Copper sulfate as marking out dye

[mklotz]

Dykem is not very satisfactory for marking lines on a lathe tool bit while grinding to shape. The rough and tumble action of grinding and cooling easily removes the marking fluid and the lines. If you can get your hands on a solution of copper sulfate, dip the tool in that. A light coat of copper will deposit on the tool and it shows scribed lines well. The electrochemical bond is stronger than that of marking out dye and your marks will survive longer.

Copper sulfate crystals and solution are available on the web from Amazon and other suppliers.

[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.