how to finess a knob off


Jerry Barr
 

hello all/ need some Ideas how to remove a knob on inner shaft of a horizontal position control /inner is the 10x switch/needed to be removed to access the screws under the thin nameplate panel to remove a board for repair / board is broken /but pulled to hard and shaft now pulled out of control/ hopefully repairable/ its not set screw type knob just the splitshaft type knob still cant pull it from shaft/ any ideas appreciated
thanks Jerry


Brad Thompson <brad.thompson@...>
 

On 6/16/2013 9:28 AM, Jerry wrote:
hello all/ need some Ideas how to remove a knob on inner shaft of a
horizontal position control /inner is the 10x switch/needed to be
removed to access the screws under the thin nameplate panel to remove a
board for repair / board is broken /but pulled to hard and shaft now
pulled out of control/ hopefully repairable/ its not set screw type knob
just the splitshaft type knob still cant pull it from shaft/ any ideas
appreciated
Hello--

By coincidence, I just posted the following suggestion to another
newsgroup. While I doubt that it's applicable to Jerry's predicament,
it may help someone else avoid damaging an expensive or hard-to-find
instrument control knob. [1]

Before you damage a knob, try this:

If the knob in question is fastened to its shaft with a setscrew,
remove the screw and place a droplet of Kroil or other penetrating
oil in the setscrew hole.

Next, obtain a short length (i.e., a few inches) of ribbon cable
as is used in computer disk-drive cables. Using a sharp knife,
separate the conductors in the cable's center, approximately
halfway along the cable.

Push the ribbon cable's opening over the knob and slip
the conductors under the knob between the knob and panel.
Grasp the cable's free ends and gently pull. With any luck,
the knob should slide off without damage.

In contrast to the "pry with a screwdriver" approach,
the ribbon cable applies even pressure to two sides of
the knob.

73--

Brad AA1IP

[1]: note that some knobs are held to their shafts by a
split nut hidden beneath a removable cap set in the
knob's center. Pry off the cap and you'll find a brass
insert that clamps to the control's shaft.


stefan_trethan
 

Heat may help, penetrating oil if certain metals are involved.

I would clamp the shaft and lever the knob off using pressure on the
whole circumfence of the knob, with a washer or a plate with a hole.
If there is a recessed brass or aluminium insert I would use a piece
of tubing or similar sleeve to apply pressure only to the insert, not
the plastic.

ST

On Sun, Jun 16, 2013 at 3:28 PM, Jerry <kj6ntl@yahoo.com> wrote:
hello all/ need some Ideas how to remove a knob on inner shaft of a horizontal position control /inner is the 10x switch/needed to be removed to access the screws under the thin nameplate panel to remove a board for repair / board is broken /but pulled to hard and shaft now pulled out of control/ hopefully repairable/ its not set screw type knob just the splitshaft type knob still cant pull it from shaft/ any ideas appreciated
thanks Jerry



------------------------------------

Yahoo! Groups Links



Don Black <donald_black@...>
 

We used to do a similar think with tight TV knobs. We used a strong length of twine (string - builders line is good) and just wrapped a single turn around the shaft behind the knob. Then pull both ends hard away from the panel and the knob should come off. It stops marking from something like a screwdriver, just look at each situation to make sure it won't do anything bad like snap a thin section knob. usually works a treat.

Don Black.

On 17-Jun-13 12:02 AM, Brad Thompson wrote:
 

On 6/16/2013 9:28 AM, Jerry wrote:
> hello all/ need some Ideas how to remove a knob on inner shaft of a
> horizontal position control /inner is the 10x switch/needed to be
> removed to access the screws under the thin nameplate panel to remove a
> board for repair / board is broken /but pulled to hard and shaft now
> pulled out of control/ hopefully repairable/ its not set screw type knob
> just the splitshaft type knob still cant pull it from shaft/ any ideas
> appreciated
>
Hello--

By coincidence, I just posted the following suggestion to another
newsgroup. While I doubt that it's applicable to Jerry's predicament,
it may help someone else avoid damaging an expensive or hard-to-find
instrument control knob. [1]

Before you damage a knob, try this:

If the knob in question is fastened to its shaft with a setscrew,
remove the screw and place a droplet of Kroil or other penetrating
oil in the setscrew hole.

Next, obtain a short length (i.e., a few inches) of ribbon cable
as is used in computer disk-drive cables. Using a sharp knife,
separate the conductors in the cable's center, approximately
halfway along the cable.

Push the ribbon cable's opening over the knob and slip
the conductors under the knob between the knob and panel.
Grasp the cable's free ends and gently pull. With any luck,
the knob should slide off without damage.

In contrast to the "pry with a screwdriver" approach,
the ribbon cable applies even pressure to two sides of
the knob.

