Shielding gas can make or break the quality of your weld. Properly storing your shielding gas can make or break your welding shop. So when it comes to choosing shielding gas, storing it, and refilling it, you should weigh the different factors such as cost, portability, and the types of projects you’re working on. Here’s a brief overview of the options for shielding gas in your welding shop:
Who Owns Your Gas Cylinder?
In some cases welders will have limited options for their gas cylinder based on the supplier. If a particular supplier’s name is on the cylinder, then another supplier may not refill or service it. For welders in a smaller town, it may be all for the best if you only have one supplier to choose from for your gas refills.
However, if you live in a larger town or city, you may be able to pick up a used gas cylinder that you can fill up at any local welding shop or gas supply company. Just give them a call to find out what they will fill up. Keep in mind that in most cases a welding supply company is going to give you a used cylinder anyway, so it’s not a big deal to pick up a used cylinder.
What Size Gas Cylinder Do You Need?
Most supply companies will offer individuals cylinders that are 80 CF or 125 CF. Obviously, the larger the cylinder, the cheaper the gas you’re buying in bulk. In some rare cases you may be able to find a dealer that offers 330 CF, but those tend to be reserved for businesses or lease arrangements where a welder is going through a larger amount of gas.
Of course if you get a smaller cylinder, it will also be more portable and easy to move. While we recommend having a cart or holder setup in place for your cylinder regardless, that becomes all the more important once you get a 125 CF cylinder in your shop.
What Type of Shielding Gas Should You Pick Up for Welding?
When you’re working with a MIG welder on mild steel, you can certainly get by with a straight CO2 gas. There may be some additional spatter and a higher weld profile when you’re done, but if appearance isn’t a big deal, you’ll be happy with how much money you save on gas!
However, once you get Argon into the mix with CO2 (you’ll have mix options of 90/10, 85/15, 75/25), you’ll enjoy a more stable arc and a reduced amount of spatter. The finished weld will be flatter and require far less work to smooth out. The down side here will be cost, as the stability of Argon comes with a price. While the 75% Argon – 25% CO2 offers the lowest price while still stabilizing the arc, some welders who require a cleaner weld and an even stabler arc will opt for the more expensive 85% Argon or 90% Argon that also can be used in pulse and spray transfer welding processes.
The more important your weld quality and the greater variation in material or position, the more important your gas mixture will become. Whether through trial and error or asking an old timer for advice, the appropriate gas mixtures for shielding gas will change depending on the project.
TIG Welding
For TIG welding, the shielding gas you choose will vary more widely, especially based on the metal you’re working on. For instance, pure argon is common for TIG welding aluminum (and for MIG welding aluminum), but you can also use an Argon/Helium mix. When it comes to stainless steel, TIG welders typically use a mixture of Argon and Hydrogen. However, in the case of mild steel, straight Argon remains popular. You may be able to increase penetration and the fluidity of the weld pool if you add Helium and CO2 to the Argon.