Gas for TIG Welding Steel

What is the best gas for TIG welding steel?

Argon...100% argon

This is a great video on TIG welding carbon steel

TIG welding carbon steel tubing

Argon is the most versatile and most commonly used shielding gas for carbon steel, 4130 chromoly, high strength steels, stainless steels, nickel alloys, aluminum, magnesium, titanium, cobalt alloys, and even gold and silver.

Some people try to TIG Weld carbon steel using MIG gas which is usually 75/25 argon/Co2.

It doesn't work. 

Sure you can stick 2 pieces of metal together tig welding with mig gas but it usually turns into a mess of sparks, bubbles, porosity, and its just frustrating.

Pure Argon is the way to go and is by far the best gas for tig welding steel.

Renting vs owning gas cylinders for welding

Larger cylinders last longer between refills, but they are heavier and less portable.

Owning an argon cylinder is a lot like owning a propane gas cylinder for your gas grill.

When its empty, you just swap it for another full tank.

Sometimes the tank might look ragged even if you swap a new looking tank.

Renting vs. Owning

• Renting is usually better if you weld frequently and use quite a bit of argon.
• Owning is usually better if you don't weld regularly and don't want to pay monthly rental fees while you go long periods without welding.

For TIG welding at home or in a small shop, owning a cylinder (80 CF or 125 CF) is usually the best option because it avoids monthly rental fees while providing enough gas for multiple projects. However, if you need higher volume (250 CF or larger) and constant refills, renting might be the way to go.