We use a micro-sandblaster to clean the ceramics. It is not worth
trying to save the filament wire itself when they start to deteriorate.
A role of rehnium filament wire is cheap and with a small spotwelder
our home made filaments (we've been doing this for 20 years) last as
long or longer than the commercial ones.
Prof. Jack m. Miller
Dept. of Chemistry,
Brock University,
St. Catharines, Ont. L2S 3A1
jmi...@spartan.ac.brocku.ca