Mig Welding Tip #4 of 19...Use the right shielding gas
Mig Welding tip #4 is ...
Use the right shielding gas.
CO2 is good for penetration on thicker steel, but may be a little too hot for thin metal.
Use 75% Argon/25% CO2 for thinner steels as well as thick. Use only straight Argon or a Helium/Argon mix for aluminum.
Straight argon for mig welding only works on really thin stuff.Everything else welds horrible with pure argon.
You can use a tri-mix for stainless steels (Helium / Argon CO2). or even 98% argon 2% oxygen in some stainless mig applications.
There are some authorities out there who recommend odd mixtures of gas like 82/18 argon/co2...the idea is that you can use the same gas for spray transfer mig and short circuit mig.The only problem is oddball mixes are very hard to get.
If you dont believe me, just watch the deer in the headlight look from your welding supply clerk when you ask for 82/18.
A very few welding supply stores will have it, others will think you're nuts.
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