73--

Brad AA1IP

[1]: note that some knobs are held to their shafts by a
split nut hidden beneath a removable cap set in the
knob's center. Pry off the cap and you'll find a brass
insert that clamps to the control's shaft.



Jim <n6otq@...>
 

If you see this in the next few minutes and you have cable TV, put it on Spike NOW and catch the pending episode of "Muscle Car."  They show some ways to get frozen bolts loose, and you might get some ideas.

Otherwise -- the new WD-40 penetrating oil spray is good.  Kroil is excellent.

73
Jim N6OTQ


From: Jerry
To: TekScopes@...
Sent: Sunday, June 16, 2013 8:28 AM
Subject: [TekScopes] how to finess a knob off

hello all/ need some Ideas how to remove a knob on inner shaft of a horizontal position control /inner is the 10x switch/needed to be removed to access the screws under the thin nameplate panel to remove a board for repair / board is broken /but pulled to hard and shaft now pulled out of control/ hopefully repairable/ its not set screw type knob just the splitshaft type knob still cant pull it from shaft/ any ideas  appreciated
thanks  Jerry



------------------------------------

Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/TekScopes/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/TekScopes/join
    (Yahoo! ID required)

<*> To change settings via email:
    TekScopes-digest@...
    TekScopes-fullfeatured@...

<*> To unsubscribe from this group, send an email to:
    TekScopes-unsubscribe@...

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/




Jerry Barr
 

thanks  guys  i did manager to remove the knob  with the oil and washer some piece of plastic was widged in the slot  so the thing cudnt flex at all no on to try repairing my broken board then the control (fingers crossed on that ) its an iwasu scope and 100 mhz 4 channel a little better scan then my 2236 at the high end of frequency band
 
Jerry KJ6NTL

From: Don Black
To: TekScopes@...
Sent: Sunday, June 16, 2013 7:14 AM
Subject: Re: [TekScopes] how to finess a knob off
 
We used to do a similar think with tight TV knobs. We used a strong length of twine (string - builders line is good) and just wrapped a single turn around the shaft behind the knob. Then pull both ends hard away from the panel and the knob should come off. It stops marking from something like a screwdriver, just look at each situation to make sure it won't do anything bad like snap a thin section knob. usually works a treat.

Don Black.

On 17-Jun-13 12:02 AM, Brad Thompson wrote:
 
On 6/16/2013 9:28 AM, Jerry wrote:
> hello all/ need some Ideas how to remove a knob on inner shaft of a
> horizontal position control /inner is the 10x switch/needed to be
> removed to access the screws under the thin nameplate panel to remove a
> board for repair / board is broken /but pulled to hard and shaft now
> pulled out of control/ hopefully repairable/ its not set screw type knob
> just the splitshaft type knob still cant pull it from shaft/ any ideas
> appreciated
>
Hello--

By coincidence, I just posted the following suggestion to another
newsgroup. While I doubt that it's applicable to Jerry's predicament,
it may help someone else avoid damaging an expensive or hard-to-find
instrument control knob. [1]

Before you damage a knob, try this:

If the knob in question is fastened to its shaft with a setscrew,
remove the screw and place a droplet of Kroil or other penetrating
oil in the setscrew hole.

Next, obtain a short length (i.e., a few inches) of ribbon cable
as is used in computer disk-drive cables. Using a sharp knife,
separate the conductors in the cable's center, approximately
halfway along the cable.

Push the ribbon cable's opening over the knob and slip
the conductors under the knob between the knob and panel.
Grasp the cable's free ends and gently pull. With any luck,
the knob should slide off without damage.

In contrast to the "pry with a screwdriver" approach,
the ribbon cable applies even pressure to two sides of
the knob.

73--

Brad AA1IP

[1]: note that some knobs are held to their shafts by a
split nut hidden beneath a removable cap set in the
knob's center. Pry off the cap and you'll find a brass
insert that clamps to the control's shaft.


 

Why are Iwasu scopes so popular on this board? I've never heard of them before but they seem to be quite the hot topic here.


On Mon, Jun 17, 2013 at 1:43 AM, Jerry Barr <kj6ntl@...> wrote:


thanks  guys  i did manager to remove the knob  with the oil and washer some piece of plastic was widged in the slot  so the thing cudnt flex at all no on to try repairing my broken board then the control (fingers crossed on that ) its an iwasu scope and 100 mhz 4 channel a little better scan then my 2236 at the high end of frequency band
 
Jerry KJ6NTL
From: Don Black <donald_black@...>
To: TekScopes@...
Sent: Sunday, June 16, 2013 7:14 AM
Subject: Re: [TekScopes] how to finess a knob off
 
We used to do a similar think with tight TV knobs. We used a strong length of twine (string - builders line is good) and just wrapped a single turn around the shaft behind the knob. Then pull both ends hard away from the panel and the knob should come off. It stops marking from something like a screwdriver, just look at each situation to make sure it won't do anything bad like snap a thin section knob. usually works a treat.

