@...>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy way
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy way
The topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
wmrmeyers@gmail.com
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Improvise, Adapt, and Overcome.
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
Aphorisms to live by:
Good judgement comes from experience. Experience comes from bad judgement.
SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21@...>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy way
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy way
The topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.Note that I would prefer not to have to do that again, but it's done and works nicely. ;)Bill in OKCWilliam R. Meyers, MSgt, USAF(Ret.)Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know betterOn Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Filing is a useful skill to have. One of the exercises for apprentice machinists was to take a lump of iron, and file it into a 1" cube. Sort of a Sorting Hat for machinists. If you didn't have the patience to do the work, you weren't going to be a good apprentice. If you didn't have or couldn't develop the skill to do it, about the same things. I have not done that particular exercise myself, but Dad taught me to appreciate filing. He called files Mexican Milling Machines, and it was not a pejorative. They could take bits of scrap metal and make useful and necessary things. He admired people like that. He, and my maternal Grandpa taught how to learn how to do stuff.
When my school threw out a bunch of files, I scavenged every one that no one else wanted. Got a bunch of other stuff, too, but there were three nice sharp Mill Bastard files with handles, among many other things. One of each of the big machines...
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Improvise, Adapt, and Overcome.
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
Aphorisms to live by:
Good judgement comes from experience. Experience comes from bad judgement.
SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 01:17:28 PM CST, Nick Andrews <nickjandrews@...> wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.Note that I would prefer not to have to do that again, but it's done and works nicely. ;)Bill in OKCWilliam R. Meyers, MSgt, USAF(Ret.)Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know betterOn Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
mike allen
The old push tabs from Coors cans worked in the dryers ,
a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews
wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Crap. You just reminded me again that I need spare keys for the camper shell on my old pickup truck. I have one useable key that I can find, now. I've taken it to a locksmith, and had no luck finding blanks. May have to try replacing the cylinders in the existing locks, IF I can find something that will interchange. Also need to make a new drawer for my tubular SB lathe stand that I got with my 1941 SB Heavy 10L, and find a lock for it. One drawer and lock was missing when I got it. Somewhere in my info stash is a small booklet from the CIA on make keys...
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Improvise, Adapt, and Overcome.
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
Aphorisms to live by:
Good judgement comes from experience. Experience comes from bad judgement.
SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 01:47:15 PM CST, mike allen <animal@...> wrote:
The old push tabs from Coors cans worked in the dryers ,
a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews
wrote:
Bill, that reminds me of back in college finding open
padlocks on campus for various gates and doors, borrowing
them, opening up the cores and, using needle files, hand
filing key blanks obtained from Walmart or wherever until they
worked. Then, reassemble and return the lock. These were
American locks with swappable cores, easy enough to do. Ended
up with a few keys that opened (and likely still do) about 85%
of the padlocks on campus. So parking lots, steam tunnels,
etc...
Also did the same for laundry machines at some apartments I
lived in briefly where laundry was supposed to be included but
they thought it fine to place coin op machines there, so
definitely NOT included. Holding a small key blank to file to
fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Well that one was a pain, as I had to pick the lock every 90 degree turn as it was one of those threaded rod style. Using a rake, it wasn't bad just lots of repetition at different angles, while sitting on top of the machine. But once the key was made, had a lot of new friends wanting to borrow the laundry key...
On Mon, Feb 27, 2023 at 1:47 PM mike allen <animal@...> wrote:
The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Well at least you're not having to drill into your own safe because you left it sitting in the TX sun for a week and the thermal relocker melted and jammed the super high security combo lock you installed...
On Mon, Feb 27, 2023 at 1:57 PM Bill in OKC too via groups.io <wmrmeyers=yahoo.com@groups.io> wrote:
Crap. You just reminded me again that I need spare keys for the camper shell on my old pickup truck. I have one useable key that I can find, now. I've taken it to a locksmith, and had no luck finding blanks. May have to try replacing the cylinders in the existing locks, IF I can find something that will interchange. Also need to make a new drawer for my tubular SB lathe stand that I got with my 1941 SB Heavy 10L, and find a lock for it. One drawer and lock was missing when I got it. Somewhere in my info stash is a small booklet from the CIA on make keys...Bill in OKCWilliam R. Meyers, MSgt, USAF(Ret.)Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know betterOn Monday, February 27, 2023 at 01:47:15 PM CST, mike allen <animal@...> wrote:The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
wmrmeyers@gmail.com
I cannot doubt that! Thinking of taking an impression of it in wax or clay, then making a casting in brass or aluminum. It's a tiny little thing with 1 narrow and 1 wide groove on one side, and another narrow groove on the opposite side. Only one side is notched. And those notches are worn smooth.
