DRG #168 Major Assemblies


Ric Case
 

Glen I am wanting to try build a couple of EBT ten wheelers and would love to get a copy of the stl files I have two printers with a new one on order !
The new one will print small O gauge
Ric Case
EBT Modeler
Hamilton Ohio
1-513-375-7694
On

On Jul 13, 2022, at 1:26 PM, Glenn Butcher <glenn.butcher@...> wrote:

The boiler ID is a little north of 15mm, so there might be a bit of room for a metal wrapper around a 12mm motor. Yeah, what you see in the picture is quite light. A metal frame is still not out of the question in my project, I'm noodling around with a "butterfly" lasercut o inf the two frame sides attached by a top tab and bent into shape. I think OSHCut could deliver such pre-bent.

For the crosshead guides, I'm thinking of changing the printed part into a CAD subtraction to make slots in the cylinders and hangar into which to slide metal guides. The hangar in the picture is 0.04" thick, doesn't look too bad but still looks bigger than the prototype if you stare at it a bit... I'll find the Nn3 project and look at what he's doing; however I'd like for Shapeways to be an option, not the default.

I'm CAD-ing all this in OpenSCAD script, not for the light-of-heart. I like it because the design is documented, by default. You can see examples of it at my blog of the project: https://glenn.pulpitrock.net/blog/


On 7/13/22 10:52, Mike Conder wrote:
Glenn this looks really good!
Couple of comments:
- wondering about room in the boiler for weights? If 3D printed in resin this will be pretty light, and pulling power is related greatly to balanced weight over the drivers.
- I agree that the valve/rod mechanism just isn’t doable in resin, but those items are perfect for a little Shapeways brass prints. FYI there’s a guy on the Nn3 list that is designing a complete K-class loco for Shapeways brass printing, and his test prints apparently are pretty good. If it can be done in Nn3, HOn3 should be doable.
- so I am interested in the STL files. May also be interested in the CAD files that could be modified, not sure if that’s something you would allow (understand if not) and also don’t remember which 3D design program you’re using.
BTW I’ve designed a steam chest for the old MDC 2-8-0 HOn3 kits to lower the boiler, main issue is making sure the MDC pewter piston rod actually fits the hole. But part of that is that the MDC piston rods are oval, not round, and tend to vary in exact dimensions from kit to kit.
Mike Conder


Glenn Butcher
 

Timely, I printed what I hope is the last iteration of the six parts yesterday, going to test-fit them this morning.  It'll still be a few days, will need to set up the github repository and write some cursory documentation.

I'll let you know when they're available.

Thanks,
g

On 8/16/22 07:24, Ric Case wrote:
Glen I am wanting to try build a couple of EBT ten wheelers and would love to get a copy of the stl files I have two printers with a new one on order !
The new one will print small O gauge
Ric Case
EBT Modeler
Hamilton Ohio
1-513-375-7694
On
On Jul 13, 2022, at 1:26 PM, Glenn Butcher <glenn.butcher@...> wrote:

The boiler ID is a little north of 15mm, so there might be a bit of room for a metal wrapper around a 12mm motor. Yeah, what you see in the picture is quite light. A metal frame is still not out of the question in my project, I'm noodling around with a "butterfly" lasercut o inf the two frame sides attached by a top tab and bent into shape. I think OSHCut could deliver such pre-bent.

For the crosshead guides, I'm thinking of changing the printed part into a CAD subtraction to make slots in the cylinders and hangar into which to slide metal guides. The hangar in the picture is 0.04" thick, doesn't look too bad but still looks bigger than the prototype if you stare at it a bit... I'll find the Nn3 project and look at what he's doing; however I'd like for Shapeways to be an option, not the default.

