Another Jeep J20 Build

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I did not have the correct .005” shim so I modified a different diameter shim to the correct size.

Here I have clamped a much thicker shim of the correct diameter to a larger shim of the correct thickness. Using the larger shim as a guide I trimmed the edge of the .005” shim to size with a die grinder and stone. This worked well.

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The new pinion nut is too long. The deformed end that provides extra friction to prevent loosening will not reach the threads of the pinion gear. I placed the nut in the lathe to reduce the length but I could not get the thrust surface of the nut to run true. It had approximately.030” of runout. With the combination of high tension and torque on this area of the pinion I must make sure the nut contacts evenly on the yoke.

Here I have applied layout ink to the surface and will check it.

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Picture for previous post.

[digr]

Do you have another pinion that you could run between centers with the nut threaded on and then face the nut

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Originally Posted by digr

Do you have another pinion that you could run between centers with the nut threaded on and then face the nut

Yes, I have another pinion but I had not thought to do this. My plan was to make a threaded mandrel. I’m not sure if I have a dog big enough. If I don’t I guess I have a decision to make, either make a new mandrel or lathe dog.

[threepiece]

I used a different method for setting up the carrier bearings. I made a gauge from a 1” diameter steel bar that is 8.630” long. This dimension is about .040” less than the distance between the carrier bearing races. With feeler gauges inserted between the gauge and housing I can measure the width.

Fitting a .040” feeler tells me the distance is 8.070”.

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With a height gauge, ground flat bar a weight and a flat surface I can determine the distance between the carrier bearings.

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Remember the loosely fitted bearing from an earlier post? Here I have made a series of center punch marks on the surface to improve the fit.

[toprecycler]

Originally Posted by threepiece

Here is the new rear crossmember. At 1/4” thick the wall is twice as thick as original. It was made from a 4.5” square tube ripped in half. There was a small amount of stress relief that caused a slight inward bow.

Just a thought about the inward bow. Might not actually been stress relief. My thoughts it might have been caused by the heat generated in cutting it apart. How did you cut it? If by torch, plasma, or laser, I believe it would be because of the shrinkages by metal naturally.

I remember several years ago at old job, we had a frame to make and used something like 8x6 tube cut in half so we had 4x3 channels. We requested our supplier to laser cut it so it would not warp.

When it came in, it had a 3/4” bow in the center of a 8’ long piece. I used a torch and heated up spots on the back side and heat straightened it flat again. It was fun to watch it bow more as heat was applied, and then shrink back straight as it cooled.



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[threepiece]

Originally Posted by toprecycler

Just a thought about the inward bow. Might not actually been stress relief. My thoughts it might have been caused by the heat generated in cutting it apart. How did you cut it? If by torch, plasma, or laser, I believe it would be because of the shrinkages by metal naturally.
Sent from my iPhone using ShopFloorTalk

This was cut with a saw, so no considerable heat involved. I thought about straightening it but decided not to. When the trailer hitch is fastened to it the bow will largely be removed. The crossmember will then be preloaded in a desirable direction and the additional tension will, I hope, aid in preventing the fasteners from loosening.