Once of life’s many mysteries is how keyways get cut inside axle holes.  Thanks to my Shay project, I got to learn this neat skill recently.  First, I had to order a broach, sleeve, and shim from www.mcmaster.com.  One of my favorite websites with a great interface for ordering one of their 400,000 products.

A broach looks like a thick saw blade and cuts by being pushed through a sleeve.  The brand I used was duMONT and you can see a picture here.

Apparently an Arbor Press is typically used to push the broach through the sleeve cutting a little bit with each passing tooth of the broach but on Nelson’s website he seemed to use a hydraulic press.  Since I needed one anyway to assemble the wheels and axles, I waited until one went on sale at Harbor Freight and used what seems to have become a weekly 20% off coupon to get one a great discount.

Here is the press and broach in action.

It takes too passes to cut the complete keyway.  For the second pass a shim is inserted behind the broach.  The final keyway size is 3/16″ x 3/16″ so each pass cuts roughly 3/64″.  It is fairly simple process but I was nervous that the press wasn’t pushing straight down due to the slop in the press.  A precision machine it is not.  Perhaps this is why an Arbor Press is typically used.

The finished keyway -

Definitely not your Grandmother’s broach.

One more wheel to final and one more faced, drilled, bored, and reamed.  I love having a lathe that will drill 1/2 inch holes like nothing.  A hole that size on my mini-lathe was a real ordeal.  Since the holes need to be reamed to .625 (5/8″ inch), I drill to .5, bore to .615, then ream to .625.

Cast iron is so messy and tough that’ll I’ll be happy to get back to cutting steel.  The cast iron powder is very hard to clean from hands and I often go to my job as a software development manager looking like I am moonlighting as an auto mechanic in the evenings.

The goal is to keep working through all eight wheels on hand until they are done.  It is a holiday weekend, so hopefully I’ll get some extra basement time this weekend.

I tend to jump around a little bit as I am machining parts when I can get away with it.  Typically though you try to do things in bulk so you can be efficient and accurate by reusing the same setup and tool settings.  Tonight I felt like turning a wheel down to its final dimensions so I did.  I had previously completed the center hole drill, bore, and ream as well as facing to the appropriate width and turning the outer dimension.  Before I did all of that the rough wheel casting looked like this:

Each Shay wheel is approximately 4″ in diameter.  This is what the wheel looked like when I started this evening.  I had to also create a stub axle to mount the wheel .  It is important that once the wheel is mounted to complete all turning before removing the wheel as it is impossible to mount it exactly the same again.

2 and a half hours later I had the wheel turned.  The tread is at a 2 degree angle and the flange has 10 degree slopes on the sides which is quite time consuming.  There are these things called IBLS wheel standards that must be followed in order to run on club track.  Fun little things like the flange maximum width is .156, flange depth .187, and the radius between the tread and flange is .094 radius plus or minus .015.  Lots of calculating and checking to make sure you have a legal wheel.  I am pretty sure I hit the standards but I might be close on the radius.

The final step was to round the flange and front edge with a file.  I am sure my next one will go much faster.

Some of you are probably confused about what I have been up to.  The last few posts have been out of context so I thought I would backup and explain what I am working on.  Most of the posts on this website were previously about an O Scale Logging Railroad I was building that was loosely modeled on the West Side Lumber Company.  After about six months of working on it pretty steady I went into a holding pattern to work on a live steam shay designed to run on 3.5″ track.  You can see some of work in these posts:

Live Steam

Shay Wheels Completed

Shay Progress as of January 2009

Along the way I learned how to silver solder, use a lathe, mill, and various other metal working skills as well as acquired various tools.  It wasn’t really what I wanted though as it was just too small for my tastes.  I really wanted a 7.5″ gauge live steam shay.  While the track is only slightly more than twice as wide the mass and volume were 8 times.  So using castings from Ken Schroeder at www.shaylocomotive.com, I got started on what i really wanted.  This was about April of 2009.

Nelson Riedel created a website that chronicled his journey through the construction process and has been an endless source of inspiration.  He probably wonders why that one IP has been visiting his site so often.  Here is a picture of him on his Shay so you can see the scale:

I have also found there is a club, Colorado Live Steamers, about 30 miles away from the house that I can join and run my locomotive when done.  I hope to visit soon on a run day to meet some of the members and see the facilities.  Actually running the locomotive seems a long way off though.

