Q&A for How to TIG Weld

You may be doing too much welding at a time, and building up too much heat. Try a small bit at a time.

There should be a chart on your machine that has specific labels on what size metal to how much amperage it puts out. If nothing is on your welder, either look in the manual or look it up.

Unlike stick or MIG welding, TIG uses argon or helium to protect the weld, so the filler rod is only comprised of your filler metal and a "coating" on the rod to protect the filler until it's used, which is usually copper.

Tungsten is a incredibly strong metal. You can clean it easily with warm soapy water.

Yes, you can use TIG welding to weld iron.

Yes, but you must use the AC current setting on your welding machine (some types of budget welding machines do not have this feature and therefore are unable to weld aluminium). You will also want to use an aluminium filler rod and grind your tungsten to a balled or rounded point (as opposed to a pointed tungsten for steel and most other metals).

Apart from referring to your welding machine's manual, setting your amp range properly can also be done via trial and error on offcuts/scrap pieces of steel that are the same thickness and composition of your actual work pieces; that way you don't have to worry about burn-through and weak welds on your final work piece, as you have already trialed different amp ranges. Strength-testing your welds can be as complex as getting them certified or x-rayed, or it can be as simple as cutting through the weld with an angle grinder and looking at the penetration and any porosity. Alternatively, you can put your test weld in a vise and strike it with a hammer to attempt to break the weld.

Since pot metal is often an unspecified alloy of different metals, it can be difficult to weld. To TIG weld pot metal you will probably want to use the AC setting on your welding machine, as pot metal is usually an alloy of aluminium (which requires AC for best results). Pot metal is generally an alloy of low-temperature melting point metals such as aluminium, zinc, tin, lead, and magnesium, among others. This makes it ideal for casting but not welding, as many of these metals tend to "vaporize" when welded; they also produce harmful fumes when welded.

It all depends on your application - MIG welding is much easier to learn and weld in many different positions, TIG welding takes much more time to learn and considerable practice and experience to make good quality welds, especially in different positions. MIG is a fast process being wire fed, whereas TIG is a relatively slow process, as filler is added to the weld manually by hand.