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Improvise, Adapt, and Overcome.
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
Aphorisms to live by:
Good judgement comes from experience. Experience comes from bad judgement.
SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 02:28:13 PM CST, Nick Andrews <nickjandrews@...> wrote:
Well that one was a pain, as I had to pick the lock every 90 degree turn as it was one of those threaded rod style. Using a rake, it wasn't bad just lots of repetition at different angles, while sitting on top of the machine. But once the key was made, had a lot of new friends wanting to borrow the laundry key...
On Mon, Feb 27, 2023 at 1:47 PM mike allen <animal@...> wrote:
The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Have you tried an RV place for some new locks? Usually they aren't the most durable or secure ones used on such things, and you most likely can find replacements online. Or machine a new key blank in brass!
I cannot doubt that! Thinking of taking an impression of it in wax or clay, then making a casting in brass or aluminum. It's a tiny little thing with 1 narrow and 1 wide groove on one side, and another narrow groove on the opposite side. Only one side is notched. And those notches are worn smooth.Bill in OKCWilliam R. Meyers, MSgt, USAF(Ret.)Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know betterOn Monday, February 27, 2023 at 02:28:13 PM CST, Nick Andrews <nickjandrews@...> wrote:Well that one was a pain, as I had to pick the lock every 90 degree turn as it was one of those threaded rod style. Using a rake, it wasn't bad just lots of repetition at different angles, while sitting on top of the machine. But once the key was made, had a lot of new friends wanting to borrow the laundry key...On Mon, Feb 27, 2023 at 1:47 PM mike allen <animal@...> wrote:The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
wmrmeyers@gmail.com
I have not tried an RV place! Thanks for the suggestion! Did look at mobile home stuff, but they're not the same, ether.
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Improvise, Adapt, and Overcome.
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
Aphorisms to live by:
Good judgement comes from experience. Experience comes from bad judgement.
SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 02:38:49 PM CST, Nick Andrews <nickjandrews@...> wrote:
Have you tried an RV place for some new locks? Usually they aren't the most durable or secure ones used on such things, and you most likely can find replacements online. Or machine a new key blank in brass!
I cannot doubt that! Thinking of taking an impression of it in wax or clay, then making a casting in brass or aluminum. It's a tiny little thing with 1 narrow and 1 wide groove on one side, and another narrow groove on the opposite side. Only one side is notched. And those notches are worn smooth.Bill in OKCWilliam R. Meyers, MSgt, USAF(Ret.)Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know betterOn Monday, February 27, 2023 at 02:28:13 PM CST, Nick Andrews <nickjandrews@...> wrote:Well that one was a pain, as I had to pick the lock every 90 degree turn as it was one of those threaded rod style. Using a rake, it wasn't bad just lots of repetition at different angles, while sitting on top of the machine. But once the key was made, had a lot of new friends wanting to borrow the laundry key...On Mon, Feb 27, 2023 at 1:47 PM mike allen <animal@...> wrote:The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
mike allen
My oldest son & his GF at the time took a lock
picking class some where in the Bay Area @ 6-7 years back . I was
the guy at work that they called on to unlock offices & desk's
when folks left their keys at home . Those old master locks that
has the same tabs on both sides of the key were the easiest
padlock to get opened . Now a days I'm not so sure that is a good
characteristic to have
animal
On 2/27/2023 12:27 PM, Nick Andrews
wrote:
Well that one was a pain, as I had to pick the lock every 90 degree turn as it was one of those threaded rod style. Using a rake, it wasn't bad just lots of repetition at different angles, while sitting on top of the machine. But once the key was made, had a lot of new friends wanting to borrow the laundry key...
On Mon, Feb 27, 2023 at 1:47 PM mike allen <animal@...> wrote:
The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
G K
Hey Guys,
First thing, and not that it matters much, but you guys sure do roam off the subject at hand.
Second, did the whole thing on the lathe as it was the most convenient. Turned the T, as well as a new post with imperial threads and an associated washer. (Photos below)
Thanks again to everyone for all the help and advice. Now back to the mill to make a spare set of t-nuts for the mill.
