William Noble wrote:
I posted a while back about this P&W comparator I had picked up - a
mechanical device with plus and minus 3 thousandths full scale, and someone
said that the usual failure is the copper spring (a strip of spring copper)
that connects to the pointer - well, they were right, it's broken - is there
an inexpensive source for a replacement? make one? or just use thin
stailess fishing leader?


How tough to get in an out of the unit?

Seems a low cost-risk to try the stainless leader material.

Got a model airplane shop around? They stock music wire in small
sizes, and most, these days, stock a variety of carbon fiber rods and
strips.

A guy could probably scrounge around and find a few strips of Be-Cu
shim that could be used for springs.

Cut with sharp scissors, and don't lick your fingers after. No
polishing, just a really cursory deburr with some sand paper.

Cheers
Trevor Jones