Hello! I'm currently in the "thinking phase" of how to peen over the second half of a hinge pin I'm making out of 1/2" mystery stainless. It does not work well cold in my experience and while I have a mapp gas torch and a hand-built propane burner that is free of any forge, I'm having a hard time thinking of how to get the end of the pin hot enough to peen. 

Here are the restrictions for the mental acrobatics going into this for me:

• I'm working in a Vevor 2-burner propane forge
• The hinge is 4' x .25" x 2" on one side, and 19" x .25 x 2" on the other (big strap hinge)
• No power hammer or press
• No oxy-xxx torch

I may be doomed to just heat it as hot as I can, slam it in the hinge, and use whatever heat is left to attempt to peen the other side over. I'm just not sure I've got the speed / coordination to make it happen. Any thoughts on the process or wizened advice is much appreciated.  

Will it move at all cold before it work hardens?  If so, one approach might be to peen until it gets too stiff, heat the whole knuckle assembly in the forge to anneal, and repeat as needed. 

Another option would be to heat the whole knuckle, then quench everything but the head of the pin.  At least assuming it isn't heat treatable stainless. 

I think the first option could be doable, and it would let me keep from messing up the tight fit I've already got but accidentally bending it while it was hot. Might be a little time consuming, but I'll give it a shot. I'm a little worried about cracking around the edges of the peen working it cold, but I suppose I could file the cracks out if needs be.

Have you TRIED forging a coupon to see if it CAN be forged at all, let alone cold forged? Asking people online without knowing what you have is just a bunch of wild guesses, do you have enough to try till one works?

Some SS HATES being heated and as far as I know all SS work hardens kind of abruptly. Your best bet MIGHT be a proper set tool and a BIG hammer and pein it in as few blows as possible. Brass and most Bronze alloys need few HARD blows or it wants to crumble. If the SS you have contains copper it's probably on the copper alloy list of rapid abrupt work hardening alloys.

You COULD just buy a little forgeable SS rod and enjoy a better chance of success you know.

Frosty The Lucky.

 

another option would be to use a mild steel pin instead of stainless, afterall its worked well for millennia, it'll work well for this too!