I bought this record 135 sash clamp which had a good coat of surface rust.
It was put in my electrolysis tank for a few hours which removed the rust.
It was then polished up with a scotch pad & WD40.
I repainted the blue bits as the electrolysis had loosened the paint in places.
Finally it got a coat of liberon lubricating wax to protect the bare metal.
Looks nice, seems a shame to use it!