Don Black.

On 17-Jun-13 12:02 AM, Brad Thompson wrote:
 
On 6/16/2013 9:28 AM, Jerry wrote:
> hello all/ need some Ideas how to remove a knob on inner shaft of a
> horizontal position control /inner is the 10x switch/needed to be
> removed to access the screws under the thin nameplate panel to remove a
> board for repair / board is broken /but pulled to hard and shaft now
> pulled out of control/ hopefully repairable/ its not set screw type knob
> just the splitshaft type knob still cant pull it from shaft/ any ideas
> appreciated
>
Hello--

By coincidence, I just posted the following suggestion to another
newsgroup. While I doubt that it's applicable to Jerry's predicament,
it may help someone else avoid damaging an expensive or hard-to-find
instrument control knob. [1]

Before you damage a knob, try this:

If the knob in question is fastened to its shaft with a setscrew,
remove the screw and place a droplet of Kroil or other penetrating
oil in the setscrew hole.

Next, obtain a short length (i.e., a few inches) of ribbon cable
as is used in computer disk-drive cables. Using a sharp knife,
separate the conductors in the cable's center, approximately
halfway along the cable.

Push the ribbon cable's opening over the knob and slip
the conductors under the knob between the knob and panel.
Grasp the cable's free ends and gently pull. With any luck,
the knob should slide off without damage.

In contrast to the "pry with a screwdriver" approach,
the ribbon cable applies even pressure to two sides of
the knob.

73--

Brad AA1IP

[1]: note that some knobs are held to their shafts by a
split nut hidden beneath a removable cap set in the
knob's center. Pry off the cap and you'll find a brass
insert that clamps to the control's shaft.




Jerry Barr
 

i hadnt seen anyone else mention them but me /just cause no one has banned me for it Yet! and hopefully wont/ i do have three of the teks/ but they work for now/
 
Jerry KJ6NTL

From: cheater00 .
To: TekScopes@...
Sent: Sunday, June 16, 2013 11:59 PM
Subject: Re: [TekScopes] how to finess a knob off
 
Why are Iwasu scopes so popular on this board? I've never heard of them before but they seem to be quite the hot topic here.
On Mon, Jun 17, 2013 at 1:43 AM, Jerry Barr <kj6ntl@...> wrote:
thanks  guys  i did manager to remove the knob  with the oil and washer some piece of plastic was widged in the slot  so the thing cudnt flex at all no on to try repairing my broken board then the control (fingers crossed on that ) its an iwasu scope and 100 mhz 4 channel a little better scan then my 2236 at the high end of frequency band
 
Jerry KJ6NTL
From: Don Black <donald_black@...>
To: TekScopes@...
Sent: Sunday, June 16, 2013 7:14 AM
Subject: Re: [TekScopes] how to finess a knob off
 
We used to do a similar think with tight TV knobs. We used a strong length of twine (string - builders line is good) and just wrapped a single turn around the shaft behind the knob. Then pull both ends hard away from the panel and the knob should come off. It stops marking from something like a screwdriver, just look at each situation to make sure it won't do anything bad like snap a thin section knob. usually works a treat.Don Black.On 17-Jun-13 12:02 AM, Brad Thompson wrote:
 
On 6/16/2013 9:28 AM, Jerry wrote:> hello all/ need some Ideas how to remove a knob on inner shaft of a> horizontal position control /inner is the 10x switch/needed to be> removed to access the screws under the thin nameplate panel to remove a> board for repair / board is broken /but pulled to hard and shaft now> pulled out of control/ hopefully repairable/ its not set screw type knob> just the splitshaft type knob still cant pull it from shaft/ any ideas> appreciated>Hello--By coincidence, I just posted the following suggestion to anothernewsgroup. While I doubt that it's applicable to Jerry's predicament,it may help someone else avoid damaging an expensive or hard-to-findinstrument control knob. [1]Before you damage a knob, try this:If the knob in question is fastened to its shaft with a setscrew,remove the screw and place a droplet of Kroil or other penetratingoil in the setscrew hole.Next, obtain a short length (i.e., a few inches) of ribbon cableas is used in computer disk-drive cables. Using a sharp knife,separate the conductors in the cable's center, approximatelyhalfway along the cable.Push the ribbon cable's opening over the knob and slipthe conductors under the knob between the knob and panel.Grasp the cable's free ends and gently pull. With any luck,the knob should slide off without damage.In contrast to the "pry with a screwdriver" approach,the ribbon cable applies even pressure to two sides ofthe knob.73--Brad AA1IP[1]: note that some knobs are held to their shafts by asplit nut hidden beneath a removable cap set in theknob's center. Pry off the cap and you'll find a brassinsert that clamps to the control's shaft.