May 1, 2012

Using the Henrob Dillon Type III Torch

Here’s a tool that’s halfway between too large and too small. It will, however, meet most of your welding needs.

Welding often presents a dilemma for the gunsmith. A torch that utilizes big enough tips for fairly heavy work, such as welding on bolt handles, is usually large, heavy and cumbersome. But if the unit is small and handy in size, the largest tip that it will take is usually too small for the bolt-handle type of work.

Electric welding is often too “dirty” for gun work because of slag spatter and inclusions. The obvious answer, of course, is the Heliarc type of welder. The problem with this is equally as obvious—cost. Heliarc welders are usually priced out of the reach of all but the largest shops. So the gunsmith gets by as best he can and winds up with an aircraft-size oxyacetylene unit for small work and a bigger, hard-to-handle torch for heavier work. This may be supplemented with one of the very small pencil-type torch outfits for really fine work, plus maybe a standard arc welder.

I recently ran across a product that may be a good answer to this dilemma. Called the Dillon Type III, this unit is put out by Henrob Corp. The torch unit is a compact outfit built into a pistol grip that is very easy to handle. The torch will handle tips that are adequate for anything from 1/16-inch thick sheet metal up to material well over 1/4-inch thick. It will weld bolt handles easily, and also will handle the fine jobs like sear noses, and the like. The unit isn’t cheap, however, when you include accessories.

The Dillon III has been used in the aerospace industry for some time, but is relatively unknown in gunsmithing circles. The unit uses a very low pressure out of the regulators for both oxygen and acetylene. This allows a better mixing of gases in its special mixing chamber, and results in very little unburned oxygen around the flame. The payoff here is that you are dealing with a welding flame that exerts very little pressure on the puddle—reducing blowthroughs, while the lack of unburned oxygen really cuts the scale formation in and around the weld. This is something the gunsmith will appreciate and is why the Dillon is called “the poor man’s TIG” by many.

Courtesy, American Gunsmith

Courtesy, American Gunsmith

The Henrob torch comes packed in a plastic box with an assortment of tips and accessory items. The main thing we would add is a second wrench.

Four welding tips supplied with the unit, combined with the unique mixing chamber design, give the user a wide range of heats to weld many different thicknesses and types of metals. The unit welds such tough-to-handle metals as stainless steel, cast iron, and aluminum with a minimum of expertise required. The low pressure of the flame makes aluminum welding much easier, and cast iron can be welded with little or no preheating—again something that one would expect more of a MIG- or TIG-type welder.

The very low pressure (around 4 psi) that this unit uses makes it economical, costing about half what other welding torches do in gas use. As I said, the unit isn’t cheap to acquire, but when you consider that it can replace a couple of different sizes of conventional welding torches, the price looks much more reasonable. The Henrob unit comes with four tips for conventional welding; one tip for soldering; two cutting tip attachments, one with guide wheels and a wrench; all in a fitted plastic case. The four tips will handle almost any welding job facing the gunsmith.

The torch uses a slightly different setup for cutting. There is a separate tip that injects the oxygen stream onto the molten metal during the cutting process. It works very well, cutting metal up to 1 inch thick. Once you get used to it, the separate oxygen tip is very efficient and easy to handle. A set of wheeled guides comes with the unit for precise cutting.

Its cutting ability may be handy, but the Dillon’s primary use by the gunsmith is as a welder. The pistol-grip handle puts the weight of the tool in the palm of the hand, allowing a great deal of control. The feel is somewhat foreign to those of us used to the long, gangling type of conventional torch, but after using this one, you won’t want to go back to the conventional type at all. I really like the weight in the palm of the hand instead of waving around at the end of 10 inches of torch body.

The only possible drawback to the pistol grip is that the hand is rather close to the job when working on large pieces or cutting heavy metals. There is a heat shield that attaches to the torch and extends around the hand to shield it from this heat when needed. The average gunsmith will find very few occasions when the size of the work necessitates the heat shield. The shield is lightweight enough that it is hardly noticeable when attached.

Courtesy, American Gunsmith

Courtesy, American Gunsmith

The insides of the torch can’t get a lot simpler than this. A wide range of tip sizes allows the torch to do just about any job in the shop. It could even replace some of the more conventional units you use.

Another attachment that comes with the torch kit is a propane-type tip that duplicates the propane torch for soldering. The tip uses acetylene and air to produce a flame that is exactly the same as that from the standard hobbyist propane torch, thereby eliminating another tool.

One complaint about the torch: I would like to see two of the dual-duty wrenches included. The wrench has one end for tips and the other end for the body of the torch. However, the body often must be held while the tip is broken loose, which takes another wrench. A second wrench would make the Dillon’s use a little easier.

I welded everything from bolt handles to small sear noses with the Dillon. It did every job easily and with less slag than my standard torches. I question if the weld approaches TIG quality, but it certainly is less “dirty” than what I’ve gotten with conventional torches.

The low pressure allows a great range of uses for the torch with the various tip sizes. The only torch I have that the Dillon didn’t replace is a very small pencil-type torch that I use for very fine work. Other than that, the Henrob replaced both my large conventional torch and the small aircraft-type torch. I would definitely recommend this unique and well made tool to any gunsmith—amateur or professional.

Once one gets the feel of it, very fine, precision welding is possible with a minimum of slag and scale formation. More-over, welding seems to be faster, with less heat transfer into the work. I’m told that this is due to the low oxygen content of the secondary flame, which tends to shield the weld puddle and insulate it from the surrounding area.

The Henrob Dillon Type III torch is worth the money, in my opinion. It comes with a 30-day return policy if you don’t like it, and the company offers a two-year guarantee. It’s certainly worth a look.

Click here for American Gunsmith Website