LeFusil, Is the heat blue durable? Enough for a trigger guard? I have one to blue. Interested as the heat blue method doesn't appear to take a lot of special ingredients!
Thanks!
It doesn't take a lot of special ingredients, but it takes a great deal of caution. Molten potassium nitrate at over 700 degrees can cause some very severe burns. Leather gloves, safety glasses, and a full face shield are good precautions. Heating a pot of previously melted salts can erupt violently as the bottom melts and the top is crusted solidly over. For this reason, put a bolt or lag screw in your pot before it cools, and unscrew it to provide a pressure relief hole when re-melting. Heat blue is not as durable as hot salts bluing or rust blue, but it is fairly durable, and a good method for screws and other small parts that won't have their temper changed adversely.
