Need advice on keyway for train wheel

[SE18]

Hi all,

I've got three 2-foot gauge kiln cars, one of which I'm going to turn into a locomotive for my railway. I've dissassembled them to clean out the gunk in the bearings, as they've been sitting for a decade in a farmer's field rusting away.

The problem I see, in turning one of them into a locomotive is the way the wheels are fitted to the axles. They are lightly pressed over an upset axle that has some gouges to friction hold it. In fact, they're so lightly pressed that I pulled the wheels off by hand. It's a spindle axle, meaning the whole thing turns.

The idea is to belt or chain drive the axles. The torque produced would likely make the wheels slip on their axles.

The first idea that came to mind is to create a keyway in the axle and wheel and key them all in place. I have a tiny hobby mill and a 9" SBA lathe and 2 drill presses. The axle could easily (I think?) be milled for the keyway but the wheel would be harder.

Perhaps the wheel could be mounted on the drill press and a broach could create the keyway by manually running it in and out (of course without any power to the DP).

A second idea I have instead of a keyway would be to turn some collars to fit on the insides of the wheels. Holes for set screws to the axle and then to the wheel could be drilled and tapped.

the wheels are just shy of a foot in diameter. The diameter of the axle is 1 3/8" and the hole in the wheel is about 3.5" deep.

Thanks for any ideas!

 

[Bob Korves]

The nominal keyseat size for a 1-3/8" shaft is 3/8". I don't know what your "tiny hobby mill" really is, but it may well not be enough to cut long key seats in steel. As for the wheels, their key seats would need to be broached with a 3/8" keyway broach using a hydraulic press or other means. You did not speak of what kind of motive power you have in mind, and how much total weight it will be pulling, on what types of grades, which might also change things. You will also need adequate brakes...

 

[SE18]

Thanks; I've got a 20-T press I'll use then and shop for a 3/8" broach. It will likely be diesel power. A friend of mine who builds locomotives for a living will be supplying some sketches for me. The grades are unknown as I plan to retire in a couple years near Harrisonburg VA where my daughter lives and build a RR. I already stockpiled 2,500 feet of rail. It will be primarily an agricultural railway hauling crops and timber (for fun of course too). There's a short stretch of track in backyard and tracks in 2 car garage for workshop.

 

[Tony Wells]

Ideally they would be splined to fit. Without a shaper it becomes more complicated, but you can do the job with a broach, as long as you are willing to machine an indexing slot in your broach bushing. You would not have to use as large a keyway, since the force would be distributed among the splines. And of course, milling the male splines on the shaft becomes trivial.
No larger than it is, a single keyway would transmit power sufficiently, but on power transmission components, splines are very common. I would consider this method superior in the event of any thin areas in the wheel hub, since as I said, the splines would be smaller (more shallow and not as wide) as a single drive key. It's more work, obviously, but an alternative that may have advantages.

Nice project. I have about 3 acres to play with.....maybe a retirement project. I am pretty sure I won't quit the shop when I do fully retire.

 

[Reeltor]

Thank you for sharing your wealth of knowledge. While I love RR's I would not consider building one; with that said the information on key-ways and splines will be squirreled away for future use.

 

[rgray]

I'm liking that tracked work table. Might be limited use around here for me in the winter, but then there are things that would be real handy to do outside in the winter also. Torch , plasma cutter and heavy grinding come to mind. Doing those in the snow would be piece of mind.
Very cool railroad!!

 

[T Bredehoft]

Splined shafts and hubs are alright, but unless SE18 is going to replace either the shafts or the wheels, it's pretty hard to put splines in both and have an interference, a number of keyways would do the job, but that's a LOT of keyways.

 

[chips&more]

If the size of the hole is the same as the shaft OD diameter, you cannot spline it, sorry, nada. One or the other would need to change size so the male and female spline would marriage. Keyway is about the only option. You are talking a lot of horsepower transmission. So a good robust fit would be in order…Dave

 

[SE18]

Thanks for your advice. If any of you are thinking of doing just a small shop railway, you can create track panels that are easy to move. They're steel ties. I use panels b/c I got a citation from our HOA telling me to remove the track in the driveway or else pay stiff fines etc etc (another reason I'm eventually moving). So I set the panels down when I need to push my workshop outside. I'm currently building a railcar dedicated to carrying a furnace for blacksmithing and it will also feature a crane. I'm also building a turntable that will go in the backyard soon.

BTW, each of the workshop cars has four trailer male mounts and 4 trailer jacks to act as outriggers, to keep the cars from moving on the rails when working and the trailer jacks can also be used to level the work area. I had one of these 2,000 lb cars derail and the trailer jacks were used to slide rails under to re-rail.

 

[easymike29]

Maybe this?


Gene