De-crimp fuel pump rivet

[edgewood bronco]

I finally found some viton material to make diaphragms for my dual- diaphragm pump on the Bronco with vacuum wipers.

My issue is, how do I decrimp the 'rivet' that holds the assembly together? I'm working on the vacuum side of the pump now, the assembly I'm talking about is this: there's a rod with a hole in one end to engage the arm that rides on the cam. The other end goes through two steel discs that sandwich the diaphragm. It looks like it was put together with a press. Does anybody have any recommendations on how to get it apart in such a manner that I can re-use it?
I was thinking of grinding off the head and carefully drilling and tapping a hole in the center of the rod so that I can install a machine screw with some locktite. I'm just not sure if I can drill a hole that's perfectly centered and in line with the rod.

Or what about making a whole new rod out of allthread? If I were to this route, I'd be worried about wear where the loop contacts the arm. The original rod is copper plated, and I'm wondering if it's coated to somehow reduce wear.
Thanks for your input.

 

[rbohm]

i would make a new rod, but i wouldnt use all thread, too many stress risers. as for the material of the rod itself, as i recall it was just mild steel. if you are worried about wear, then make the rod out of grade eight or aircraft grade steel as they are designed for high wear situations.

 

[edgewood bronco]

Thanks. I'll let yous know how it turns out.