WM BLITZ VIDEO #9 MIG Welding Overhead PrimeWeld MIG180 on 115volt
A36 steel Material thickness was 3/16"
I used settings of 18 volts and 236 ipm wire speed with .035" ER70S6 wire for the first weld and then reduced the wire speed to 200 inches per minute for the second weld after allowing the piece to cool off.
I like to test welds using what is called a "macro etch test" where you cut the weld, polish out rough scratches and then etch using a solution designed to reveal the difference in base metal and weld metal.
this macro etch test is especially helpful when done immediately after welding when the puddle is still fresh in your minds eye.
For me, since I make welding videos, I can watch the puddle and correlate the macro etch test results with what I saw in the puddle...and then share that with you...and hopefully, we all learn something and are better off.
The most common mistakes I see in overhead mig welding are:
- using lower settings for fear of the puddle sagging.
- Using a long stickout due to fatigue of arms or in an attempt to see the puddle better.
- poor gun angle
I like to use settings that are almost as hot as I would use flat on the bench except I sometimes reduce wire speed by around 10-15% to achieve a flatter profile.
The first weld was done at 236 inches per minute...while the second was done a 200 inches per minute.
200 ipm is 15% less wire speed.
A long stickout reduces amperage and softens the arc and while you might see the puddle better, the weld often piles up.
A stickout of 1/2" or less works best
Gun angle can be dead nuts straight in at 90% or can be tilted slightly for a slight push or pull angle.
Dont get all hung up thinking either pushing or pulling is right or wrong.
Both work provided you avoid extreme angles.