Are banjo bolts grade 8?

A more common problem than many realize. Dead soft copper is a pain in the butt to stamp, and burrs easily. Harder copper will stamp nicely, but it does not deform to seal properly.

So, when someone goes to China for washers, they ask for cheap. Half the time the purchasing agent does not have a clue about what that washer actually does... So you get half hard copper, stamped & flattened. The cold working of the manufacturing process cold works it to nearly full hard. Much lower manufacturing cost, but the part is not to spec.

This is easy to fix. Copper anneals readily over 750f. Lay the washers down on a firebrick, and grab the propane torch. Heat them until they get to red hot, then walk away and let them cool. Dead soft now. They will have a thin film of black oxide, which you can wipe off with steel wool.

Take an old pair of washers from a used caliper. Anneal one. Now try to bend each one with your fingers.

Wow, what an interesting post. Thanks:cheers:
I was concerned about trying to file or smooth out either the caliper or the line. How would you do that without the risk of metal filings getting in the system?
C