3/4" Pennsy A3

[SilverSanJuan]

I finally have some work to show.

I'm building a 3/4" scale Pennsy A3 from Kozo's book. I'm starting at the beginning with the tender. Seems the logical thing to do in order to learn the skills to ensure success with the actual locomotive.

So I started out with this:

And, now I have this:

Well, actually now I have three axles done. Just one more and I'll have all the tender wheels complete. I'm ordering material this week to build the frames for the tender trucks.

I also had a little hold up due to my tailstock. As most know, the tailstock on these mini-lathes leave something to be desired. I had to make a new base for mine. The original rocked on the bedways. I could never repeat a setting. Consequently I had some holes that were screwed up. Here is the new base during machining:

I also added a modification to make offsetting the tailstock easier. Don't have a picture of that yet. But, the plan for it can be found on the LMS site.

Having some great fun.
Todd

 

[Mitchg07261995]

this is very cool good luck with the rest of the build

 

[Tin Falcon]

Have the book have not had the heart to start yet. Also thinking about a shay. The semi local museum I sometimes display at has a full sized Shay . The A3 is probably easier. Choices choices.
Good luck on the build.
A journey of hundred miles begins with the first step. A locomotive begining with the firs chips and the first part. Keep up the good work and the posting you just might get me motivated to build mine.
Tin

 

[Herbiev]

Settling in for the journey. Keep the pics coming coming Todd and good luck. Looking great so far

 

[Ryker Carruthers]

Lookin' good!!!!! You are a step ahead of me, I just got the metals list needed for the trucks and hope to get started soon.
Have fun

One question... Did you start with 2 1/4 steel for the wheels or 2 3/8? I wish Kozo would have had a bill of materials after each section or something like that but you cant have everything

 

[SilverSanJuan]

Thanks guys. I'm ready for the long haul. I see every part as a new adventure in learning and experience.

Ryker, I used 2 3/8" 12L14 for the wheels. 2 1/4" wouldn't be good because that is your finished size. Wouldn't give you any room to play with. And, taking off 1/16" all around doesn't take much. I really like the 12L14. It machines really easy and leaves a real nice finish.

Yeah, a Bill of Materials would be nice. But, I'm just going through and making a list as I read through the chapters. This week I'm ordering the brass and bronze for the truck frames and bearings. Plus I'm ordering some steel to make a height gauge. That's another part of this hobby I enjoy, making the tooling.

Todd

 

[Tin Falcon]

Todd that is the attitude . well said enjoy.
Tin

 

[kvom]

Rather than use brass for almost everything, as Kozo did, I'd recommend steel for all the structural parts. Much cheaper, and when done easier to paint. Any added weight will give better traction too.

When it comes time to start the loco, I can recommend using the driver and cylinder castings from Friends Models.

 

[Ryker Carruthers]

Rather than use brass for almost everything, as Kozo did, I'd recommend steel for all the structural parts. Much cheaper, and when done easier to paint. Any added weight will give better traction too.

When it comes time to start the loco, I can recommend using the driver and cylinder castings from Friends Models.

Kvom,
Brass would actually be heavier. It is more dense but in this size it wont make much difference. I plan on using steel as you say.

 

[GWRdriver]

Rather than use brass for almost everything, I'd recommend steel for all the structural parts.

I agree, and I prefer hot rolled steel rather than cold rolled to reduce the tendency to deform when milled. Some folks use flat ground "gauge plate" which IMHO is kind of overkill. It's nice and shiny, and will have less tendency to warp, but it's very expensive.

 

[SilverSanJuan]

Yes, I've been thinking about all that brass. Can get very pricey. And, definitely would rather use the hot rolled steel. Will the hot rolled deform at all when milled? I was under the impression that it wouldn't.

I'm definitely getting the driver and cylinder castings from Friends.

 

[GWRdriver]

Will the hot rolled deform at all when milled?

It can, but I think that will depend upon how it's milled, or rather what shapes will be milled from it. I'm not familiar with the details of the Kozo A3 (except for the boiler) so I can't say what I think it will do, or not.

 

[Ryker Carruthers]

I cant think of anything that requires alot of milling on one piece to the point of deformation. I think the money saved from not using brass could be used to buy the copper for the tank and boiler. May just go galvanized for the tank and coat the inside

 

[kvom]

I used HRS for almost all the steel in my loco. The only CRS I used was in the walk boards. You needs stainless for the piston and valve rods.

I found that, with my local supplier in any case, I needed to size the HRS bars larger than the desired final dimensions. The edges are rounded from the rolling process, so for a piece 1" wide I bought bar stock at least 1-1/8" wide. CRS is accurate dimensionally, so if it doesn't need a lot of machining it can be a reasonable choice, and it doesn't have the mill scale HRS has.

 

[Path]

It can, but I think that will depend upon how it's milled, or rather what shapes will be milled from it. I'm not familiar with the details of the Kozo A3 (except for the boiler) so I can't say what I think it will do, or not.

Harry,

Can you tell me more about the A3 boiler. I've been building the A3 in 3/4" for about 7 years now (off and on, of course ). I'm just starting to gather the wood for the Boiler forms.
Always looking for insight on building ...


Thanks,

Pat H.

 

[GWRdriver]

Hi Pat,
I haven't built an A-3 boiler specifically but I have built variations on the typical Kozo design. Perhaps this should be a new thread, so as not to hijack Todd's thread.

 

[Path]

Harry,

Thanks for quick reply.

I'll start a Build thread when I start the forming the raw stock for the boiler. Then maybe you can advise. Probably a couple of weeks from now.

Thanks,

Pat H.

 

[SilverSanJuan]

Good information on the HRS and CRS. Thanks kvom.

Harry, I look forward to your thoughts on the boiler construction as well. Even though that task is some time away from where I'm at now.

Pat, I look forward to seeing your progress here as well.

 

[SilverSanJuan]

I started on my fourth axle this weekend. The bore on these last two wheels is oversize. These were the first two I made and led to my discovery that my tailstock was bad. Consequently the holes I drilled were off. So I bored them out oversize in hopes that I could salvage them. Well I found that the bore isn't straight through the wheel because it wobbles on the axle. Fortunately I have two spare wheel blanks. So, I started making two new wheels. And, I can still use the axle I started since it can be turned down more to fit the new wheels.

I also ordered some material for the next steps. I'll be using Ralph Patterson's plans to build a height gage.

 

[kvom]

It's easier to fit the axle to the hole than vice-versa. And getting the bore hole straight is preferable with a boring bar than a drill.