Bending metal can be pretty simple with basic hand tools if you’re doing thin materials, but once you get past sheet metal and into thicker materials over 1/8″ it can be difficult to make sharp bends in metal without extreme force. In the past heating metal with an Oxy-Acetylene torch was one of the few ways you could bend thicker materials with ordinary shop tools. This method was common when every garage had a set of torches on hand. In today’s world a gas torch is less common as most use a plasma cutter or electric welder to cut and weld metal. In this tutorial we show how you can turn your TIG welder into a heating device and bend thick gauge metals with your Eastwood TIG welder at home.
In this demonstration I will be using a piece of 5/8″ thick and 3″ wide mild steel bar stock. In order to put a sharp 90 degree bend in this metal I’d need a very heavy duty press brake if I wanted to cold-bend it. In this method we will mounting it in vise leaving the area we’re heating about 3-6″ above the jaws of the vise. If you clamp the metal too close to the vise it will tend to soak up the heat and it will take much longer to heat the metal you want to bend. If I’m using a foot pedal or variable switch on my TIG torch I start by setting my welder amperage slightly below what I would weld the material with. If I want a sharp bend in the metal I like to grind my tungsten to a sharp point as it will focus the arc better. For softer, more gentle bends I will flatten the tungsten tip as it creates a wider arc and will heat a larger area. I start an arc and keep the torch just a little higher than I would when welding and begin going back and forth across my bend line.
After a few passes back and forth on the bend line I begin to move my tungsten further from the bend line and I increase the amperage this will begin to really put heat in the metal and get it to malleable state. Be sure to move your torch back and forth fast enough that you don’t begin to melt the surface away too much as we want heat through he entire profile of the metal and not burn away the surface.
As you begin putting more heat into the metal you can have a helper (wearing a welding helmet for protection) or yourself begin to pull or push on the metal to begin bending. The metal should bend with moderate force, if it takes extreme pressure to move it, continue to heat. You want the bend line to get just about red hot all the way through and it will move with light pressure. Once the metal begins to bend you can begin lowering the amperage on the torch and bend the metal quickly while it is still hot. For thicker metals like shown here you may need to lower the amperage slightly and continue to wave the arc back and forth over the bend line to keep heat in the metal.
If you’re bending to 90 degrees or more you may need to pull the tungsten further away from the bend line or start with additional tungsten stick out. As the metal gets to the desired bend you can slowly drop the amperage and heat down. If needed you can strike an arc again and reheat to adjust the bend if needed. This process is quite quick and with a little practice can be a quicker, cleaner way to bend metal than even with a Oxy-Acetylene torch.