Update - the Variac Went Up in Smoke!

they're not too hard to rewind, I wouldn't bin it

NT

Yes how old was the Servisol? I trashed a headphone socket using the older stuff, the glue holding the contacts melted. Brian

Really? How do you get the contact area? Brian

Old windings are shellac insulated and that dissolves in ethyl alcohol. And almost anything else. It is apparently used to coat pills so they dissolve in the intestine and not the stomach.

So with shellac, the question is 'what will *not* dissolve it?'

mechanically remove the shellac where the wiper needs to touch it, sander maybe?

Several different Servisols. The contact cleaner seems to be hydrocarbons but they also do an IPA one (which will dissolve lacquer, I think).

sandpaper, scraper, solvent, whatever. Not a problem.

The one now awaiting recycling was manufactured in the 1940s and insulated with whatever they used back then. As you say, shellac I guess back in those days.

That could well explain it then!

There are probably people that would buy it as is. Variacs are hard to get now.

NT

It would only be worth a fiver in the state it's in now - if that. Not worf the bovver.

Can't comment on the current market, but back in the 70's I worked in a large and well-equipped industrial research lab. We were always in trouble at the end of the FY if we hadn't spent our generous budgets. Rumour has it that some people would go to stores and sign out some large variacs, which got charged to the budget. In the new FY, you could take them back and the funds would magically be switched across the year boundary. (I've heard of other labs where the same trick was done with gold or platinum wire and mesh).

The 3 faulty variacs for parts only on ebay now are priced at £60, £225 and £53.38, all plus postage.

NT