Oops!

Our electronics guy at work kindly had a look at my 1951 sewing machine foot controller - the one I took apart last week and scraped away what I thought was white powder of corrosion. Apparently it was asbestos! Oh well too late now. Have cleaned the area I was working in very well. Remind me never to try and fix old electronics when I clearly don't know what I'm doing again.

After all that the controller is fine. Letting the expert have a look at the motor next. (Whole sewing machine - cast iron too heavy to carry to work)