When adding lye, do not just dump it in, but scatter it over slowly over the whole length of the tank. What
happens is that if you dump it all in one spot, it will cause it to boil over the tank. From 15 to 40 minutes
in the bath is required, depending upon the amount of parts that are being processed.
The most unpleasant part of using this formula is that in mixing in the ammonium nitrate, a large amount
of ammonia is given off, so have good ventilation in the finishing room. When adding more ammonia
nitrate to a hot tank, take a good breath, pour it in and get out of the room. The ammonia fumes will put
you down if you are not careful. Vent out the room and you can start bluing.
Lye is no problem to handle. In this formula, is not to aid in coloring the metal but to raise the boiling
point of the solution and thereby prevent excessive loss by boiling away of the other ingredients. In this
mixture the ammonium nitrate stays in the tank, ad only water and a little lye are lost through boiling,
The black produced by this ammonium-nitrate-lye process is very durable, and I have some guns that
have been in use for close to 20 years.
To use this solution, the metal parts are degreased either by Oakite solution and placed in the tank.
After blacking, they are rinsed in water, either cold or warm, and dried and oiled in the regular manner.
All of the blacking processes that use lye attack lead and destroy soft solders, and can not be left in the
solution for over 15 minutes, so remember this when bluing rifle barrels with sweated on ramp front
sights.
The processes does not attack aluminum alloys, they devour them! Under no circumstances place a
part made of aluminum in a steel blacking solution. It will be dissolved quickly. Silver, copper and brass
are not affected at all by the blacking solution.