MIG tips and tricks - MIG welding Tip #6
For better penetration , keep the arc at the leading edge of the weld puddle.
This is especially true for pipe welding.
The vertical uphill part of the pipe weld usually gets penetration because of gravity keeping the puddle behind the arc. But when you get toward the top of the pipe its easy to have the arc too far back in the puddle. Always keep the arc in the front of the puddle when penetration and avoiding cold lap are of concern.
Lets be clear about this since mig welding is used for everything from thin sheet metal to thick boiler plate... When welding thin sheet metal, keeping the arc back further in the puddle can help to prevent burn thru and is used as a trick to weld downhill on auto body panels.
But welding a trailer hitch or pressure vessel needs good penetration.
That’s when you need to crank it up and keep the arc in the leading edge of the puddle.
The leading edge is where its happening .
Watching the leading edge of the puddle is the key to getting the machine settings and technique right.