Chapter Ten Finishing and Bluing

In the preceding volume of this series, I described the methods and materials used in the hot "nitrate" process of bluing (or "blacking") parts of a firearm. In this volume, 1 will present sufficient information to enable you to finish weapons with both the comparatively slow nitrate process, as well as a faster rust-type bluing (or "browning") procedure.

Let me mention here that you must take every precaution possible to protect your eyes and skin from the more caustic bluing formulas that follow, particularly the "hot" solutions. When mixing any bluing formula, add water to it slowly by means of a long handled dipper so that any chemicals that spatter out then will not reach you. An even safer method is to place a funnel in the end of a five foot section of pipe and pour the water through it. Some chemicals listed here are extremely dangerous when handled carelessly.

Note that considerably less equipment is necessary for the quick rust-type of finish than with the nitrate blue. In fact, for the faster method, one tank approximately five inches high, five inches wide, and long enough to accept the longest part to be blued is adequate. For the pistols described in this book, a tank length of 14 to 16 inches will suffice. It can be heated on a kitchen stove if no other heat source is available.

But if you anticipate doing very much bluing, it is advantageous to make three tanks together with a rack to hold them, with individual burners for each. Construct the tanks from any material that can withstand the temperature needed to boil water. Trays from discarded room planters, poultry feeders, or even a section of rain gutter with endcaps brazed in place are fine. Another source for suitable tanks is old rocker arm or valve covers at the automotive salvage yard.

Mark these tanks numbers one, two, and three. Tank number one is the degreasing tank. It will contain a strong

Here Is the bluing tank set-up that I use In my shop. From left to right are the cold water rinse tank, bluing tank (with thermometer), degreaslng tank, and hot water rinse tank. Not shown Is the oil tank along the wall behind these tanks.

Hot Caustic Bluing Problems

lye or caustic soda solution, or a tri-sodium phosphate solution. Make the last solution by mixing one cup of tri-sodium phosphate with 2V2 gallons of water. Keep aluminum parts out of either of these solutions. They will pit or even disintegrate in these baths. Use household detergent for degreasing aluminum parts.

The number two tank contains a neutralizing bath of either pure distilled water, or water with a little lime added.

The third tank is used for boiling the parts in water, in accordance with the "fast method" process. Fill it to a depth of at least three inches with distilled water. Do not use ordinary tap water for this step, since it almost always contains impurities, which cause blemishes to develop on blued surfaces.

Before the components of a firearm can be blued, they must be highly polished. If you have Volume One of this series, follow the same polishing sequence it presents.

This procedure is relatively simple. After filing all nicks, dents, and scratches from the surface of the part, use progressively finer grits of abrasive cloth to polish it with a crosswise "shoeshine" motion. Then use the same cloth to polish it with a lengthwise motion until the crosswise

My bluing tank burners were made from pipe and mixing valves salvaged from discarded gas stoves and hot water heaters. Two rows of holes were drilled In the top of each pipe.

Bluing Tank For Sale

marks are polished out. Repeat with the next finer grit, eventually progressing to crocus cloth, until the steel has a shiny, chrome-like appearance. Finally, check the part under a strong light for blemishes or dull spots. These must be removed if a professional-looking finish is expected.

Immediately prior to bluing, clean all parts completely, making certain they are free of oil or grease. Wear clean cotton gloves throughout the cleaning operation, since human skin secretes oil and sometimes acids. An imperceptible layer of these secretions, which may prevent the bluing solution from working properly, will result if you handle parts without gloves.

Prepare to blue the barrel by making hardwood plugs that fit into each end of it. These plugs should be at least 3/4 inch in diameter, and long enough to serve as handles. The premanufactured dowel rod available at most lumber yards is ideal for this purpose. Using a wood lathe, turn a shoulder on one rod a few thousandths of an inch larger than the barrel's bore diameter. Make the plug for the muzzle end of the barrel five or six thousandths of an inch greater than the barrel's groove diameter. Grease it lightly and drive it into the bore, allowing approximately 1/2 inch to remain between the muzzle and the plug shoulder, insuring that the end of the muzzle will be acceptably blued also.

Drive a similarly-fitted and greased plug into the chamber end of the barrel. Properly done, the two plugs will prevent any trace of the bluing solution from reaching the inside of the barrel.

Most of the other parts are handled during bluing by wooden plugs fitted into holes present in the respective parts. Similarly, screws and bolts may be handled during bluing by drilling appropriate holes in wood strips, then screwing these screws and bolts into the holes. Small parts that have no holes or openings present another problem. Handle these by the free end of a stiff wire wrapped around an area of the part that does not require bluing.

Before you start the actual bluing, bend three U-shaped brackets from heavy wire, such as coat hanger or welding rod. Position one of these in each tank, to prevent larger parts from contacting the bottom of the tank. I also recommend making a pair of hooks from about 3/16 inch diameter steel rod. Use the hooks to both place the parts in the tanks and remove them.

Presently, it is possible to purchase commercial bluing solutions which will satisfactorily color and protect the metal if used according to directions. Herter's Belgian Blue, Stoeger's Yankee Blue, and Brownell's Dicropan IM are three of the more popular home-bluing solutions on the market. Prices and container sizes vary, but all produce nearly identical results by following essentially the same application technique.

Because this book is intended for a time when such commercial preparations may not be available, the following formulas are included so that you can mix your own bluing solutions.

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