Greg
On Monday, February 27, 2023 at 04:57:22 PM CST, mike allen <animal@...> wrote:
My oldest son & his GF at the time took a lock
picking class some where in the Bay Area @ 6-7 years back . I was
the guy at work that they called on to unlock offices & desk's
when folks left their keys at home . Those old master locks that
has the same tabs on both sides of the key were the easiest
padlock to get opened . Now a days I'm not so sure that is a good
characteristic to have
animal
On 2/27/2023 12:27 PM, Nick Andrews
wrote:
Well that one was a pain, as I had to pick the lock
every 90 degree turn as it was one of those threaded rod style.
Using a rake, it wasn't bad just lots of repetition at different
angles, while sitting on top of the machine. But once the key
was made, had a lot of new friends wanting to borrow the laundry
key...
On Mon, Feb 27, 2023 at
1:47 PM mike allen <animal@...>
wrote:
The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Nice work!
Hey Guys,First thing, and not that it matters much, but you guys sure do roam off the subject at hand.Second, did the whole thing on the lathe as it was the most convenient. Turned the T, as well as a new post with imperial threads and an associated washer. (Photos below)Thanks again to everyone for all the help and advice. Now back to the mill to make a spare set of t-nuts for the mill.GregOn Monday, February 27, 2023 at 04:57:22 PM CST, mike allen <animal@...> wrote:My oldest son & his GF at the time took a lock picking class some where in the Bay Area @ 6-7 years back . I was the guy at work that they called on to unlock offices & desk's when folks left their keys at home . Those old master locks that has the same tabs on both sides of the key were the easiest padlock to get opened . Now a days I'm not so sure that is a good characteristic to have
animal
On 2/27/2023 12:27 PM, Nick Andrews wrote:
Well that one was a pain, as I had to pick the lock every 90 degree turn as it was one of those threaded rod style. Using a rake, it wasn't bad just lots of repetition at different angles, while sitting on top of the machine. But once the key was made, had a lot of new friends wanting to borrow the laundry key...
On Mon, Feb 27, 2023 at 1:47 PM mike allen <animal@...> wrote:
The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Andrei
That's a good looking job you did.
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of G K via groups.io <bug_hunter2000@...>
Sent: Monday, February 27, 2023 6:25 PM
To: southbendlathe@groups.io <southbendlathe@groups.io>; SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: Re: [SouthBendLathe] T-Nuts, the easy way
Sent: Monday, February 27, 2023 6:25 PM
To: southbendlathe@groups.io <southbendlathe@groups.io>; SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: Re: [SouthBendLathe] T-Nuts, the easy way
Hey Guys,
First thing, and not that it matters much, but you guys sure do roam off the subject at hand.
Second, did the whole thing on the lathe as it was the most convenient. Turned the T, as well as a new post with imperial threads and an associated washer. (Photos below)
Thanks again to everyone for all the help and advice. Now back to the mill to make a spare set of t-nuts for the mill.
Greg
On Monday, February 27, 2023 at 04:57:22 PM CST, mike allen <animal@...> wrote:
My oldest son & his GF at the time took a lock picking class some where in the Bay Area @ 6-7 years back . I was the guy at work that they called on to unlock offices & desk's when folks left their keys at home . Those old master locks that has the
same tabs on both sides of the key were the easiest padlock to get opened . Now a days I'm not so sure that is a good characteristic to have
animal
On 2/27/2023 12:27 PM, Nick Andrews wrote:
Well that one was a pain, as I had to pick the lock every 90 degree turn as it was one of those threaded rod style. Using a rake, it wasn't bad just lots of repetition at different angles, while sitting on top of the machine. But once the key
was made, had a lot of new friends wanting to borrow the laundry key...
On Mon, Feb 27, 2023 at 1:47 PM mike allen <animal@...>
wrote:
The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
I believe it's called "thread drift." Might as well get used to it, as it seems to happen everywhere!
And second, very nice job. I had to hunt down your post again, as I hadn't seen the photos yet when I got interrupted by life. Probably a lot faster than hand filing things, too! ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Improvise, Adapt, and Overcome.
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
Aphorisms to live by:
Good judgement comes from experience. Experience comes from bad judgement.
SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 05:25:29 PM CST, G K via groups.io <bug_hunter2000@...> wrote:
Hey Guys,
First thing, and not that it matters much, but you guys sure do roam off the subject at hand.
Second, did the whole thing on the lathe as it was the most convenient. Turned the T, as well as a new post with imperial threads and an associated washer. (Photos below)
Thanks again to everyone for all the help and advice. Now back to the mill to make a spare set of t-nuts for the mill.
