How to make a small roll pin?

[wshelley]

So I need 20 small beryllium copper roll pins, .125" diameter, 1.25" long, .028 thick wall. No luck finding a source, apparently beryllium copper is out of favor but it is spec'd and no substitutions are allowed. It seems that it would be too small to make with a roller so I'm thinking of milling a groove and pressing the material into the groove, flipping it over and hopefully being able to press it around a pin into the groove and finish the diameter. Will it work? Any thoughts on a better solution?

Ward

[Mcgyver]

i'd stay away from the BC as well, especially machining, but your challenge reminded me of a description G Lautard in one of his books gives on making small hinges - the round part of which is a similar shape to a roll pin.

basically, ream a hole the desired OD in a piece of steel. with a slitting saw the thickness of the material to be used, mill a slit in the steel tangential to the hole. press the material in in the slot and it bends around forming a loop. for a pin, I'f put a steel follower in and after forming as such you'll probably have to press the whole thing throw a hole to form up the remain edge

I've not done this, but would think it holds promise for this tricky little part

[SGW]

How springy is the stuff? Is it bendable, and will it stay bent? And if it is and will, how do you develop enough spring in it after forming to make it a workable roll pin?

[Optics Curmudgeon]

Have you tried BeCu Industries in Scotch Plains NJ?

Joe

[agrip]

Call US Fastener Lake Forrest California
949.770.7711

Their lit admits Beryllium Copper spring pins exist, and work at higher temps than carbon steel. BeCu alloy spring pins are age hardening.
The alloy # escapes me but the numerals 172 are in there I just dont remember where the zeros are.

Hth Ag