Lincoln Plasma Torches FAQs
Practical answers on fitting, using and looking after a replacement torch for your plasma cutter.
What does the pilot arc do, and why does it affect consumable life?
The pilot arc is a small, low-energy arc that runs inside the torch before the cut starts. The gas flow pushes it out through the nozzle, and when it reaches the workpiece the main cutting arc transfers across. This lets the torch start without touching the metal.
Because the pilot arc sits on the consumable parts, it causes a large share of their wear. Keep the time spent piloting without cutting to a minimum, and do not fire the torch just to see the arc. Less unnecessary piloting generally means longer life from the electrode and nozzle.
Do I need to switch the machine off before changing consumables?
Yes. Manufacturers' instructions say to switch the power supply off at its line-disconnect switch and check that the power indicator is not lit before you touch the torch consumables. Leave it off until you have finished.
A plasma torch carries high voltage when the machine is live, so do not rely on a trigger lock or a safety cut-out in the torch alone. Let the parts cool before handling them, wear suitable gloves, and follow the instructions for your torch and your own risk assessment.
Should I put lubricant on the O-rings when I fit consumables?
Many torch manuals tell you to apply a very thin film of the silicone lubricant they specify to the consumable O-rings. The O-rings should look slightly shiny, not wet.
Too much grease is a problem because it can block gas passages and holes in the swirl ring, which upsets the gas flow and the cut. Wipe off any excess. Replace any O-ring that is cracked, nicked or flattened. Use only the lubricant your torch maker recommends, and check the manual for which O-rings need it on your model.
How do moisture and oil in the air supply affect my torch?
Water or oil carried in the compressed air can seriously shorten consumable life and spoil cut quality. It can also cause problems inside the torch and power supply. Long air lines can collect condensation as the temperature changes, so air that was dry at the compressor may not be dry at the machine.
A filter or dryer close to the cutter, kept serviced and replaced when needed, is the usual protection. Drain moisture traps regularly, and if your cuts get rough or the consumables keep failing early, check the air supply before you blame the torch.