Rudy's Traction Engine

[pro-e-geek]

Well, it's been almost a year in recreating a Pro-Engineer CAD model of Rudy's engine from
his original hand drawn plans. (An hour here, 2 hours there & then put away when trout season started up..)

I took this project on for a couple of reasons, the first was that I needed an indoor winter project, & the second was that I wanted to figure out how to create moving mechanisms with the software. I definetly got a better handle on the mechanism part, but got a little hung up with getting the eccentric motion to work out. (I think the CAD model has more HP than my computer does.)

Rudy was a master, his drawings were beautiful & it amazes me how well the fit & finish of his parts in the model are. (But I'm sure that some of you have followed some of the builds of this tractor on this forum or even built them in the past. (I only wish I could view the pictures in the forums for these, I'm "locked out" here at work where I read them during my lunch hour.)

I still need to take care of some details like maybe adding rivets, making the worm for the steering shorter & finish making the gear train run & anything else I missed, but I'm excited to have got this far.

Someday, I hope to have a couple machines & be able to build this, but for now, this is the closest I can get.

Thanks to a couple of you who sent me pictures of his original engine in the past, I'm sorry I don't remember your names off the top of my head, but many thanks,

I've attached an image, I hope it goes through,

Any comments welcome,

John

 

[Aquarius21]

Thanks John, Rudy's traction engine is one of those "dream along with me" shop ideas
I want to pursue when time becomes available... whenever that will be given these
busy days. But thanks for showing us that great 3-D- kind of inspires a
person to want to learn how to learn again about using CAD. ( It's been
a very long time for me. Last time I used two
screens and everything was 2-D.) Thanks, and geat job. Quincy

 

[RDB61]

I’m looking for the cut gear diagrams. The book gives a cut list but no other details. Any help would be appreciated.

 

[johnmcc69]

Rudy gave the parts list in the drawings with the supplier & the gear specifics. I think there are a couple plan sets floating about but after going through those I broke down & bought the book "Building Rudy's Tractor" from Village Press, well worth it just for the pic's & assembly info.

I have to ask what you mean by "Cut gear diagrams" though, do you need the basic gear info (PD, No. of teeth, ETC.) or are you looking for the gear spacing layout? I may be able to help you.

I also remember seeing that some folks who have built this changed the gear ratio to make it run slower or faster but I don't remember the specifics.

John
(Formerly known as "Pro-E-Geek")

 

[RDB61]

Well, it's been almost a year in recreating a Pro-Engineer CAD model of Rudy's engine from
his original hand drawn plans. (An hour here, 2 hours there & then put away when trout season started up..)

I took this project on for a couple of reasons, the first was that I needed an indoor winter project, & the second was that I wanted to figure out how to create moving mechanisms with the software. I definetly got a better handle on the mechanism part, but got a little hung up with getting the eccentric motion to work out. (I think the CAD model has more HP than my computer does.)

Rudy was a master, his drawings were beautiful & it amazes me how well the fit & finish of his parts in the model are. (But I'm sure that some of you have followed some of the builds of this tractor on this forum or even built them in the past. (I only wish I could view the pictures in the forums for these, I'm "locked out" here at work where I read them during my lunch hour.)

I still need to take care of some details like maybe adding rivets, making the worm for the steering shorter & finish making the gear train run & anything else I missed, but I'm excited to have got this far.

Someday, I hope to have a couple machines & be able to build this, but for now, this is the closest I can get.

Thanks to a couple of you who sent me pictures of his original engine in the past, I'm sorry I don't remember your names off the top of my head, but many thanks,

I've attached an image, I hope it goes through,

Any comments welcome,

John


View attachment 43489

I have the diameter of the gears and the pitch. No details on width, shoulders, set screws or any other details. The book mentions a extra paper with details on cutting your own gears. I didn’t get that. I’m sure I can figure it out when I get to that point. It would be handy to have the information now. Thanks for any help you can give.

 

[kwoodhands]

Rudy gives you a phone # to call , this is for the safety valve.
Don't bother as Cole Power Models has been out of business for a while. Rudy's drawing shows a 5/16 x27 thread for the safety valve. If you have not tapped the hole ,wait til you get a safety valve in your hand. I had already tapped the hole .
I tried everywhere to get a safety valve @ 30 lbs pressure and the correct thread.
I wound up making my own safety valve with the help of SteamChick and several others. SteamChick sent me a link to download drawings for the valve. Try a search for this link .
As far as gears go, this was my first time cutting gears.
My gear train meshes perfectly now since I screwed up lots of Acetal . I could not understand why the teeth did not look correct . An example I tried making the pinion gears that had 16 teeth. My incorrect pinions had so many teeth it was hard to count.
I finally realized what I did wrong. My rotary tables manual gives you the correct full turns and partial turns for any given pitch. I read the wrong line, as simple as that.
After cutting gears correctly , all the gears in the train meshed well. The steering gear and the worm were next. I spent several hours trying to figure the worm out. Finally realized the worm is cut on the lathe similar to a screw. I installed the correct gears and cut the worm. I did this on a mini-lathe with a shop made hand crank. First time i used that lathe in a while.
Usually use a 10x22 bench lathe that has metal gears that are greasy. Mini-lathe uses plastic gears, no mess.
After making the gears 3/8" wide I think maybe 1/4" wide will do. Rudy cut his own gears without a hub. He soft solders a hub with a set screw to the brass gears. He does not call this piece a hub, do not recall how he refers to it. My gears are aluminum and the bull gears are Acetal. I prefer to have the hub machined not added later.
Rudy gives you the # of teeth, pitch circle diameter. This is NOT the diameter of the gear blank. To get the blank size, add 2 teeth to the number of teeth and divide by the diametrical pitch (48 in this case). Examples below
120 teeth for bull gear, add 2 - 122. divide by 48 =2.542
This is the blank size.
20 teeth+ 2=22 divide by 48 =.458
16 teeth+2 =18 divided by 48 =.375
There are web sites that gives you same info. Easy enough to get the blank size using method above.
You need to know the working depth of the teeth. this the depth of the cut . I won't go into the addendum and dedendum stuff , both and the clearance are easily found on gear cutting websites.
I suggest you make the first gears out of something inexpensive. I used acetal.
Rudy suggests that gears be cut in two stages. Since the diametrical pitch is 48 , the teeth are small and not necessary to cut in stages.
mike
By the way I got lots of help on this forum for the gear cutting too.
So far I have installed the boiler, took a couple of tries before I got it to test at 60lbs pressure for 30 minutes. This was the first boiler I successfully made.
I built the A 10 Pennsylvania Switcher years ago . I t runs on compressed air as my boiler never tested well. Each time I corrected a leak, the next test leaked somewhere else.
After a week of hard soldering leaks I decided this was not enjoyable any more. I finished the locomotive and it sits on a shelf. Once in a while I run it for the kids in the neighborhood.
mike

