How to Weld Steel Tube

Welding thin steel exhaust tubing requires patience and the correct equipment to get a sealed weld. The difficult part of welding thin walled steel tubing is maintaining your weld puddle without overheating the connection will result in the puddle melting through the tubing. With a properly set up MIG welder and a little practice, you easily create a sealed weld joint on the thin diameter steel tubing. MIG welders are widely available at rental stores or for purchase at your local welding supply retailer.

Things You'll Need

• MIG welder
• Spool of .023 welding wire
• One bottle of 75 percent argon/25 percent carbon dioxide shielding gas
• Adjustable wrench
• Safety glasses
• Welding helmet
• Welding gloves

Instructions

1. Read the owner's manual for the welding machine to determine how to change the feeder wheels over to accept the .023 welding wire.

2. Spool the welder with the .023 solid welding wire after you switch the wire feeder wheels.

3. Open and close the valve located on top of the bottle of shielding gas to clear dirt and debris from the threaded area.

4. Turn the threads of the MIG welder gas regulator clockwise to attach the regulator to the bottle of shielding gas. Set the adjustable wrench to fit the regulator nut and lock the nut to seal the connection. Open the valve to send gas to the MIG welder.

5. Turn on the welding machine and place the grounding clamp on a piece of metal.

6. Point the tip of the MIG gun at the metal and depress the trigger of the MIG gun. Listen to the sound coming from the weld area between the MIG cup and the grounded piece of metal. Adjust the heat and wire speed settings until you hear a sound similar to eggs frying in a pan.

7. Place the ends of two pieces of steel exhaust tubing tightly together and ground the steel tubing with the grounding clamp.

8. Wearing your safety glasses, place the end of the MIG wire protruding from the tip of the MIG gun against the center of the weld joint and depress the MIG guns trigger for 1 second to create a tack weld. Roll the pipe, placing tack welds around the weld joint.

9. Put on your welding helmet and welding gloves.

10. Rest the wrist of the hand that you are holding the MIG gun with on a firm flat surface and grasp the tacked pieces of pipe with the other hand.

11. Align the wire extending from the MIG gun with the weld joint, flick your head forward to lower your welding helmet, and depress the trigger of the MIG gun.

12. Move the MIG 1/8th of an inch and stop to let the weld puddle build, when the weld puddle reaches around 1/8th of an inch tall, move the MIG gun another 1/8th of an inch. Continue the process, turning the pipe as needed to expose more weld joint until you weld around the entire weld joint and reach the spot where you began welding the joint of the steel tube.

13. Allow the joint to cool thoroughly before you move the welded tubing.