I use a lot of glass chambers as it's very easy for my local glassblower to add AceThred feedthrough fittings whereever I want them, you can see the inside, in small sizes (up to 4" od)they are fairly cheap, and you get an insulator and chamber all-in-one.
Glass is equivalent to stainless down to about 10-9 Torr where you start to see more hydrogen permeation through glass.
I only wear safety glasses around the small chambers. For my big glass chamber (9" dia) I made a shield from 3 rectangular pieces of lexan which I joined at the two long corners with that stick on plastic L stuff that is used to protect outside wall corners. Got them at a paint and wallpaper store.
Steve
Created on Friday, March 16, 2001 7:08 PM EDT by Steve Hansen