Carrier Bearing PreLoad Tool

8EL

8EL

Senior Member
The repurposed carrier spider being described in Tom Endy's 2014 "Rear Axle Assembly Restoration", directs one to machine and thread a 3/8-16 NC hole on center of that part. The spider I have has been hardened to the extent that it could not be machined. I had to anneal it to be able to make the part to be used as the tool Tom describes. This extra work to make the tool is well spent however, as it is a excellent way to accurately set the proper bearing preload.
 
I realize this, most of us however have HSS drill bits to which this part is of comparative or slightly harder composition. But yet had you a carbide drill, you would also be needing a carbide tap to thread the part....Much simpler to anneal the part to allow machining with conventional tooling. Henry hardened it to prevent wear on the side gear journals, in it's new life as a tool to be used to set bearing preload, this consideration is no longer necessary.

Thanks
 
Over the years people have asked me how I managed to drill and tap the spider gear yoke. I told them I took it to a machine shop to have it done and had no knowledge of how they did it.

Tom Endy
 
if the axles and everything are installed a piece of clothesline can be fed in and used to temporarily jam the gears enough to use the axle to rotate the carrier, it can even be extracted through the fill/ drain plugs
 
Tom Endy's tool I would think would be preferred over a cloths line, his account of its production explains why his instructions do not include this production detail of It
is an excellent alternative. Anneal it and it can be machined in the home shop......

Tom, you might want to include this detail in your description of it's production....


Thank You
 
I seem to remember making the one I use out of a Model T spider gear yoke. It had an open center. I made a plug for the center and welded it in place. I drilled and tapped the center for a bolt. The yoke fit into the Model housing fine.

John
 
I drilled mine with a standard H.S. drill, albeit with a high quality drill, lotsa oil and low speed. I was surprised it cut as easily as it did. I put my tap in the chuck to get it started and turned it with the key until it was done to keep it square and paralel.
Terry
 
Interesting, I have the 115 piece set of Cleveland made in America M42 cobalt HSS drills, using Tap-Matic cutting fluid. The drill speed was immediately reduced to a much slower than normal rate upon encountering this difficulty. So I don't think your bit was any better than mine. Can't say what you had there, but mine were quite hard, done to prevent premature wear. Of the two spiders I had they mic up within .002" of one another after 90 plus years of service. Both were both equally hard.

As said after annealing machining was comparable too 1018. The loss of hardness could have been restored after machining, but would be unnecessary in this part's new role.....
 
I have a yoke set aside to make this tool. I have an acetylene torch. How do I anneal the yoke? Some details please.
 
I use my foundry furnace to bring the part up to about 1375 DegF (cherry red) and then shut it down. I then cover to flue with a fire brick and allow it to cool for several (12) hours (end of day, overnight) to room temperature.

Your Oxygen acetylene torch fire is about 6200 DegF so you have plenty of heating capacity. The trick to doing it this way is to apply the heat up to the annealing temperature evenly. I would suggest a "rose bud" tip to make this task easier to achieve. It is also very important to allow it to cool slowly. The old timers I knew would say about 100 DegF an hour. You are going to need something to provide a mass to hold heat like the furnace provides. If you allow it to cool sitting on the bench, it will cool much to rapidly. I suggest that you get yourself some firebrick and stack them in a box like fashion leaving the to open to apply the heat. When annealing temperature is reached put a couple of additional fire bricks over the top to enclose the part. Preheat the fire bricks in the wife's kitchen oven (when she is not looking) to as hot as it will allow, probably around 450 DegF to prevent chilling the part.

Good luck, this is a fairly straight forward process.....
 
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