Here is a short tig welding guide for beginner tig welders:
- Prepare the power source – on the front panel of the welding machine, check each switch carefully (this includes the power switch, the SMAW/GTAW mode switch, the amperage control panel/remote switch, the output panel/remote switch, the ARC force/balance control switch, the preflow and postflow switch, the START mode switch, the weld current control or amperage current control, the remote amperage control receptacle, the AC/DC selector/polarity switch, the high frequency control, the primary overload circuit breaker switch, and the spark gap assembly switch). Connect the torch to the front of the machine as well as the regulator and gas hose.
- Prepare the weld joint – this consists of the following steps:
- Prepare the base metal – the metal should be cleaned as thoroughly as possible using either manual mechanical methods or liquid or vapor cleaners.
- Arrange the parts to be welded – the two pieces to be welded should be arranged together and clamped.
- Preheating the base metal may sometimes be required depending on the thickness of the metal; this may be done with an oxyacetylene torch, heating coils and blankets.
If welding aluminum, the extra steps below must be taken:
- Remove the surface oxide from the aluminum using either mechanical or chemical methods.
- Clean both sides of the joint.
- The filler rod should be cleaned prior to use.
- Choose the correct type of tungsten and determine the proper diameter of the tungsten electrode; use the smallest possible diameter for the amperage using. The tungsten must also be dressed prior to use, as if sharpening a pencil. Attach the tungsten to the torch.
- Choose the right filler material, shielding gas (this should be 100% argon), and amperage (for aluminum, use AC current and a ceriated, orange identifying tungsten band or gold identifying tungsten band; for steel, use DC straight polarity and a red identifying band tungsten), and gas flow rate.
- Determine and set the high frequency mod and hold the torch about 1/16 inch from the metal at a 15 degree angle (always use a push technique with the torch); strike the arc (to do this using high frequency, the electrode should be held about 1/8 inch from the metal and the pedal depressed) and wait for it to stabilize and form a puddle on the two pieces; add the filler material to your puddle and when you see them combine/join discontinue. Guide your puddle with the weld-joint, all the while maintaining a consistent arc length and travel speed appropriate for the desired bead shape
- For stainless steel, keep the heat as low as possible as a general rule.
- For titanium, shielding of the weld when temperatures reach 1200 F is required, and a trailing gas is also needed.
- If you see smoke or sparks forming from the weld puddle, you must stop and clean both the weld joint and tungsten.
- Do not have contact with the filler rod at any time during the welding procedure to avoid an electric shock.
- When get to the end of your welding pass and stopping the arc, let the shield gas afterflow (or post) flow cool the weld puddle.