JAX Iron, Steel, & Nickel Blackener - Metal Finishing Solution - Antique Finish Without Heat or Electricity - Pint

Q: does the product prevent corrosion after it is applied?

No it does not. Typically, you apply a wax and then buff excess away onto the product after the patina. The wax is what helps to prevent corrosion. It also depends on the environment the finish piece will be in. If it is outside or in a humid environment, it may develop corrosion over time.

Q: is this the same a gun blue? like hoppes or birchwood casey perma blue?

No. This tends to make the steel look more like old wrought iron or mill scale. At times there is even some slight greenish undertones. This also tends to be a little blotchy and not as consistent of a coloring as the bluing solutions.

Q: What is a good sealer to use after this ?

I am not sure what you mean by sealer but after I have used JAX solution I wash the stain glass and then use "Mother California Gold original formula Carnauba cleaner wax". This does a good job to protect the solder joints. After that you can us a cloth with a little "Lemon Oil" on it to go over the joints if needed several months later.