Trying to tig a bracket onto frame of truck. Just tacked right now.
Truck is around 3/8 thick ....... the bracket steel is around 1/8th.
Whats the right way to approach this ? In terms of setup (Amps) .... and preheat or not etc ......
Started out setting to around a split of 150A .... and really it just soaked into the larger metal and blew out the thinner metal.
Really depends on the joint configuration, I'm assuming it's a t type configuration with the 1/8" sticking out from the 3/8" piece?
I would make sure the fit up is really good. The 1/8" piece shouldn't have any gaps. Any place the plate isn't touching is going to make it blow out easily. To me that joint comes down to where you focus the arc and using the filler to cool the puddle where and when you need it. If you can, you can also place some aluminum or copper behind the 1/8" piece to soak up some of the heat.
Grinding away that rust before you tacked it up would be a good idea as well.
Like other said using some aluminum backing/heat sync would be a good idea as well. Focus the arc on the 3/8 and wick the puddle up to the thinner material.
