5 Biggest TIG welding Best Practices  ...

Gas Shielding on Stainless

What are the 5 things that make the most difference in TIG welding?

1. cleaning the metal
2. good gas shielding
3. sharp, clean, and properly prepared tungsten
4. tight arc length
5. proper amperage control

There are other details but these are the 5 things that play the biggest role in ensuring high-quality, precise, and good looking TIG  welds.

1. Cleaning the Metal

Proper surface preparation is one of the most important aspects of TIG welding. TIG welding requires a clean and uncontaminated surface because contaminants like dirt, grease, oil, rust, paint, or mill scale can:

• Lead to porosity in the weld.
• Introduce impurities that weaken the weld joint.
• Cause arc instability or erratic performance.
• Take all the fun out of TIG welding

How to Clean the Metal:

• Degreasing: Use a degreaser or acetone to remove oil, grease, or other organic contaminants.
• Grinding or Sanding: For heavy oxide layers or mill scale, use a grinder or sanding disc.
• Wipe with a Clean Cloth: After cleaning, wipe the metal with a clean cloth to remove any residue.

Why it Matters: Clean metal enables proper fusion a lot better than dirty metal, prevents weld defects like porosity or inclusions, and improves the overall appearance and strength of the weld.

2. Good Gas Shielding

Shielding gas, typically argon or sometimes an argon-helium mixture, protects the weld pool, electrode, and surrounding metal from atmospheric contamination (oxygen, nitrogen, and hydrogen). These gases can:

• Cause oxidation or discoloration.
• Introduce porosity or inclusions in the weld.
• Lead to weld embrittlement or cracking.

How to Ensure Good Shielding:

• Correct Gas Flow Rate: Use a flow rate typically that is typically between 2-3 times your cup size in cubic feet per hour (CFH). Too high a flow can create turbulence and pull in air; too low a flow may not adequately shield the weld.
• Use the Correct Cup Size: A larger cup provides a broader shielding gas coverage, which is especially useful for 4130 chromoly, tool steel build up,  or when welding stainless steel or titanium.
• Check for Leaks: Ensure all connections in your gas delivery system are tight and free from leaks.
• Work in a Draft-Free Environment: Even a slight breeze can disrupt the shielding gas coverage.
• Proper Torch Angle and Distance: Keep the torch at the correct angle (typically 15–20° from vertical will do but torch angle can be forgiving if a good tight arc is maintained ) and maintain consistent distance from the weld pool. Arc length rule of thumb is diameter of tungsten or slightly less.

Why it Matters: Proper shielding gas prevents contamination, ensures weld strength, and enhances weld appearance, avoiding oxidation or discoloration.

3. Sharp, clean, & proper Tungsten

The tungsten electrode is the heart of the TIG welding process. A sharp tungsten tip helps to focus the arc, creating precise and controlled heat input.

Why Tungsten Sharpness Matters:

• Arc Control: A sharp tip produces a stable, narrow arc, which is critical for detailed and clean welds.
• Weld Penetration: The focused arc delivers precise heat to the joint, improving penetration and weld quality.
• Reduced Contamination: A sharp tungsten minimizes the risk of touching the weld pool or contaminating the electrode.
• Better Aesthetic Welds: Consistent arc control produces smooth, clean welds with better bead appearance.

How to Maintain a Sharp Tungsten:

• Grind Properly: Grind the tungsten electrode to a fine point using a dedicated tungsten grinder or a clean grinding wheel. Always grind in the direction of the tungsten's length, not across it, to ensure a consistent arc.
• Correct Angle: The grinding angle should usually be around 25–30° depending on the application (sharper tips for low-current welding, more blunt tips for higher currents).
• Choose the Right Tungsten: Use the appropriate tungsten for the material (e.g., thoriated, ceriated, lanthanated, LaYZr, E3).   2% lanthanated, LaYZr, and E3 are good all around tungsten that work on all metals.

4. Tight Arc Length

Arc length refers to the distance between the tungsten electrode and the workpiece. In TIG welding, maintaining a tight arc length is critical for control and weld quality.

Why a Tight Arc Length Matters:

• Heat Concentration: A tight arc focuses the heat directly where it is needed, improving weld penetration and reducing distortion.
• Gas Coverage: Keeping the arc length short ensures the weld pool remains protected by the shielding gas.
• Weld Bead Appearance: A tight arc produces a more consistent and smooth weld bead.
• Prevention of Undercutting: A tight arc minimizes the risk of the arc wandering or creating excessive heat on the edges of the weld.

How to Maintain a Tight Arc Length:

• Practice: TIG welding requires precision and a steady hand. Practice to build muscle memory for maintaining consistent arc length.
• Electrode Stick-Out: Ensure that the tungsten extends the correct distance beyond the gas cup (typically , stickout should be around the same as the inside diameter of cup or less…depending on the joint and application).
• Focus on Technique: Hold the torch steady at a slight angle and move at a consistent speed to maintain the arc length.
• Use a Foot Pedal: A foot pedal allows you to modulate amperage, giving you finer control when working with a tight arc.

5. Proper Amperage Control

Even though TIG welding can be done using simple scratch start with no amperage control other than what you set on the machine.

And it can also be done using a simple torch switch with no amperage control.

But for most people, having a foot pedal or torch mounted amperage control will help you get better results.

Amperage needed on the very ends of a joint is different that what is needed for the middle area.

And being able to taper off amps on thin metal is a big help.

A foot pedal generally provides more control than a torch mounted switch.

A good practice for setting amperage on the machine is to set the machine around 20% more than the maximum amperage needed and use the foot pedal to control amperage by the look of the weld puddle.

It takes practice and experience to read the puddle but eventually you will be able to add or reduce amperage just by the way the puddle reacts.

Conclusion

Obviously there are other details to consider to get the best results TIG welding, 

These are four of the best practices to start with

1. cleaning the metal, 
2. good gas shielding, 
3. sharp tungsten, 
4. tight arc length
5. proper amperage control