Blowing Holes In 20 Ga Sheet Metal With My Mig

I have been having problems with burning holes through the metal i have tried to weld for a second then stop then weld it works to a point and sometimes i get a nice weld but usually i burn a hole in the metal also i been stitch welding the metal and it is still warping in.

Blowing holes in 20 ga sheet metal with my mig. If it s blowing through quickly then maybe the power is set too high on the welder. If after you hit the trigger and the arc is established you start to blow a hole or the surrounding metal starts to melt too fast let off the trigger. When mig welding sheet metal it is important to set the proper parameters to prevent warping and burn through or else it will create excess heat and easily blowholes on the metal. If you are butt welding try to minimise the gap between the two sheets.

This can happen due to inexperience or because turning the heat up too high. If your welding wire is too thick it will take more heat to melt the wire than the substrate and can make it even more prone to blowing holes in the panel. If the parts fail to touch each other for even 1 16 inch you have created a hole that invites burn through and a gap that can t absorb the heat. Either way there are certain things that a welder needs to be aware of when mig welding sheet metal.

The aim with this technique is to melt a bit of metal and then let it cool slightly before melting the next and it s a handy way to avoid blowing holes. The biggest mistake a welder can make is to blow a hole in the panel. Keep in mind during the welding process it is important to direct the arc right at the center of the weld puddle and don t do movements like whipping or weaving as it may cause warping and burn through quickly. Im replacing quarter panels on my car and have been practicing butt welding on the old panels.

I got a bunch of holes to weld up on my rear frames rails on my 68 mustang are thin gauge soda can style. I have welded holes using a copper spoon backer but these holes i am unable to use a copper backer. The thin metal technique is a non continuous process that is used for thin metal such as car body panels. To avoid rework follow the measure twice cut once rule.

For thinner gauge sheet metal like 18 or 20 gauge we suggest 023 6mm wire in your mig welder. If you start right at the edge where you really want the weld to be you will likely burn the edge and blow it away before the bottom base metal ever gets molten. I also want to fix some small holes in my door but i am so afraid to make a mess or blow through the hole. Imagine a butt weld on 20 to 24 gauge metal.

Mig welding sheet metal.