 

[johnmcc69]

From what I can see after looking through my books & notes, The gear faces are 1/8" & only the crankshaft pinion & bull gears have hubs (the other gears are idlers & held with screws in the end of the shaft or pressed/glued on. Or as Mike mentioned, using a soldered in hub. The hubs on both the bull/pinion gears are 1/2" Dia. X 1/4" -OAL of gear with hubs is 3/8" lg. & use a 6-32 SS.

I cheated on my CAD model & downloaded the 3D files from SDP/SI, they had most of what was needed. You should check them out.

The worm gear, 20T, .417 PD has a 11/32" Dia. hub with a 5/16" OAL. (no SS), P/N A 1B 6Z48020
The worm, .333 PD .375 OD, has a 1/4" hub with a 3/4" OAL (pilot drilled #47 through both sides) P/N A/C 5-Z48

A fellow on the Model Engine Maker (MEM) did a great write up of his build of Rudy's tractor, you may want to check it out.

Let's see some pic's of what you have so far!

John

 

[RDB61]

From what I can see after looking through my books & notes, The gear faces are 1/8" & only the crankshaft pinion & bull gears have hubs (the other gears are idlers & held with screws in the end of the shaft or pressed/glued on. Or as Mike mentioned, using a soldered in hub. The hubs on both the bull/pinion gears are 1/2" Dia. X 1/4" -OAL of gear with hubs is 3/8" lg. & use a 6-32 SS.

I cheated on my CAD model & downloaded the 3D files from SDP/SI, they had most of what was needed. You should check them out.

The worm gear, 20T, .417 PD has a 11/32" Dia. hub with a 5/16" OAL. (no SS), P/N A 1B 6Z48020
The worm, .333 PD .375 OD, has a 1/4" hub with a 3/4" OAL (pilot drilled #47 through both sides) P/N A/C 5-Z48

A fellow on the Model Engine Maker (MEM) did a great write up of his build of Rudy's tractor, you may want to check it out.

Let's see some pic's of what you have so far!

John

Just in the beginning stages. I guess some of the information I’m looking for is in the book. I do remember reading something about soldering hubs on. Thanks for all the information. I think I’m spending more time making jigs to hold stuff than making parts. I will post some of them as well. Do any of you have pics of the way you held the different pieces. Would be interesting to compare.

 

[RDB61]

Just in the beginning stages. I guess some of the information I’m looking for is in the book. I do remember reading something about soldering hubs on. Thanks for all the information. I think I’m spending more time making jigs to hold stuff than making parts. I will post some of them as well. Do any of you have pics of the way you held the different pieces. Would be interesting to compare.

The first photo is the jig I made to hold the rims and flywheel during drilling and spoke assembly. The second one was used to clean up and mill the ends of the spokes . The last two are the jig to drill and cut the angle on the cleats.

 

[johnmcc69]

It looks like you're doing pretty good with your set ups. It looks like you have this well thought out.

I'm sorry I can't help you in the tooling department, I haven't built this engine.

You had a good set-up for the wheels, I think the rest of it will be pretty easy for you.

Please keep updating us as your build progresses.

john

 

[RDB61]

It looks like you're doing pretty good with your set ups. It looks like you have this well thought out.

I'm sorry I can't help you in the tooling department, I haven't built this engine.

You had a good set-up for the wheels, I think the rest of it will be pretty easy for you.

Please keep updating us as your build progresses.

john

 

[RDB61]

Thanks John. The jig for the cleats worked good. I was able to stack seven at a time drill the holes pin them so they couldn’t shift in the jig and mill the angles with very few burrs to file off . The boiler is a concern. I have never silver soldered anything. I can braze with acetylene, mig and tig weld fairly well. What I’m reading and watching on boilers is a little intimidating. I’m thinking about attempting that next.

 

[johnmcc69]

I started going through my files to see what I could dig up. One of the last projects I worked on was creating the "Proper" sheet metal developments of the many sheet metal parts used. Probably not necessary, but I wanted to play with the sheet metal module of my modeling software & I learned alot doing that. I'm sure, if I build this, I would just cut the parts out & bend them in my bench vise.

Trying to figure out how the whole bunker assy. went together was a little hard to picture in my mind, that is why I created these drawings.

I managed to get through all the sheet metal parts& even added the rivets..

I started working on a new project (a sawmill) & my hard drive crapped out on me...leaving me CADless...

I'll do some more digging to see what I can dig up.

John