How To machine one piece axle box

This forum is dedicated to the Live Steam Hobbyist Community.

Moderators: cbrew, Harold_V

RET
Posts: 960
Joined: Wed Jun 07, 2006 8:36 am
Location: Toronto, Canada

Re: How To machine one piece axel box

Post by RET »

Hi,

Two things. First, as has been said, if you plan on selling the castings, it is likely better to keep them as is. Only start the machining process if you plan on going to completion with all the castings and you have both the skill and the equipment to do an accurate job.

Second, in the machining process, make sure you run all the castings through each step at the same time, don't do one to completion and then try to get the same setup at each stage for the others.

As I've said before, when I make something, I always plan the complete process in my head beforehand and I'll usually go through two or often three versions before I settle on the one I'm actually going to use. This thought process is essential to winding up with a good part. In many cases, I have to draw the part in CAD (two and in some cases 3D) to finalize the process.

Hope this helps.

Richard Trounce.
flavinny
Posts: 32
Joined: Sun Jun 29, 2014 2:47 pm

Re: How To machine one piece axel box

Post by flavinny »

I don't have the drawings yet but the procedure hoppercar described above is what I was considering except I was going to chuck the slug. Mounting it on the faceplate is probably a better idea and more secure. I did my drivers this way by using a chuck arbor in the spindle and turning the Jacobs end to fit the driver I was then able to clamp it to the faceplate and turn remaining surfaces,
Can a thread be turned on the slug so that the axel box can be tightened up square to the slug and is this strong enough to support the remaining work to be done?
User avatar
Bill Shields
Posts: 10464
Joined: Fri Dec 21, 2007 4:57 am
Location: 39.367, -75.765
Contact:

Re: How To machine one piece axel box

Post by Bill Shields »

flavinny wrote: Wed Dec 28, 2022 3:15 pm Can a thread be turned on the slug so that the axel box can be tightened up square to the slug and is this strong enough to support the remaining work to be done?
I would not use a thread to hold / locate anything without some sort of incorporated pilot and / or clamping setup.
Too many things going on to bother listing them.
hoppercar
Posts: 616
Joined: Sun Jul 22, 2018 4:09 pm

Re: How To machine one piece axel box

Post by hoppercar »

You don't need the thread on the aluminum slug.....just turn it to a close slip fit to the bearing bore,.....and use step blocks and clamps on the lateral spring bosses to clamp it to the faceplate. ...then all you have to do is bore and thread the second side.....it will be concentric......by the way. It's best to have your bearing cone adjustment nuts allready made, so you can use them to check the threads in the lateral boxes as you are chasing them....
tetramachine
Posts: 236
Joined: Sun Mar 19, 2006 6:27 pm
Location: NJ
Contact:

Re: How To machine one piece axel box

Post by tetramachine »

Clamp it in a mill, bore one end. Then use an EXPANDING collet into that bore. They are made soft to be turned to the size needed. I made a collet tube just for these collets, that used a 3/4 threaded rod, fixed to the tube. A lot more force than a handwheel.

You could also use a hex collet holder, and a 3 jaw chuck, or square and a 4 jaw.
My wheels don't slow me down
765nkp
Posts: 777
Joined: Sun May 06, 2007 9:24 pm
Location: st louis, mo

Re: How To machine one piece axel box

Post by 765nkp »

I wouldn't use those. Fabricate individual journal boxes out of steel or cast iron and use ball bearings.
Much easier, I believe Mike Venezia made this change when he redid the engine.
Tim
Attachments
IMG_20230101_121435_823.jpg
flavinny
Posts: 32
Joined: Sun Jun 29, 2014 2:47 pm

Re: How To machine one piece axle box

Post by flavinny »

I just got the drawings and have a few questions. I will probably start with Bearing Adjusting nut by boring and threading a piece of stock long enough to make eight rings. I can then part them off and use them as a gauge when doing the internal threads. My question is what to use for material? A 3" piece of CRS and boring a 2.375" deep does not sound like fun. A piece of
cored bearing material is ~200 dollars. I do have 3" brass can that be used.?
My next question is related to the bearings. Apparently, the size is commonly used in car wheel bearings. There a wide swing is prices $40 to $150. I did not see any grades marked on the ones I looked at but what would be sufficient. I suspect something from the local auto parts would work. I want to have them on hand before starting.
Next, I do not see any seals being used. As long as these have been around, I guess this is not a problem.?
RThomp
Posts: 140
Joined: Tue Jan 17, 2023 5:11 pm

Re: How To machine one piece axle box

Post by RThomp »

I'd absolutely follow 765's advice and just make them individually. I think LE actually produces bronze castings for the boxes on most of their engines, so maybe bronze would be a good material choice as well.
flavinny
Posts: 32
Joined: Sun Jun 29, 2014 2:47 pm

Re: How To machine one piece axle box

Post by flavinny »

I know about the new design and agree they would be easier and maybe better. What I like about this hobby is the challenge in figuring out the "how to". I am not a machinist so success in building an engine and solving the construction problems is satisfying and rewarding.
User avatar
Bill Shields
Posts: 10464
Joined: Fri Dec 21, 2007 4:57 am
Location: 39.367, -75.765
Contact:

Re: How To machine one piece axle box

Post by Bill Shields »

i did mine last set of boxes by starting out with a piece of square bar stock (keystock) and bolted on a face with the 'ears' that also holds the bearing in place.

not prototypical, but ......
Too many things going on to bother listing them.
Pontiacguy1
Posts: 1566
Joined: Thu Apr 26, 2012 10:15 am
Location: Tennessee, USA

Re: How To machine one piece axle box

Post by Pontiacguy1 »

Any of the tapered roller bearing sets will work. Timken (the inventor of said tapered rollers) are going to be your most expensive, but INA/FAG, SKF, Koyo or Peer will all serve just fine. You are nowhere near the design capacity or speed rating for any of them. Make sure to get the cup and the cone (cup=outer race, Cone=inner race) from the same manufacturer if they don't come as a set. Theoretically they would be the same, but there may be slight differences in the taper angle.

I'm not sure what they originally used to try to seal these, but I would want some type of shield at least to keep the dirt out.
User avatar
Dick_Morris
Posts: 2842
Joined: Sat Jan 04, 2003 2:09 pm
Location: Anchorage, AK

Re: How To machine one piece axle box

Post by Dick_Morris »

A 3" piece of CRS and boring a 2.375" deep does not sound like fun.
It sounds like these parts have a through hole. If so, you might check the online metal suppliers to see if DOM tubing is available in the correct size. A number of the replacement bushings in the suspension and brake gear for Alaska Railroad #557 started as pieces of DOM tubing. For our use the bushings were then sent off to a heat treater after machining to be case hardened.
Post Reply