Here are three maintenance parts on the Starweld basic welder, four on the Starweld performance 7002.  All the maintenance parts can be ordered from Stuller.  Once a year you should replace the water filter.  You're going to want to remove the back panel to get to the tank.  Unscrew the top hose and then unscrew the water filter.  Place the new filter in the tank and screw on the hose making sure the plastic washer is in position.  As a reminder the rope and welders require you to fill it with either deionized or distilled water.  The water filter for the performance is on the left side. Open the side panel, unscrew the bottom screw, and pull out the water tank.  Unscrew the hose and then unscrew the water filter.  Place the new filter in the tank and screw on the hose making sure the plastic washer is in position.  Turn the machine on and allow the water to run for 30 minutes before using the laser welder.  The protection glass needs replacing about once every one to three years.  Wipe it down once a month to remove dust and dirt from the lens.  Once the lens becomes too dirty unscrew and replace.