I'm CAD-ing all this in OpenSCAD script, not for the light-of-heart. I like it because the design is documented, by default. You can see examples of it at my blog of the project: https://glenn.pulpitrock.net/blog/


On 7/13/22 10:52, Mike Conder wrote:
Glenn this looks really good!
Couple of comments:
- wondering about room in the boiler for weights? If 3D printed in resin this will be pretty light, and pulling power is related greatly to balanced weight over the drivers.
- I agree that the valve/rod mechanism just isn’t doable in resin, but those items are perfect for a little Shapeways brass prints. FYI there’s a guy on the Nn3 list that is designing a complete K-class loco for Shapeways brass printing, and his test prints apparently are pretty good. If it can be done in Nn3, HOn3 should be doable.
- so I am interested in the STL files. May also be interested in the CAD files that could be modified, not sure if that’s something you would allow (understand if not) and also don’t remember which 3D design program you’re using.
BTW I’ve designed a steam chest for the old MDC 2-8-0 HOn3 kits to lower the boiler, main issue is making sure the MDC pewter piston rod actually fits the hole. But part of that is that the MDC piston rods are oval, not round, and tend to vary in exact dimensions from kit to kit.
Mike Conder


Mike Conder
 

Ditto, with my single printer and HOn3 ...

Mike Conder

On Tue, Aug 16, 2022 at 7:24 AM Ric Case <ebtmodeler@...> wrote:
Glen I am wanting to try build a couple of EBT ten wheelers and would love to get a copy of the stl files I have two printers with a new one on order !
The new one will print small O gauge
Ric Case
EBT Modeler
Hamilton Ohio
1-513-375-7694
On
> On Jul 13, 2022, at 1:26 PM, Glenn Butcher <glenn.butcher@...> wrote:
>
> The boiler ID is a little north of 15mm, so there might be a bit of room for a metal wrapper around a 12mm motor.  Yeah, what you see in the picture is quite light.  A metal frame is still not out of the question in my project, I'm noodling around with a "butterfly" lasercut o inf the two frame sides attached by a top tab and bent into shape.  I think OSHCut could deliver such pre-bent.
>
> For the crosshead guides, I'm thinking of changing the printed part into a CAD subtraction to make slots in the cylinders and hangar into which to slide metal guides.  The hangar in the picture is 0.04" thick, doesn't look too bad but still looks bigger than the prototype if you stare at it a bit...  I'll find the Nn3 project and look at what he's doing; however I'd like for Shapeways to be an option, not the default.
>
> I'm CAD-ing all this in OpenSCAD script, not for the light-of-heart.  I like it because the design is documented, by default.  You can see examples of it at my blog of the project: https://glenn.pulpitrock.net/blog/
>
>
>> On 7/13/22 10:52, Mike Conder wrote:
>> Glenn this looks really good!
>> Couple of comments:
>> - wondering about room in the boiler for weights?   If 3D printed in resin this will be pretty light, and pulling power is related greatly to balanced weight over the drivers.
>> - I agree that the valve/rod mechanism just isn’t doable in resin, but those items are perfect for a little Shapeways brass prints. FYI there’s a guy on the Nn3 list that is designing a complete K-class loco for Shapeways brass printing, and his test prints apparently are pretty good.  If it can be done in Nn3, HOn3 should be doable.
>> - so I am interested in the STL files.  May also be interested in the CAD files that could be modified, not sure if that’s something you would allow (understand if not) and also don’t remember which 3D design program you’re using.
>> BTW I’ve designed a steam chest for the old MDC 2-8-0 HOn3 kits to lower the boiler, main issue is making sure the MDC pewter piston rod actually fits the hole.  But part of that is that the MDC piston rods are oval, not round, and tend to vary in exact dimensions from kit to kit.
>> Mike Conder
>
>
>






Glenn Butcher
 

Okay, I've posted the first six .stl files here:

https://github.com/butcherg/DRG_168

Under the stl/engine directory you'll find the files.  Here's a picture of what they look like stitched together:



There's also a file integration.scad in the directory with the .stl files; if you install OpenSCAD and open this file in the directory, you'll see the above render, and you can fly around it and disable various parts to see how the others hook up.

Of note is that the frame has a top opening above the front driver, the one I'm thinking of powering.  That might not be the best choice, so the frame may change at that point.  Also, the boiler-firebox does not have an opening above that slot, or the main driver for that matter.

