Copper sulfate as marking out dye

[Inflight]

Hey Marv,

Thanks for the tip. I'm happy to report that the copper sulfate solution works well. I dissolved some copper sulfate into water and added a few drops of sulfuric acid. After cleaning the HSS toolbit with lacquer thinner, fine steel wool and isopropyl alcohol, I dipped the tool into the solution followed by a rinse in water. The copper plating scribes very well and holds up to the heat of grinding.