One thing that had to be done though was get a much bigger lathe capable of turning the bigger pieces.  I got a Grizzly 10″ metal lathe and wow is it nice.  The old Harbor Freight 7″ lathe seems like a toy but it was a great learning tool.  The only bad thing about the Grizzly was wrestling the 450 pounds into the basement.  Thank god for walkouts.

It does seem to attract a mess.

With the lathe and the mini-mill I got to work on my Shay Trucks.  Lots of milling, drilling, and tapping.

Oh yeah, and heating, bending, welding, and grinding.  I am a terrible welder.  Must be my Dad’s fault.

The axles are just sitting in place without the wheels which haven’t been finished.  Each end of the axle rides in a ball bearing.  Very smooth rolling at this point.

Lots of parts waiting their turn on the lathe, welder, mill or simply to be assembled.

There, now that we are caught up I can provide updates on the details as they come together.  As you saw from last night’s post I am working on finishing up the trucks by building the spring planks.  Other things left to be done include turning the wheels to the final profile, turning the gears down to the final dimensions, cutting keyways, and pressing the wheels onto the axles.  Since I am building a 3 truck shay and I only have 2 trucks worth of castings I will also need to repeat a lot of the steps that got me here.  Good thing I am relatively young.

This evening I created a template and spot faced the top of the bottom spring plank for one of the Shay trucks.  The plank itself was made by welding two 1 1/4″ C-Channels together with a 1/2″ x 3/16″ spacer on the top and bottom.  The welding and grinding was a painful experience and confirmed my thought that I will need to either purchase a steel boiler made by an expert or construct a copper boiler with silver soldering.  I am much better at silver soldering.

The overall assembly is about 11 inches long.  Each of the spot faces will hold a spring and combined with the top plank is what will allow the truck to maintain traction on the track.

In other exciting news, the main gears arrived today.  They need quite a bit of machining but eventually they will be attached to the wheels and really give the Shay its unique character.  Here is a drawing of a real Shay Truck and you can see the full size spring plank beneath the row of springs in the center.

Here is a picture of a real Shay I got to experience several times when I lived in Monterey California.  Roaring Camp and Big Trees railroad is located in Santa Cruz California.

Only two more bottom planks and three more top planks to go!  Who knew making a steam engine was so much work?

No, I didn’t quit trains. I have actually made some great progress on a 1 1/2″ scale, 7 1/2″ gauge Shay.  I just haven’t shared.

I am also trying out publishing from my iPhone.

I have been plugging along on the Shay albeit slowly.  Axles were machined for the wheels and the gears were obtained, machined, and attached to the right side wheels.

This picture will make more sense once the rest of the trucks are built.  This pieces is the center of the truck.  One axle will go on each side of it and this is attached to the frame.  It is sprung to allow the truck to follow the normal track undulations.  Brass is easier to machine but is much more expensive then normal steel.  The end pieces where particularly a fun machining exercise and it was a challenge to rely on the X, Y, and Z axis scales to determine how deep and how far to cut.  The blue dye is used for ease of making and reading the layout markings.

While awaiting some more materials for the trucks, I have began machining the parts and assembling the frame components.

The current body of work is contained in the picture below.  I may have to revise my year estimate to two based on progress.  The good news is that it has been a fun and interesting project.  I enjoy the stolen hours turning a hunk of raw metal into something functional.

The O scale layout has not received much love lately but these things tend to go in cycles.  With the football seasons winding down and winter settling in for the long haul, expect to see more updates soon.

After about six weeks of turning metal, silver soldering, and more turning I finally have 8 beautiful wheels for my Shay Locomotive.  In the course of that time I had to learn how to do things use the lathe accurately, silver solder, bore, and ream.

Here is a profile picture.  Kozo’s book was amazing and walks you through it step by step.  Even an amatuer can get good results.  Are they perfect?  No, far from it but I am happy with them for my first effort.

For those that haven’t seen 3/4″ scale live steam before, here is a picture of the wheels next to my friend, “Harvest Moon”.

The steps were something like this:

1. Turn rims from a big piece of 2.5″ steel rod.
2. Face hubs to width from 7/8″ steel rod.
3. Cut 48 little spokes from steel bar.
4. Drill, tap, and mill 48 little spokes.  (2 broken taps)
5. Attach rim, spokes, and hub to fixture for silver soldering.
6. Flux and silver solder.  Fix many problems by cleaning, fluxing, and resoldering.  The worst wheel took about 8 iterations.  The best wheel was done in one.
7. Face entire wheel to width.
8. Bore and ream center holes.
9. Turn tread to 3 degrees.
10. Turn flange to 10 degrees on each side and file round.