From here, my priority will be to generate "decorations" to make a full static model.  I've already got a full top-line lineup, headlamp, smokestack, etc. except for the generator; I'll post those in a few days.  This doesn't mean I'll totally ignore powering, but rather think it through more carefully, particularly before I order a brass casting of the frame from Shapeways.

If anyone finds things that need changing or improving, let me know and I'll push changes to the repo.


Mike Conder
 

Thanks Glenn, I downloaded the files and really appreciate it!

Mike Conder

Virus-free.www.avg.com


On Tue, Aug 16, 2022 at 4:06 PM Glenn Butcher <glenn.butcher@...> wrote:
Okay, I've posted the first six .stl files here:

https://github.com/butcherg/DRG_168

Under the stl/engine directory you'll find the files.  Here's a picture of what they look like stitched together:



There's also a file integration.scad in the directory with the .stl files; if you install OpenSCAD and open this file in the directory, you'll see the above render, and you can fly around it and disable various parts to see how the others hook up.

Of note is that the frame has a top opening above the front driver, the one I'm thinking of powering.  That might not be the best choice, so the frame may change at that point.  Also, the boiler-firebox does not have an opening above that slot, or the main driver for that matter.

From here, my priority will be to generate "decorations" to make a full static model.  I've already got a full top-line lineup, headlamp, smokestack, etc. except for the generator; I'll post those in a few days.  This doesn't mean I'll totally ignore powering, but rather think it through more carefully, particularly before I order a brass casting of the frame from Shapeways.

If anyone finds things that need changing or improving, let me know and I'll push changes to the repo.


Mysterytrain
 

Good morning, are you planning to print valve gear? I purchased a HOn3 Gem EBT basket case that is missing it's southern valve gear. I would be very interested in a set if you make some up.
Thanks, Ron


Ric Case
 

Ron have you looked at the bowser catalog for replacement valve gear?

Ric Case 
EBT Modeler 
Hamilton Ohio 
1-513-375-7694

On Aug 17, 2022, at 8:22 AM, Mysterytrain via groups.io <mysteryt@...> wrote:

Good morning, are you planning to print valve gear? I purchased a HOn3 Gem EBT basket case that is missing it's southern valve gear. I would be very interested in a set if you make some up.
Thanks, Ron


Bill Lugg
 

Didn't the T-12's have Stephenson valve gear - inside the frame?  I know
the one on the C&TS does.

Bill Lugg

On 8/17/22 06:22, Mysterytrain via groups.io wrote:
Good morning, are you planning to print valve gear? I purchased a HOn3
Gem EBT basket case that is missing it's southern valve gear. I would
be very interested in a set if you make some up.
Thanks, Ron


Glenn Butcher
 

Indeed, all inside the frame.  I hadn't planned on modeling it for #168.

I am working on the crosshead guide/slides/hangar.  I'm going to hand cut/solder the hangar and slides in 0.02" brass, but I have recently completed a 3D model of the crosshead itself, gonna try it by print.  I'll post that here and a couple of weeks, along with the other decorative items I've modeled.

g

On 8/17/22 07:49, Bill Lugg via groups.io wrote:
Didn't the T-12's have Stephenson valve gear - inside the frame?  I know
the one on the C&TS does.

Bill Lugg


On 8/17/22 06:22, Mysterytrain via groups.io wrote:
Good morning, are you planning to print valve gear? I purchased a HOn3
Gem EBT basket case that is missing it's southern valve gear. I would
be very interested in a set if you make some up.
Thanks, Ron




Glenn Butcher
 

Mike, let me know how it goes.  It prints okay in my basement, but it might not in yours :D.  Also, my modeling expectations might be quite low...

On 8/16/22 21:25, Mike Conder wrote:

Thanks Glenn, I downloaded the files and really appreciate it!

