Has anyone ever tried making their own wrist pins? I have been working on my latest project which is a Citrus 22. As I was cleaning the parts for inspection I found a bad piston. I obtained a good one but it was too big as it was .040 over sized and my jugs are .020 over sized. So I chucked it up and machined the piston down. Looks great. Until I went to go put it on the rod. The wrist pin bore in the piston is worn a bit and the good original wrist pin is sloppy in the bore. I have considered starting over with a different piston but I have so much time in the current piston and I like a good challenge. So my question is this. What material should I use to make a good oversized wrist pin? Should I case harden it? Any help or ideas would be appreciated.

I made some for a 28 one time. I bought some Streesproof or similar metal and turned and ground it oversize to match my oversize piston bore and rods then I honed out. As far as A TEN I found some TRW pins close in size,then I ground to length and honed the piston and rod bushing to fit new pin.

I have tried to find an existing pin that is close and have had no luck. The original pin measures 1.2187" The pin bore in the piston is measuring 1.2283" and is out of round by less that .0005" if I could find a pin or make one that is around 1.2265" or 1.227" I would be set. I am just concerned about the material used and whether it should be case hardened.

WyoCat - Wouldn't it be easier/cheaper to make a thin-wall bronze bushing for the piston, and machine the piston out to take it?
Yes, the wrist pin has to be case hardened .. it has to be deep carburised, to a pretty hard level, around 55-60Rc .. and it then has to be ground, to some very close finished tolerances.
All of this seems to add up to a lot more work and cost than making a thin-wall bronze bushing and machining the bore in the piston?
Of course, the $64 question is whether the piston has adequate thickness in the pin bore to be able to be machined out and support a thin-wall bushing.

Hey Chad, I have made several piston pin's for my crawler's. I use 8620 steel leave .010 to .015 for grinding on the O.D. I case hardened 55rc .050 deep so when you end up grinding the O.D. you are left with about .035 of case harden. I have checked the hardness of original piston pin's and they are about the same. If you don't have an O.D. grinder take them to a tool sharpening place and they should have an arbor they can put the piston pin on and grind it between center's. It cost me about 25.00. Here is a pic of one I made. Mike

OzDozer, I have thought about doing the exact same thing with the thin bushings, but the bore strut for the pin on the inside of the piston is only about a .179 wall thickness. I really hate to take away from its stregnth.

Miked238, That does not sound too bad. I think I should find someone who could finish grind this for me before I do the rest and end up with something that is useless.

Now, my other thought is this. It is just a 22 piston. I should be able to find another good piston fairly easy with a good pin bore, even if I have to turn the piston OD down like this one. I just like a good challenge and like to figure things out and see it work successfully.