MIG to TIG Transition Guide

What changes, what stays the same, and how to adapt your welding skills from wire feed to tungsten

Introduction

You have been MIG welding for a while. Now you want to learn TIG. Or maybe you need to switch for a job. The good news: MIG skills transfer. The bad news: TIG requires more finesse.

What Stays the Same

• Joint preparation - Clean metal, proper fit-up, right joint geometry
• Heat input matters - Too much heat causes distortion, burns through
• Travel speed affects bead - Consistent speed produces consistent beads
• Gas coverage is critical - Both processes need proper shielding

What Changes

1. Filler Metal

In MIG, the wire feeds automatically. In TIG, you hold the filler rod in your other hand.

You need to feed filler with your non-dominant hand, add filler at the right time in the puddle cycle, and maintain three points of contact.

2. Foot Pedal Control

TIG uses a foot pedal to control amperage while welding. Start low, increase as needed. Use it to control heat on thin sections.

3. Torch Angle

MIG: 15-20 degrees push or perpendicular. TIG: 15-20 degrees perpendicular. The key difference: in TIG you are not pushing filler.

4. Arc Length

MIG: Forgiving. TIG: Critical. Keep arc length short, about 1/8 inch or less.

5. Start and Stop

MIG: Pull trigger. TIG: Scratch start or lift arc. Requires practice.

Practical Tips

• Practice holding torch steady without welding
• Practice feeding filler with your other hand
• Set up your pedal before starting

The Basic Weld

1. Establish the arc
2. Wait for puddle to form
3. Add filler at leading edge of puddle
4. Move torch forward
5. Repeat

Equipment Differences

Process Notes

Steel: 100% argon for thick, 75/25 for thin. DCEN.

Stainless: 100% argon. Lower heat than steel.

Aluminum: 100% argon or argon/helium. AC required. Higher amperage.

Sources

• Lincoln Electric, TIG Welding Fundamentals
• Miller, TIG Welding Guidelines
• AWS D3.7, Welding Aluminum - Theory and Practice