Common Problems encountered with TIG. Part4
High Frequency starting problems have always plagued TIG welding machines, regardless of brand. HF is really hard to tame in a way and once you think you have it figured out, it comes back to bite you. At least this is how it appears from a user’s standpoint. Although many TIG welders use DC only TIG machines that are either only lift start or scratch start every day, HF starting is important in a lot of situations that require high elements of precision and contamination free welding of exotic metals and aluminum. So, being able to identify HF start issues is important for the weldor with an AC/DC TIG welder. On many machines, HF is controlled by a system similar to a coil/ignition system on an old car that used breaker point ignition. The point gap controls how well an arc starts at a specified arc gap between the tungsten and the metal. If you are trying to start an arc, and all you see is a bright “spark” like arc, then the HF is initiating, but the arc is not transferring. This can be a result of the wrong point gap. Check your owner’s manual for the correct point gap and adjustment procedure. Before you do that though, briefly touch your tungsten to the metal before starting and raise it up. Try to start again. If the arc starts, try to reproduce this procedure several times. If the problem is corrected by this action, it is probably not a point gap issue. Although this cause can be a result of some internal problem in the HF circuit, often enough as time goes by, this will naturally occur as the system wears in. The cause is hard to identify as nearly every brand has had some issue with this phenomenon. This should be thought of as a fault but rather just a slight hindrance.