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For many people, titanium has a near-mythical repuataion for strength. So much so, in fact, that most view it as a sort of magic "unobtainium" capable of of any task, but only available to the most expensive and technologically advanced devices. In reality, titanium is not impossibly hard to obtain or to work with. With standard machinist skills, or even advanced woodworking skills, you too can work with this impressive metal.

Pure vs. Alloys

Titanium is available in to forms: Commercially Pure (CP) and various alloys, usually alloys of aluminum and vanadium. CP titanium is cheaper than most alloys, but has characteristics that are far inferior to those of most alloys. The most commonly available alloy is 6Al-4V, so named because it contains approximately 6% aluminum and 4% vanadium. This alloy is tougher and harder than CP titanium, as well as retaining all the other desireable properties of the material (high strength-to-weight ratio, non-corroding, etc.). For the purposes of this article, I will always be referring to the 6Al-4V alloy unless otherwsie specified.

The Cost

Titanium is is by no means the cheapest of materials available, but it is by no means the mot expensive either. At the time of this writing the going price of titanium is usually about $0.50 per cubic inch, though this price may increase with thin sheets or tubes and the like, which are more difficult to manufacture. On top of this you will probably need to purchase some quality machining tools, if you wish to do the work yourself. Nitrided steel tools (the gold-colored variety you may have seen before) are a good choice, and are available in most hardware stores for a not-unreasonable price. It is assumed that you alread posess the equipment to do whatever maching you wish to perform, i.e. a drill or drill-press for making holes, a hacksaw or bandsaw for cutting, etc, and already know how to use them proficiently.

Traditional Machining

Titanium can be machined by hand, if you have the proper technique. The basic idea is to use as much pressure as possible with as low a machine speed as possible. If you are drilling, set the drill to a very low speed, and then push as hard as possible. Likewise for bandsaws and similar tools. This is likely to generate a lot of heat, so use lots and lots of lubricant to cool the tool and the metal. This is doubly important, as titanium oxidizes at a relatively low tempertaure, which significantly weakens it. The reason for this unusual method is that titanium has a very hard surface, but is fairly elastic. If the "tooth" of the tool cannot dig into the titanium deeply enough, it will instead simply compress the metal and skid off instead of cutting into it, meaning you will generate lots of heat and dull your tools without actually diong anything to the titanium itself. By going slowly and with lots of rpessure, you ensure that the tool takes a good, large bite out of the metal.

This is, however, rather hard on your tools. You will go through drill bits and saw blades much mroe quickly than you will with most any other material, and this unavoidable. For this reason, many machine shops will refuse to machine titanium, or will charge an unusually large amount for the work. While their fears are not baseless, they are typically an overraction--titanium is tough, but it is by no means impossible, and should not cause a ridiculous amount of wear and tear upon the machines.

Titanium can also be welded, but great care must be taken. As mentioned, titanium oxidizes at a fairly low temperature, and any kind of welding will exceed this temperature. The trick is to use inert-gas welding, such as MiG or preferably TiG welding, and to use as a high a volume of inert gas as possible. It may help to construct a semi-enclosed area to work in and build up the inert gas concentration even higher, but for most purposes this is not really necessary for a skilled welder with good equipment.