I have posted extensively on this back in 1998 on the old list. Reversal will not clean the stuff off.
With fusor I and II, I used an SS inner and outer grids and found I could readily clean all components with half strength muriatic acid (Hydrochloric) when the bell jar or dessicator became so stained as to affect the viewing. This also cleaned the alumina insulators.
Make sure to bicarb solution the items after this effort, (neutralization), followed by a thorough distilled water rinse and alcohol wipe down.)
Once I went to pure tantalum, the stains are permenant and fast to the system. This metal and its oxides are proof against most anything! The normal solvents for the tantalum residue are hydroflouric acid (nice in glass bell jars) or molten alkali (like the idea of handling molten lye?)
Now in fusor III only the view port demands cleaning and only abrasives (coarser polishing compounds - cerium oxides) can mechanically abrade the stuff off the glass (it is hard as hell).
So, if you can stand it, stay with SS grids and you need only rubber gloves and muriatic acid found at any hardware store and a box of arm and hammer bicarb for a quick and complete clean up.
Richard Hull
Created on Wednesday, June 06, 2001 10:57 AM EDT by Richard Hull