|
Caustic baths, like Oxynate #7, contain both sodium and potassium nitrate, and have to come to a boil at around 280+ degrees (290 for Nickel Steel), which is controlled by either adding salts or water. If you're going to blue frames on single shot shotguns, etc, then there is a cyano additive to keep them from turning a red or purple hue. Also, every caustic salt manufacturer has their own recipe, and they tell you to do things differently. This will not work on stainless, and takes another type of salts. Also, don't add the cyano additive until you have ran the bluing bath three times, with guns, as it can kill it.
What I have found, is that hot water rinses, with #7, are mainly unnecessary, if you use compressed air to get any remaining salts out of threads on barreled actions, etc. Plus, if a little white powder was to leach out and appear, then tell the customer to take a toothpick and remove it, then put a little oil on it. I've never seen that hurt one, and it rarely ever happens.
You can get by with four tanks, two heated, and two with cold water to rinse in. The first heated one holds cleaner, like Dicro-Clean 909, which is boiled. Next, a cold water rinse, and then into the bluing bath for 30 minutes. After the bluing, a thorough rinse in the second cold water bath. After, use some compressed air on any threaded assemblies, another rinse, and then a dip in water displacement oil.
You either need to blue the parts right after their polished, or spray them down with Brownell's Hold, and do them a day or two later, when you have a batch ready. No more than two days is what I do.
I suggest buying a rubber apron, face shield, and rubber gauntlet gloves to protect you from splashes. I burnt two fingers on hot bluing salts years ago, and still carry the scars.
|