Parkering: Manganese or Zinc?

[Gonzo 0]

What type of parkerizing is closest to the original parkerizing? Manganese(Dark) or Zinc(Light Grey)?? Or what type of parkerizing does Joseph Scott offer? Please let me know.

[Joseph Scott 0]

I use the manganese phosphate. Zinc phosphate has almost no color while the manganese is a light to dark gray. To get a darker gray-black, you must coat the surface with an black oil or grease which seals the surface and gives the final color. I have a home brew solution which comes very close to the "Blackened" original. If you want the green tint everyone thinks is great, spray surface with OD camo paint and wipe it off while wet. Just enough stays in the pores to give a greenish tint. Color of phosphated (Parkerized) metal varies with hardness, time in bath, surface preparation and concentration of solution. I have gotten several different shades out of bath under the exact same conditions and the same time.

[Brian Alpert 0]

Joseph, Didn,t you give an original JSAR part to a metallurgist for analysis some years ago only to find thet the surface was blued rather than Parkerized? You have pointed out that the original specifications call for "blackening". I personally have been amazed at the variety of colors of "original finish" JSARs....from black to light green. Time does amazing things to finishes, assuming they all began the same color...which they probably did not.

[Gonzo 0]

Thanks Mr Scott! I really appreciate it!!

[Joseph Scott 0]

Brian, I did have the finish tested and it is a form of durable blueing common on industrial tools known as black oxide. I tried it but it requires a much hotter (300deg) bath and the salt solution is corrosive to everything nearby. Phosphating is only done at just below boiling (190deg) and is not corrosive. I came up with a source of solution from a Houston company who has been bought out. New owners unknown but not believed to make the solution anymore. I have the safety sheet on the original solution and it contained a very small amount of acidic nickel to promote action. I doubt any of the home mixed phosphating solutions have this nor work as well. Lots of sellers of solutions if someone wants to try it themselves. A large bead blast cabinet is essential as well as large tank. I knew one man (deceased) who "Parked" Garands in a vertical piece of pipe over a gas hot plate and got good results.

On original metal preparation, I am of the thought that the parts were tumbled in sand as were the Garands. They do not show any signs of buffing or blasting and I am sure the factory was aware of Springfield Armoury procedures. Jim, have you found anything about this in your book research?

[Gonzo 0]

Mr Scott, the black oxide finish is interesting. Is this similar to the black finish on the early WWI 1911 Colt pistols?

[Joseph Scott 0]

I am not familiar with the pistol finishes but it likely is black oxide. Several companies made it and still do. The setup requires several tanks and is expensive compared to phosphating which can be done in one tank at lower temperature.