removing clear varnish from a old blade

[Sajen]

Originally Posted by milandro

I was wondering what is the general advice on removing varnish (why do people do this? ) from an old blade

Is there a product ( and how to apply) which would be safe enough as to protect patina and do not damage the blade (and visible layers)

Hello Milandro,

It depends on the used varnish. You can try benzine (for lighters) which works well with shellac for example, acetone works by other varnish, by others turpentine. With all three liquids you can't harm the blade. By wood or other natural materials you have to try it carefully on a not visible place.
I have done it many times, don't be afraid to harm the blade.
What you do mean by patina? Dirt and rust is not patina. But some blades get over time a black surface, strictly speaking also rust, don't be removed by a cleaning like this, it will become a little bit more shiny maybe because you have washed away dirt and loose rust but it will stay black, I guess that you mean this by patina.
Attached a close-up from a blade with such a black surface and was cleaned once from a varnish.

Regards,
Detlef