Micro Welding

To The Rescue
19

Evolution Armory staggered tooth key seat cutter milling slide
rails on a Colt 1911 frame, after micro welding.

Work on enough guns and eventually it will happen, a missed cut, a cutter crashes into a work piece or a client brings in an obsolete gun with a broken part. For a long time the solutions were limited to buy a new part or fabricate one. Welding was an option, but usually limited to large pieces, and the same with silver solder, where heat can distort small parts or worse, harden areas.

Now there’s a better way. Micro welding is not new, it’s using very fine weld wire with very low amperage to limit arc and flow size of the weld puddle. Pullman Arms in Worcester, MA, an offshoot of Micro Arc Welding, started using micro TIG and laser welding for the firearms industry in 2011. As you can imagine this is not your usual ham-fisted type of industrial welding. Scott Malkasian, owner of Micro Arc/Pullman is an artist when it comes to welding. We’re talking about laying down 0.001″ beads of weld from a 0.005″ wire. So small all the work is done with the aid of a microscope.

Pullman was started when Malkasian got a call from a firearm manufacturer with 400 bad frame castings needing a flaw repaired. Seeing a need for his service and a good business opportunity, Malkasian applied for his manufacturing FFL as Pullman Arms and was able to take on the contract. From this point on Pullman has expanded their services to gunsmiths in need of precision welding and parts repair. They offer services like crack repair, fractured part welding and material addition using both TIG and laser.

Walter P38

Walther P38

Walther P-38 with a cracked slide, the crack micro welded and the final finish work by Pullman Arms, bringing an old war-horse back to life.

Walther P38

Little Heat

The big advantage to both is scale and heat. For example a cracked slide from a WWII P-38 with original numbers is laser welded back together using a 0.005″ 4140 rod using milliseconds of laser light and minimal heat to avoid warping the slide. This allows the gunsmith to retain the originality of the pistol after refinishing. A vintage Colt SAA comes in for a broken indexing star on the cylinder. No problem, a new one is fashioned using Micro TIG and shaped to match the original.

Pullman also offers more common services like welding 1911 frame rails and beavertails. They also fill in Millett duel crimp sight holes. The precision in which they make repairs is the great part, with minimal clean up, smooth welds and no heat migration. I’ve used Pullman for a few years on projects I just could not, or was too scared to tackle. Recently I botched a checkering job on a 1911 triggerguard, which is not an area known for thickness. After a bit of laser welding I had a new clean surface to work with, thicker than what I started with.

The machines are very high tech and expensive, but like anything, you get what you pay for. The welds are so small and perfect you save time and money in the end with shorter machining and finishing time. Micro Arc does a lot of high tech welding for industry, medical and aerospace, keeping the shop busy. Owner Scott Malkasian, an avid hunter, likes the challenge of working on firearms. If you ever run into a weld job you just can’t tackle look up Scott.

Specific Tooling

After welding comes the re-machining job, requiring some special cutters. I use a number of off-the-shelf cutters, but gunsmith-specific cutters are becoming more available. One firm I use is Evolution Armory in New Hampshire. They offer cutters specific to 1911 work, like a carbide key seat cutter for frame rails with offset teeth allowing for cutting the top and bottom of the rails, instead of standard key cutters.

How about a cutter making 10 rows of 25 LPI horizontal lines on the 1911 front strap or mainspring housing with your Keller checkering jig — in one pass. Or serration cutters for slides, 0.30″ wide at 40 LPI in one pass. All the cutters are carbide and are specially designed for gunsmiths by gunsmiths. Dovetail cutters are also available with larger shank diameters and extra flutes. They cut clean and shorten set up and machine time.

For more info: https://www.pullmanarms.com, Ph: (508) 926-8730;www.evolutionarmory.com, Ph: (603) 973-3780; www.brownells.com, Ph: (800) 741-0015

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