Don't bother... Weller stuff is junk... that's why you're trying to
repair the the one you have... lol
Do yourself a favor and try one of
these...http://www.hexaconelectric.com/thermo.html
They ain't cheap... but man do they last.

Weller makes junk better than your junk by maybe 40-50 dB.
Thanks for your unsolicited opinion.
W4ZCB

Harold, I have no affiliation with Hexacon... or do I sell their
equipment. However, we do use their equipment... and it has proven to
be much more reliable than Weller stuff. I guess you get what you pay
for. Not surprising I guess.

I was commenting on your speech compressor not the equipment you use to
build it.

If you had read the other posts, some denegrating the Weller company, you
would have read a comment of mine that explains my use of Weller products
for over 60 years. That includes personal use of several models of their
irons as well as the industrial use of Weller irons and guns by my employees
in a manufacturing environment. I HAVE used a few other irons, a favorite
being the Antex for SMD work. I suspect that, unless you're morbidly obese,
I have likely melted more solder pounds than you weigh and am particularly
offended, by people offering their unsolicited opinions on subjects they
know little about. Go build a compressor. Most of us these days, do it in
software with DSP.

W4ZCB