Mike Conder

Virus-free.www.avg.com

On Tue, Aug 16, 2022 at 4:06 PM Glenn Butcher <glenn.butcher@...> wrote:
Okay, I've posted the first six .stl files here:

https://github.com/butcherg/DRG_168

Under the stl/engine directory you'll find the files.  Here's a picture of what they look like stitched together:



There's also a file integration.scad in the directory with the .stl files; if you install OpenSCAD and open this file in the directory, you'll see the above render, and you can fly around it and disable various parts to see how the others hook up.

Of note is that the frame has a top opening above the front driver, the one I'm thinking of powering.  That might not be the best choice, so the frame may change at that point.  Also, the boiler-firebox does not have an opening above that slot, or the main driver for that matter.

From here, my priority will be to generate "decorations" to make a full static model.  I've already got a full top-line lineup, headlamp, smokestack, etc. except for the generator; I'll post those in a few days.  This doesn't mean I'll totally ignore powering, but rather think it through more carefully, particularly before I order a brass casting of the frame from Shapeways.

If anyone finds things that need changing or improving, let me know and I'll push changes to the repo.


Mike Conder
 

It may be a while before I can print them, I'm in a production run for the narrow gauge convention this week and muchbof next, then up to Tacoma and not back until mid-September. 

Also playing with resins, for some Siraya to test. 

But thanks again!

Mike Conder

On Wed, Aug 17, 2022 at 9:12 AM Glenn Butcher <glenn.butcher@...> wrote:

Mike, let me know how it goes.  It prints okay in my basement, but it might not in yours :D.  Also, my modeling expectations might be quite low...

On 8/16/22 21:25, Mike Conder wrote:
Thanks Glenn, I downloaded the files and really appreciate it!

Mike Conder

Virus-free.www.avg.com

On Tue, Aug 16, 2022 at 4:06 PM Glenn Butcher <glenn.butcher@...> wrote:
Okay, I've posted the first six .stl files here:

https://github.com/butcherg/DRG_168

Under the stl/engine directory you'll find the files.  Here's a picture of what they look like stitched together:



There's also a file integration.scad in the directory with the .stl files; if you install OpenSCAD and open this file in the directory, you'll see the above render, and you can fly around it and disable various parts to see how the others hook up.

Of note is that the frame has a top opening above the front driver, the one I'm thinking of powering.  That might not be the best choice, so the frame may change at that point.  Also, the boiler-firebox does not have an opening above that slot, or the main driver for that matter.

From here, my priority will be to generate "decorations" to make a full static model.  I've already got a full top-line lineup, headlamp, smokestack, etc. except for the generator; I'll post those in a few days.  This doesn't mean I'll totally ignore powering, but rather think it through more carefully, particularly before I order a brass casting of the frame from Shapeways.

If anyone finds things that need changing or improving, let me know and I'll push changes to the repo.

--
Mike Conder


Mysterytrain
 

Ric, I have looked a PSC. I will give Bowser a shot didn't really think about them as a source. 
Ron


John Stutz
 

Yes Bill

Early D&RG NG locomotive all had Stephenson valve gear, including the K-27s as built.  And at least one photograph shows a K-27 retrofitted with the inboard version of their piston valves that were still driven by inside Stephenson gear.  The D&RGW's use of Walschaerts valve gear on K-27s appears to postdate purchase of the K-28s. I do not believe that D&RGW retrofitted any of their earlier NG power, although C&S did fit one of the former DB&W consolidations with a home designed Walschaerts gear.

Virtually every domestic US locomotive built between 1850 and 1904, Mason's bogies excepted, had Stephenson valve gear.   WP&Y #69 of 1908 may have been the first conventional domestic NG locomotive with Walschaerts valve gear.  Exported NG power with Walschaerts valve gear proceeded it, with New Zealand's Q class Pacifics of 1901 being a prominent early example, but almost certainly not the first. 

