[BC] Pot metal disease - was Old Speaker

[Gary Peterson]

" Dang ! That's an old baby ! I'm surprised the casting isn't cracked up
from
pot-metal disease. I would guess the adjustment is to center the armature...
M "

If you have any antique stuff made of pot metal, protect it from exposure to
low temperatures.  The disease you refer to is due to the tin in the alloy
changing crystal structure at low temperatures.  If you protect the metal
from cold, it will retain it's original strength/appearance.

Gary, K?CX