Greg
On Monday, February 27, 2023 at 04:57:22 PM CST, mike allen <animal@...> wrote:
My oldest son & his GF at the time took a lock
picking class some where in the Bay Area @ 6-7 years back . I was
the guy at work that they called on to unlock offices & desk's
when folks left their keys at home . Those old master locks that
has the same tabs on both sides of the key were the easiest
padlock to get opened . Now a days I'm not so sure that is a good
characteristic to have
animal
On 2/27/2023 12:27 PM, Nick Andrews
wrote:
Well that one was a pain, as I had to pick the lock
every 90 degree turn as it was one of those threaded rod style.
Using a rake, it wasn't bad just lots of repetition at different
angles, while sitting on top of the machine. But once the key
was made, had a lot of new friends wanting to borrow the laundry
key...
On Mon, Feb 27, 2023 at
1:47 PM mike allen <animal@...>
wrote:
The old push tabs from Coors cans worked in the dryers , a friend told me .
animal
On 2/27/2023 11:16 AM, Nick Andrews wrote:
Bill, that reminds me of back in college finding open padlocks on campus for various gates and doors, borrowing them, opening up the cores and, using needle files, hand filing key blanks obtained from Walmart or wherever until they worked. Then, reassemble and return the lock. These were American locks with swappable cores, easy enough to do. Ended up with a few keys that opened (and likely still do) about 85% of the padlocks on campus. So parking lots, steam tunnels, etc...
Also did the same for laundry machines at some apartments I lived in briefly where laundry was supposed to be included but they thought it fine to place coin op machines there, so definitely NOT included. Holding a small key blank to file to fit was not that pleasant, even filing brass keys.
If all else fails, you can cut a t-nut like I did for my Atlas TH42. Hacksaw, and files. A Sharpie for layout dye, and a scratch awl for marking out. Took me about 4 hours. Didn't even have access to a vise at the time, so held the blank in my hand while cutting and filing on it. Nice sliding fit, no slop.
Note that I would prefer not to have to do that again, but it's done and works nicely. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:Improvise, Adapt, and Overcome.Good judgement comes from experience. Experience comes from bad judgement.SEMPER GUMBY!
Physics doesn't care about your schedule.
The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, February 27, 2023 at 11:42:30 AM CST, Steven Schlegel <sc.schlegel@...> wrote:
Excellent information! Thanks.
Now, if I could just remember how I prepared the t-nut on my SB9...
From: SouthBendLathe@groups.io <SouthBendLathe@groups.io> on behalf of clive_foster@... via groups.io <clive_foster.t21=btinternet.com@groups.io>
Sent: Monday, February 27, 2023 2:40:21 AM
To: SouthBendLathe@groups.io <SouthBendLathe@groups.io>
Subject: [SouthBendLathe] T-Nuts, the easy wayThe topic of getting or making T-nuts to fit QC and block type toolposts is a hardy perennial on forums and internet chat sites.
Reference to the Tooling Dimensions table in "How to Run a Lathe" will show that both sections of the compound Tee slot are nicely sized to accept standard steel bar sections. Two short lengths of appropriate sized bar can easily be screwed and glued together to make a proper full length T-nut that is a very nice fit in the slot. You may need to do a little scraping inside to clear accumulated grot and oil varnish. Possibly with added profanity.
Many years ago when I made several for the pair of 9" and Heavy 10 lathes I once owned I used a pair of countersunk M6 socket hex screws and some sort of Loctite structural adhesive to do the gluing bit. Either M10 or M12 thread on the stud, sorry can't recall which. High strength loctite on all threads of course.
Back in those days I used several 4 way toolpost blocks as a poor boys QC system. Made the blocks by similar screwing and gluing methods from stock plate and bar sections. Alloy was fine for the centre bit. Each block got its own T-nut, stud and tightening lever so swopping was simple matter of half a turn and side out. In retrospect 2 slot blocks would have been just as effective. A fully loaded 4 slot has serious porcupine properties! Disadvantage of simple block posts is the need to shim tools to centre height. As a Brit I can cope just fine with such things. A quick contemplation of relative costs of a QC system to mine in those, pre cheap import days, rapidly resolved any mild resentment. Maybe a decade ago when my last Southbend, the Heavy 10, had been gone for almost as long, it occurred to me that the swopping block system meant I could have simply measured tool heights on the bench with simple jig.
It may be useful to review the whole T-nut situation.