The Walschaerts outside valve gear was invented in Belgium in 1844, but did not see significant use in the US until about 1910, following its use on Mallet locomotives from 1904 on.  On the Mallets, as on Mason's bogies, it was used because steam pipes precluded fitting inside Stephenson gear.  Prior to then, US locomotive builders had focused exclusively on the Stephenson inside gear.  For example, J.G.A Meyer's exhaustive "Modern Locomotive Construction" (1892, available online or reprinted), does not even hint that any alternative existed.  Why U.S. builders and buyers persisted with the inside Stephenson gear so late is as much a question for sociologists as technologists.  But by 1910 the advantages, particularly for maintenance, of outside gears were being recognized, and outside gears would soon become the standard for larger locomotives.

John Stutz

On August 17, 2022 6:49 AM Bill Lugg via groups.io < luggw1@...> wrote:

Didn't the T-12's have Stephenson valve gear - inside the frame?  I know
the one on the C&TS does.

Bill Lugg


Earl Knoob
 

From a technical standpoint, Stephenson Valve Gear is superior to Walschearts gear.  The big feature of Stephenson is the variable "lead" in the steam admission when the valve gear is "hooked up" toward center.  As the gear is hooked up, admission of steam into the cylinders occurs earlier and actually before the piston reaches the end of the stroke - hence the term "lead".  To put it into an automotive analogy, it is like advancing the spark on a car's ignition, or more accurately, advancing the camshaft.  So, the faster you went, and the higher you could hook up the valve gear, the better the engine ran.

Walschearts (and Baker Valve gear )has its lead set at the factory through the combining lever (the one that drops from the valve stem down to the crosshead) and the union link that connects it to the crosshead.  Of the all the outside radial valve gears, only Southern Valve gear was capable of creating variable lead.

The biggest problem with Stephenson Gear was as the engines got bigger, the valve gear parts got bigger and heavier.  This was before power reverse gears came into being and the wieght of the eccentric arms, links, etc. were all hanging on the big Johnson Bar in the cab.  It took serious muscles the drag the engine into reverse.  Trying to adjust the valve gear at speed could send the engineer through the front door of the cab.  An articulated with TWO sets of Stephenson valve gear was an impossibility.

This ends our Valve Gear lecture for today....


From: HOn3@groups.io <HOn3@groups.io> on behalf of John Stutz <john.stutz@...>
Sent: Thursday, August 18, 2022 11:59 AM
To: HOn3@groups.io <HOn3@groups.io>
Subject: Re: [HOn3] DRG #168 Major Assemblies
 
Yes Bill

Early D&RG NG locomotive all had Stephenson valve gear, including the K-27s as built.  And at least one photograph shows a K-27 retrofitted with the inboard version of their piston valves that were still driven by inside Stephenson gear.  The D&RGW's use of Walschaerts valve gear on K-27s appears to postdate purchase of the K-28s. I do not believe that D&RGW retrofitted any of their earlier NG power, although C&S did fit one of the former DB&W consolidations with a home designed Walschaerts gear.

Virtually every domestic US locomotive built between 1850 and 1904, Mason's bogies excepted, had Stephenson valve gear.   WP&Y #69 of 1908 may have been the first conventional domestic NG locomotive with Walschaerts valve gear.  Exported NG power with Walschaerts valve gear proceeded it, with New Zealand's Q class Pacifics of 1901 being a prominent early example, but almost certainly not the first. 

The Walschaerts outside valve gear was invented in Belgium in 1844, but did not see significant use in the US until about 1910, following its use on Mallet locomotives from 1904 on.  On the Mallets, as on Mason's bogies, it was used because steam pipes precluded fitting inside Stephenson gear.  Prior to then, US locomotive builders had focused exclusively on the Stephenson inside gear.  For example, J.G.A Meyer's exhaustive "Modern Locomotive Construction" (1892, available online or reprinted), does not even hint that any alternative existed.  Why U.S. builders and buyers persisted with the inside Stephenson gear so late is as much a question for sociologists as technologists.  But by 1910 the advantages, particularly for maintenance, of outside gears were being recognized, and outside gears would soon become the standard for larger locomotives.

John Stutz
On August 17, 2022 6:49 AM Bill Lugg via groups.io < luggw1@...> wrote:

Didn't the T-12's have Stephenson valve gear - inside the frame?  I know
the one on the C&TS does.

Bill Lugg