What Lacquers have been used on cables with succes

Sometimes enamel is also used. I think the key is to have as thin of a coat as possible to avoid corrosion of the wire's surface. This makes a very small amount of material to have any kind of dielectric absorption, and thus comes closer to the air dielectric. Using an over size tubing to protect it, and provide air all around the lacquer coated wire, and still protect it, is the way I went. Also, try not to bend or kink the wire when making the cable, because this might fracture the lacquer coating and allow a place for corrosion to start, and it also may corrupt the grain structure that was drawn into the wire during manufacture. These are some things that I used when doing my DIY cables.

I used magnet wire that is already coated with something, and I only bare the ends for terminations. The oversize tubing is only for protection.

When I clean it, I use 0000 fine steel wool on the wire ends.