To weld mild steel choose an american welding society classification wire such as er70s 6 which has a weld puddle that wets out nicely.
Welding 18 ga sheet metal.
When welding mild steel a good rule of thumb is to set the amperage level at 1 amp for every 0 001 of thickness.
Just grab a piece of sheet metal to get the heat set correctly and go to town.
When the material is 18 gauge and thicker you may be able to use a 030 inch wire.
A good heat setting for 1 8 6011 rods on thin material is about 80 90 amps.
Continue the same way along the sides of the piece of sheet metal.
As a rule when mig welding sheet metal never use a body filler metal that is thicker than the base metal.
Keep the stick out short stickout of your mig wire is important when welding any type of metal but especially sheet metal.
Say if you are welding an 18 gauge stainless steel sheet that is 2 2 feet in size to repair the side of your tank start by creating a weld that is 1inch long then skip 6 inches and then create a 1 inch long weld.
Everyone is different but those settings will get you in the right ballpark to weld sheet metal.
Holding the tip too far from the surface will cause the wire to have to come out too far to touch the metal.
Most of the light gauge sheet metal work will require the use of 023 or 24 inch while if you have a sheet metal having a gauge of more than 18 gauge then a 030 inch wire would be the most ideal.
So if you are welding 12 gauge mild steel with a thickness of 0 100 you would set the machine at 100 amps.
Mig welding is the preferred method for most automotive bodywork and since sheet metal is the thinnest of metals a large expensive mig unit is usually not required.
For thinner gauge sheet metal like 18 or 20 gauge we suggest 023 6mm wire in your mig welder.
Metal thickness amperage settings.
It s recommended to use a 023 or 024 inch wire for most light gauge sheet metal work.
For 3 32 7018 s it s about the same.
However if you are dealing with materials that are 18 gauge or thicker one should be able to use 030 inch welding wire.
A er70s 6 wire would be most ideal for welding mild steel.
Gas metal arc welding gmaw is an effective method for joining light gauge metals such as carbon steel and austenitic stainless steel.
The majority of the sheet metal welding i ve done was with a 90 amp 110 volt welder.