Common advice is to modify what the supplier or make your own from scratch. For the inexperienced making and modifying is harder than it sounds. The two lips must be exactly co-planar if things are to hold properly. If they aren't the slot lips will be distorted and soon things will not hold. An oft ignored detail is that any decent toolpost will have a recess in the centre so the gripping forces are applied towards the outer sides of the post giving decent mechanical advantage. Primarily essential for lathes having a fixed stud where, over time, the centre of the slide around the stud will be pulled up under tightening stresses so only a narrow ring around the stud would actually grip properly on a flat bottom tool post. Common palliative advice is a thin card, pure aluminium or soft copper washer. These compress under stress enough to mostly spread the load.
Similar distortions happen with the more familiar, to SouthBend users, T- slotted compound. The top of the T-slot in the compound of my big P&W Model B was spectacularly distorted by previous owners using a T nut barely bigger than the recess in the base of the Dickson QC post. Resorting to ever longer spanners seemingly obscured the problem. The one in the swarf tray was over 2 ft long. I needed my 4 ft cheater bar to loosen the top nut. Yikes!
In my view the T-nut should extend over the full length of the slot in the compound ensuring all loads are properly distributed minimising the chance of distortion and holding the toolpost firmly without resorting to over tightening and drastic sized spanners. This assumes the top of the toolpost is truly flat. Naturally this is something you will have checked and attended to before putting a new-to-me lathe into service. With the P&W T-slot top now properly flat and a full length T-nut fitted (P&W T-slots are also bar stock size) a moderate pull on a simple tube spanner with a pair of short handles, barely a handspan wide, extending each side keeps the post stable under even the heaviest of cuts.
Hope this helps.
Clive
Yes, thanks for posting the results.
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I (we) would appreciate more project oriented posts.
Jim B,
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Stephen Bartlett
I bought this 9C lathe about 1970, Its only tool holder was the South Bend 8 In 1, I think it
was called. Miserable thing to work with as it sat (and rocked) on two dog point set screws.
I needed a tee nut for the compound rest and had some steel bar available. It was a quick job to hack off two pieces, drill, countersink and tap to fasten them together, then I threaded a piece of scrap rod for the post. I have been using it ever since.
It is not a precision fit, but it has done the job well.
I found a lantern tool holder and hated it. Finally bought an inexpensive post as shown, from Wholesale Tools, along with an assortment of holders. That is about the best thing I have put on the lathe.
It has two different dials because it came with a compound rest but no cross slide or cross slide screw. I bought those from a local SB dealer and by then they had changed. I have had no trouble working with the two different dials.
Steve Bartlett
was called. Miserable thing to work with as it sat (and rocked) on two dog point set screws.
I needed a tee nut for the compound rest and had some steel bar available. It was a quick job to hack off two pieces, drill, countersink and tap to fasten them together, then I threaded a piece of scrap rod for the post. I have been using it ever since.
It is not a precision fit, but it has done the job well.
I found a lantern tool holder and hated it. Finally bought an inexpensive post as shown, from Wholesale Tools, along with an assortment of holders. That is about the best thing I have put on the lathe.
It has two different dials because it came with a compound rest but no cross slide or cross slide screw. I bought those from a local SB dealer and by then they had changed. I have had no trouble working with the two different dials.
Steve Bartlett
mike allen
I'm envious of the large dials you have . I managed to find a
SB owner that was passing forward some of the help he had gotten from
other SB owners & he sold me a large crossfeed dial along with lead
screw & both nuts for $25.00 . I'm hoping to find another guy like
that so I can hopefully get a large dial for m compound . One of these
days .
animal
toggle quoted message
Show quoted text
SB owner that was passing forward some of the help he had gotten from
other SB owners & he sold me a large crossfeed dial along with lead
screw & both nuts for $25.00 . I'm hoping to find another guy like
that so I can hopefully get a large dial for m compound . One of these
days .
animal
On 2/28/2023 3:07 PM, Stephen Bartlett via groups.io wrote:
I bought this 9C lathe about 1970, Its only tool holder was the South
Bend 8 In 1, I think it
was called. Miserable thing to work with as it sat (and rocked) on
two dog point set screws.
I needed a tee nut for the compound rest and had some steel bar
available. It was a quick job to hack off two pieces, drill,
countersink and tap to fasten them together, then I threaded a piece
of scrap rod for the post. I have been using it ever since.
It is not a precision fit, but it has done the job well.
I found a lantern tool holder and hated it. Finally bought an
inexpensive post as shown, from Wholesale Tools, along with an
assortment of holders. That is about the best thing I have put on the
lathe.
It has two different dials because it came with a compound rest but no
cross slide or cross slide screw. I bought those from a local SB
dealer and by then they had changed. I have had no trouble working
with the two different dials.
Steve Bartlett