The ONLY Settings That Matter for Tig Welding Stainless Steel

Tig Welding stainless steel has many important variables that someone needs to consider to get good results. The material is expensive, and very sensitive to certain details, so let’s make the most of your practice material, and the time you spend welding on it. The key to doing this? Keep it simple with settings.

Considerations for Amperage Settings

When setting up for a welding exercise, it’s vital to consider amperage in relation to the material thickness you are using to practice. This is a chart that I use in my program when teaching people how to set up for Stainless Steel. This will give you a ballpark of where to start with amperage in relation to the material thickness you are using.

Adjusting Amperage During Welding

Using a foot pedal or thumb trigger provides the flexibility to control amperage as you weld. I usually recommend to set your amperage slightly higher than necessary—generally 10 to 20 amps above your estimate. By monitoring heat closely and making adjustments with your foot pedal or trigger, I generally use a touch extra heat at the start of your weld, and once you start travelling, you can fine-tune your amperage on the fly. Watch for signs of inadequate fusion, such as poor transitions between filler material and base material, this will indicate that you may need slightly more heat in relation to the amount of filler material, or material thickness you’re using. The goal is for smooth, consistent edges indicating perfect heat input in relation to material thickness and the amount of filler being used.

The Importance of Post Flow

Post flow refers to the gas that continues to flow from the torch after extinguishing a weld. This is always important no matter what type of metal you’re welding, but this is especially  crucial for stainless steel welding, as the glowing red hot material is at risk of oxidation if exposed to the atmosphere. To prevent oxide from forming (that grey, dull look we are all familiar with,) ensure that the welding area is completely shielded by gas during the cooling process. I recommend to set the post flow time a few seconds longer than you might initially think necessary. Keep your torch cup close to the workpiece while the gas cycle is running. You want to completely cover the area as long as it is glowing red hot. If the metal is shielded at this temperature oxide will not have a chance to form, this is what will give your stainless welding a shiny and reflective look, as well as possibly forming some colouring.

One frequent mistake is moving the filler material or torch away from the weld area prematurely. This can lead to immediate oxidation.  The main rule of thumb here is to completely cover the welding area with gas the entire duration it is glowing red hot, plus a couple extra seconds.

Managing Gas Volume

The actual amount of shielding gas used during welding is another critical setting that can influence your results. This will be set and adjusted with your Working Pressure gauge on your regulator. The size of the gas cup plays a significant role in determining the appropriate gas flow. Generally, the gas flow should align with the size of the cup being used. For example, a number 15 cup requires a different gas volume than a number 8 cup. However it will also be important to make sure that gas levels aren’t set too high. Excessive gas flow can lead to an unstable (wobbly) puddle, making puddle control really difficult to maintain as you travel along. Here's another chart from my online program that you can use to reference. 

Adjusting for Differences in Heat Input

For larger welding areas requiring more heat, I recommend to switch to a larger cup and increase gas flow to ensure proper shielding. For narrower joints or thinner material, switch to a smaller cup with your gas volume adjusted down accordingly.

Wrapping Up

Good looking stainless steel welding requires a careful balance of settings, including amperage, post flow, and gas volume. By understanding and taking these elements into consideration, you can improve your outcomes and produce high-quality welding. If you are looking to learn even more about getting a proper start with Tig Welding Stainless Steel, register for my free online class RIGHT HERE and attend at your own convenience on demand, for free.

Have fun, and Happy Welding.

Dusty