The life of plasma cutter consumables depends on the number of factors. This includes the number of cut starts and stops, cutting amperage, cutting speed, air quality, and operator skill level. The number of starts and stops causes more wear on consumables than actual cutting time. For plasma cutters using air you can expect a consumable life of between 150 to 300 starts until the plasma cutter nozzle wears out. Plasma cutter nozzle - The orifice in the cutting torch tip constricts the plasma arc to a very small diameter. The plasma gas provides a thin cooling boundary layer between the arc and the nozzle. If the gas flow is too slow or the current level is too high then the arc may short inside the cutting tip. This is called double arcing and it will leave gouges inside the cutting tip and shorten consumable life. The purpose of the orifice is to constrict the plasma arc, and pin point it into a very narrow stream. This constriction focuses the plasma stream and increases the plasma arc temperature. A worn orifice does not constrict the plasma arc as much which results in a lower plasma arc temperature and a wider kerf. Lower temperature means longer cut times and reduced productivity for consumables. The consumables for higher amperage plasma cutters use different nozzle sizes for different amperage settings. Using the wrong nozzle size on a high amperage plasma cutter will cause premature nozzle wear. Gouging also increases the wear of plasma cutter tips. Edge starts provide the maximum life for plasma nozzles. It is suggested to try a test cut using high amperage and then adjust the cut amperage and speed to get a good quality kerf. It should be possible to adjust amperage to achieve a good quality cut with minimal slag and in this way increase the life expectancy of consumables.. Arc length will affect nozzle life of plasma cutter consumables. Holding too long an arc will cause premature nozzle wear reducing the useful life of consumable items. Make sure the air supply is clean and dry. Contaminated air can shorten consumable life and cause premature Plasma cutter torch failure. After some practice the operator should be able to achieve a skill level that maximizes the life of plasma cutter consumables. Adjusting the plasma cutter for optimum current output and is something that is learned through experience.