TIG Welding: Tips To Properly Weld Sheet Metal

DCWI_logo1-300x151TIG welding has so many applications; one of the most common is in the aviation and airline industries. In such work, TIG welders usually use weld sheet metal. If you are welding sheet metal for aircraft applications, or for any other that you can think of, consider the following TIG welding tips to ensure that you get the high quality work that is needed.

Just Follow These Simple TIG Welding Tips

Follow rule of thumb – To estimate required heat output, use the rule 1 amp per 1 thousandths inch of carbon steel thickness. Stainless steel and other nickel-based metals need less heat because nickel is a poor heat conductor. For magnesium and aluminum, which are excellent conductors, increase heat output slightly.

Chill out – Use copper chill bats with argon ports. Both the copper and gas draw heat away from the weld area. While it’s okay to use a copper shoe attached to a steel structure, make sure you configure the bar so the copper touches the well-meant. Take care that you do not put copper in direct content with cobalt allows as this may cause issues in high-temperature applications.

Cover your backside – When welding sheet metal, treat most applications like titanium. Titanium always needs shielding the backside of the weld to prevent oxidation. In thin applications, shielding gas on the backside of the weld reduces heat output. It also improves weld quality by eliminating metal surface imperfections that could potentially be a source of cracking high fatigue applications.

Love the back-step – The standard practice in TIG welding involves pushing the weld puddle in one continuous direction for the entire length of the weld. With back-stepping, the welder breaks up the seam in parts to dissipate the heat. Do not confuse the back-step method, which is a planned series of steps along a single joint with the randomness of skip welding.

Super size it – Other sheet metal applications usually require a size #7 TIG cup. For welding sheet metal in aerospace applications, #15 cup or larger is required. A large cup gives better gas coverage of the weld puddle and heat affected zone, which reduces total heat input and improving bead quality. It should also improve bead appearance.

Lens crafter – Always use a TIG torch with a gas lens. The lens smoothens the gas flow and prevents turbulence, which widens the area of gas coverage. If needed, it allows increased electrode extension beyond the cup. Extending the electrode will allow it to reach into the corners and give better visibility of the weld area.

Mind The Gap  Of  Your TIG Welding

To do maintenance on some parts, you should cut them to gain access and re-weld the part while maintaining the original dimensions of the part. All parts shrink when welded, so make sure that you plan ahead. Good fixturing, R&D work and experience can give an indication of how to pre-gap a part before welding.

To the point – Electricity likes to come off a point. Nothing focuses an arc more than needle-sharp tungsten. Sharp tungsten directs the heat where you want it. Also, you do not weld with contaminated tungsten; it is a recipe for rework. Having a standard on lanthenated electrodes for all your applications should help.

Always Look For Extensive TIG Welding Experience

If you are looking to get TIG welding done for aerospace application, or for whatever industry, but you have limited TIG welding experience, it would be best that you contact a certified welding company to do it for you.

Reuben Salazar

About Reuben Salazar

My name is Reuben Salazar. I’m president of Dan’s Certified Welding, Inc. (DCWI), a family-owned business founded in 1976 by my parents, Dan and Mary Salazar, and centrally located in the Los Angeles, CA, area. For over 35 years, we’ve continued to deliver high quality, craftsmen-specialized welding to each of our customers across the country. We’ve served hundreds of manufacturers and machine shops who lacked in-house welding or approved, qualified welding professionals. DCWI combines the most innovative large corporation ideas with the customer-oriented values of a family-owned business. You will not be considered “just another number” at our company. To us, YOU are the #1 most important aspect of our business! We pride ourselves on taking the time to fully understand the needs of our customers, making them feel welcome, comfortable, and appreciated, so they have no doubt their welding projects are in capable, professional hands.