I have to admit that I've learned a bunch I never knew before. Of course , the thing is that I was not paying attention during my younger days. A nyway, I finally figured out how to disconnect and correctly reconnect th e master link on this "roller" chain. (At least, it's inch-pitch. It fo llows your description here;
"Diamond roller chains had the master male half of the link with the rivets that came through the link and protruded out the other side maybe 3/32".Th ese two pegs not rivets had a cutout around the peg and the clip on plate w as drilled so that the holes fit into the slot with the proper dimension.To install, one bends the chain so that the pegs get closer and the plate f alls over and locks into the slot.The beveled edge is up or out, the shar p edge goes down or in as it were, and that sharp edge lets the plate pop off easier when the two pegs are "squeezed/ compressed closer.The older Di amond chains had a "hear it snap" stamped into the locking plate."
I remember seeing those older Diamond chains, but I had never used one.
As for use, at present the connected unit of cog, chain and chain ring are adorning as sculptures. I feel fortunate to be here, but I think see ing it hanging there will force me to give it company and put it on the roa d.
Happy 4th
Steve James
Bronx, New York, USA