Starting work on one of those grungy LEO trade-in 640-1s.
Upon disassembly, I discovered that the rubber(?) mainspring swivel is half disintegrated.
Of course, it's out of stock everywhere.
I could make a brass replacement on my lathe in a few minutes.
So question is: Is there any reason that this has to be rubber?
Brass seems more better to me.
thanks.
