I read Orrin's bit about using graphite electrodes for electrolytic derusting. I
saw some cheap on ebay and picked up some, maybe $10. The first ones arrived
smashed up, the second ones showed up intact. They're about 8" long, maybe
1/2x1" rectangular bar (very roughly). They look fragile. As I said, they were
over $5 apiece. They will probably work fine, although I often need an electrode
that is longer than that.

Today I was rooting around industrial South Seattle looking for a used but
usable welding ground clamp and I noticed these long perfectly round things that
looked just like graphite. I picked one up -- it's 12" long, 3/8" diameter,
looks pretty strong, looks real conductive. It's a scarfing electrode, first
unclad one I've seen, and it must be made of some sintered carbon. They had
hundreds and hundreds available for 35¢ each. Skeptical, I bought one. I just
hauled out my DVM and my pointy-sharp leads and probed in in ohmmeter mode. End
to end it's 2 ohms or less (my meter isn't accurate in that range) and it
appears to be just as conductive on the sides as on the ends. In short, it
appears to be a real good candidate for use as an electrolytic derusting electrode!

I'll test it and report. This would be great if it works like I hope it does, it
would mean electrodes that don't rust, no cruddy solution, without the huge
expense and fragility of graphite.

GWE