My lathe (250MV) would need to be turned off & on several times to get it to start & sometimes , if I did not press stop after a false "on", it would suddenly start when I was adjusting something in the lathe, with painful results. This happened 3-4 times. I had to remember to press the stop button every time that I wanted to do anything. It did do the stop, slow, go that the OP mentioned.
A part of the electrics, not sure what it is called, clips on to a sort of rail at the back of the component. I traced the problem to a bad connection where the component was not making proper contact to the rail. In the end I placed a block of wood against the component & the cover( held with some double sided tape) & screwed the cover shut , such that it forces the component onto the rail. Since then I do not get the problem very often & have not had a sudden start when working on the lathe.
Edited By Sam Longley 1 on 06/08/2021 13:02:01
Edited By Sam Longley 1 on 06/08/2021 13:02:50