bamaranger
New member
Can a S&W nickeled revolver barrel, be refinished to matte blue, or perhaps recoated with something like Black T with satisfactoy results?
The sulfuric acid process is the most common method for anodizing. The sulfuric acid anodize process films range from .0001"-.001" thick. The overall thickness of the coating formed is 67 percent penetration in the substrate and 33 percent growth over the original dimension of the part. It is particularly suited for applications where hardness and resistance to abrasion is required. However, where parts are subjected to considerable stress, (such as aircraft parts), the possible presence of the corrosive acid residue is undesirable. The porous nature of sulfuric acid films prior to sealing is used to particular advantage in the production of colored surface finishes on aluminum and its alloys. The porous aluminum oxide absorbs dyes well, and subsequent sealing helps to prevent color loss in service. Although dyed anodized films are reasonably colorfast, they have a tendency to bleach under prolonged direct sunlight. Some of the colors are: Black, Red, Blue, Green, and Gold. For defense/military and homeland security applications, Anoplate offers olive drab green anodize, urban gray anodize and black anodize. Parts can be treated chemically or mechanically prior to anodizing to achieve a matte (non-reflective) finish.
The pH should rise slowly during operation, since cathode efficiency is slightly lower than anode efficiency. Sulfuric acid should be used for pH adjustment, although hydrochloric acid may also be used with the added advantage of maintaining the chloride ion concentration. However, the disadvantages of using hydrochloric acid include not only the higher amounts required but the escaping hydrogen chloride gas, especially from a hot, air-agitated solution