Googled peening u-joint pin without much picture results.
So here's what I did.
Please post better options, opinions, mistakes you see or better ways to peen pin for future Googlers.

Thank you for all the help on MTFCA.
Couldn't have done it without your info.

Used a bolt, in the joint housing plug hole, to support pin.
1/2-20 bolt should be the proper thread. A spindle bolt will screw in.
Screw bolt up to the pin checking pin is even on both sides.


Supported the other side with scrap wood screwed together and screwed a board on top to lock and steady the driveshaft tube so it doesn't move when peening pin.

Pin is soft but took 20-30 hard hits, with flat punch, to peen tight.
Rotate driveshaft and screw bolt tight against the peened side and peen the other side.

Well done, you are now an expert!

Cool Anvil!!!

Looks good to me...I would next take a pointed punch and hit it again 6-8 times to make an inner circle and swell the metal a little more in a concentrated circle. The pointed punch will move more metal on the edge and make it a little more tight. Might not be necessary but the dimples will move more metal to the edge than a blunt punch on top.

Tim Moore

These pins are wonderfully soft and peen over so pretty! I used a 1/2-20 bolt too and a flat nosed alignment punch on mine.
We're not supposed to use an alignment punch to hammer on things I guess. Some of us do anyway. :-)

Not to argue, I worry about a peened over "cap" being thin and flaking/popping off the original pin material.

Different scenario but alike if I may:
The young guys I work with (we drive hardened/ground "drill style" bushings into place on everything we put out the door) pound the heads of regular bolts and special shear bolts (our drivers) until the top is so thin, when a section breaks off it'll bite you in the leg/fall apart and leave what holding on?
Not much.
I throw bolts away when the heads look too thin and grind the corners off bolts with some meat left to do more driving when they aren't looking. ;-)
:-)
I popped my pin down until snug and stopped.
Sorry for the babble.

When NORS parts were available, there was pin that had a head on it. It would be a nice item for someone to reproduce to make the job easier.

Jason,

Good that you supported the 1/2-20 bolt with the anvil. Otherwise, you run the risk of stripping out the 1/2-20 threads in the housing. You obviously knew that. I just mention it for any who decide not to back up the bolt with something solid.

I peen one end of the new pin first on the vise anvil then use a fan arm bolt with a relief drilled into the end and inserted into the torque tube to peen the opposite end - same effect.

I'm with Larry. A round head rivet would be ideal. Could probably find them at McMaster Carr. But probably have to buy a box to get one. Any well stocked hardware store would have them.....for those of you that still have well stocked hardware stores. Quickly becoming a thing of the past.

When you peen each end you ensure that each end of the rivet is tight in the u-joint collar and can't work around. A headed rivet will only be tight and completely fill the hole at one end. There will be clearance in the other end that will allow the rivet to move around and maybe work the peened end loose.

I took an entirely different approach suggested by a friend. Line up the universal on the shaft and tap 1/4-20 right through. It takes a good tap, not something you find in your Craftsman 72-piece set, because the shaft is pretty hard. You really wouldn't want to break a tap in there! Then you can run a 3/4 long set screw in from both sides. A tiny bit of grinding on the end of one screw before you put them in makes sure they end up flush. Installed with red Loctite - they're not going anywhere.

Friend has been running his car with this arrangement for 15 years. It's also easier to take apart if you ever need to.

Chris,

Probably not a likely thing, but what do you do when you need to replace the U-Joint? The threads won't sync up anymore.

Jerry,

You are right, both that it would be an issue and that it is unlikely. I think I'd have two choices -

- Go back to using a pin
- Retap it and not worry about the mess that might ensue inside the shaft. As long as the set screws are well threaded in the U-joint collar and tight against each other, I think it will be fine.

Yes, I know this isn't the "right" way to do it, but it worked for me!