This TECH TIPS is provided by the experts at ESAB.
TIG is oftentimes used on jobs where there are strict specifications for the codes or aesthetic purposes. If you’re familiar with TIG, then you know it’s a complex process and can lead to a few questions and mistakes along the way. To prevent them, here are some common ones often asked.
1. What is the perfect torch angle for TIG? Straight upright is perfect, but difficult to achieve if you want to see your weld. Instead, aim for an angle that is comfortable, yet less than 60 degrees. Too steep of an angle will lead to an unfocused arc, the argon will be deflecting, and the potential for weld defects and poor bead profile increases.
2. Why do my TIG welds look burnt or gray? This is caused by a forming of excessive oxide on the surface of your TIG weld. Excessive heat input – and excessive amperage – and inadequate gas coverage or contaminated gas can all contribute to this problem.
3. Why is my TIG weld bubbling? The bubble is a gas pocket caused when gases are trapped and before the weld pool solidifies. The gases then expand to cause the bubbles. Avoid this by keeping the weld surface clean, checking your gas flow and equipment, and keep an eye on your voltage / arc length.
4. Why is my TIG weld cracking? There are several possible reasons: 1) the temperature is too hot during welding and cooling too fast; 2) the weld joint is very constrained and there is not enough weld metal to prevent cracking or there are low melting compounds contaminating the weld metal or 3) excessive hydrogen is getting into the weld through the atmosphere, shielding gas, filler metals, or mill scale which usually leads to delayed cracking.
5. Why is my TIG weld spattering? Spatter typically occurs in MIG welding but can happen in TIG. Oftentimes it’s due to dirt and contaminants on the surface, which can cause molten metal to spit and splatter. Before you weld, be sure to clean the surface.