Thin walled exhaust tubing can be difficult to weld, but choosing the correct welding process will make the task less daunting. Each welding process will weld thin walled tubing. Tungsten inert gas (TIG) welding is the easiest way to weld thin walled tubing, but unless you have experience with TIG or gas welding, the learning process can be time consuming. MIG, although harder to set up, is readily available and has less of a learning curve than TIG welding.
Put on your safety glasses and leather gloves.
Spool the MIG welder with the .023 diameter welding wire. Using a lighter welding wire, reduces the amount of heat require to melt the wire electrode and will lower your chances of blowing through the thinned wall tubing. Connect the bottle of shielding gas to the welder to finish setting-up the MIG welder.
Turn on the welding machine. Read the welding machine guide to determine a starting point for the welder's amperage and wire speed. Connect the ground cable to the worktable. If your work table is non-conductive, wood for example, clamp the ground onto one end of the thinned walled tubing.
Put on the welding hood.
Place the pieces of thin walled tubing together. Ensure that the pieces fit together tight. Do not leave a weld gap between the pieces of tubing.
Align the wire from the tip of the MIG gun with the tubing joint. Flick your head down to lower your welding hood. Depress the trigger of the MIG gun to create a tack to hold the tubing together. Place additional, evenly spaced tack welds around the connection.
Place the hand that is holding the MIG gun in a comfortable position, with the MIG wire aiming at the weld joint. Steady your welding hand, with your free hand. Allow yourself ample room to move both of your hands around the accessible section of the weld joint.
Flick your head down to lower your welding hood and depress the MIG gun's trigger. Pull the MIG wire straight away from the weld puddle 1/8th of an inch. Stop and allow the weld puddle to catch up to your location. When the weld puddles reaches your location, move the MIG gun another 1/8th of an inch. Repeat the process until the joint of the pipe is welded solid. If you blow through the thin walled tubing, stop welding. Let the weld joint cool, and place tacks around the hole. Build the tacks until you fill the hole.
Allow the weld joint to cool before handling.
