Yesterday I was at the lab (which is absolutely freezing, the boiler is broken). I installed the electron gun:
I fumbled the flange when I was removing it, and broke the ceramic tube. Ugg. I’ll have to make another one.
Notice the ceramic’s discoloration from the plasma of the Fusor. Why? Plasma is corrosive, but still rather surprising to see such a dramatic change.
Unfortunately, I installed this incorrectly: a centimeter of the lead wire is unprotected by ceramic. The plasma was forming around this lead.
So I’ll have to open the chamber back up and try again. I think it’s time to invest in a powered torque wrench. Doing the large conflats by hand is a real time consuming pain in the ass (and knuckles when the wrench slips).
Another useful upgrade are these plate nuts: