MIG welding Tip #18 ,,,learn to weld uphill
For thick stuff where penetration really counts.
Downhill is ok for thin stuff. Lets face it , downhill is easier and faster and looks better.
But for anything thicker than 1/4” , downhill is risky. Some welds will be ok while others will have cold lap and lack of fusion.
I recently ran a buttload of tests comparing uphill and downhill welding with a millermatic 251. I started at 15.5 volts and went up to 19 volts and ran uphill and downhill with both...guess what??
15.5 uphill penetrated better than 19 volts downhill.
We have all done it. I know, downhill is just faster.
I am not trying to sound holier than thou, I am just saying that if you were to cut up a 100 welds on 3/8 thick steel that were mig welded downhill, about 80 percent or more would have some lack of fusion and cold lap. Prove me wrong.
Check out the Test Results for 2 Mig Welding Techniques Uphill vs Downhill
click here for more mig welding tip articles