Frequently inspect all parts of the welding machine. Tighten loose connections and inspect cables, electrode holders and ground leads for wear, cracks, and damage. Immediately replace those with excessive wear or damage. Note that excess cable length and coiling cables around ferrous metal, such as a table leg or pipe, also causes erratic arcs and drifting weld parameters. Use quick disconnects to add or subtract cable as needed to avoid these problems.
Guns. A gun is not a hammer, but operators often use it as one. Banging may loosen connections inside the gun and lead to erratic arcs. Inspect guns every six months, tighten loose connections, and blow out any particles.
Cables and liners. Clean the cable assembly after finishing a spool of wire, or about twice a week. Disconnect the cable from the feeder and check for a secure connection. Blow out the cable, directing air into the contact tube end. Tap the cable every few feet to loosen any residue trapped in the liner and blow it out again.
Without regular cleaning, the liner will eventually clog and seize the wire. This causes feeding problems, typically slipping, that can cause the wire to burn back to the contact tube. This may cause a bird’s nest at the drive rolls. If the liner is cleaned and still there still are wire feed problems, the liner is likely worn and needs replacing.
Drive rolls. Inspect the drive rolls when the cable is cleaned. If dirty, remove and clean them with a wire brush. If deformed, replace them. In addition, check the inlet and outlet guides and replace them if they are deformed from wire wear. More pronounced wear on the inlet guide may indicate the need to realign the wire spool hub assembly.
Water coolers. Maintain proper coolant levels. Rather than water, use a blended coolant from the manufacturer. It solves problems related to sludge build-up and foaming.
Gas hoses. Porosity in the weld bead and poor bead color can result from insufficient shielding gas coverage. Examine hoses regularly for leaks, wear, and loose connections. Immerse pressured hose in water to check for leaks. Repair a leaky or worn hose by cutting out the damaged area and splicing. Do not use tape.
Regulators. Remove a faulty regulator from service for repair after closing the cylinder valve. External gas leaks, excessive creep (when delivery pressure continues to rise with the downstream valve closed) and faulty gauges (pointer does not move off the stop pin when pressurized, nor returns to the stop pin after pressure release) indicate a faulty regulator. Do not attempt to repair a faulty regulator; send it to the manufacturer’s designated repair center.
Engines on welding generators. Basic maintenance includes changing the oil, oil filter, air cleaner, and fuel filter. Check the owner’s manual for service intervals, as this varies greatly between gas and diesel engines.