"NSM" writes:

"geoff smith" wrote in message
. uk...

I am seeking advice on the replacement of the moving contact on a 2 amp
Variac.The original "Brush" appears to be made from Graphite and is about
4mm in diameter.
The makers were Zenith Electric London (RIP).

Sometimes these were a critical design, to prevent shorting adjacent turns,
but it looks like yours isn't. Just find the nearest brush you can which is
bigger and plane it down. Use a coarse file, not any sort of sandpaper or
emery paper.

There's no way to avoid shorting adjacent turns. Else, there would be
gaps in the output voltage! However, the width could be important
to avoid shorting more than one adjacent turn.

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