FergalFarty
Member
- Messages
- 203
- Location
- Bristol
At my evening course the other night had my first go at aluminium. What a disaster!
I managed to do one nice bead (middle bottom), but whenever I tried the mitre butt joint, couldn't get a puddle going or it would blow a hole. Also, there was lots of soot around the welds. Gas flow was 10lpm, 75A on 2mm box section. The instructor reckoned the metal was contaminated even though I'd just cleaned it with a brand new disc. The weld on the bottom right is his, not mine.
Could it be some contamination on the back of the metal? This was some painted ally from my scrap bin. Any ideas what I'm doing wrong?
I managed to do one nice bead (middle bottom), but whenever I tried the mitre butt joint, couldn't get a puddle going or it would blow a hole. Also, there was lots of soot around the welds. Gas flow was 10lpm, 75A on 2mm box section. The instructor reckoned the metal was contaminated even though I'd just cleaned it with a brand new disc. The weld on the bottom right is his, not mine.
Could it be some contamination on the back of the metal? This was some painted ally from my scrap bin. Any ideas what I'm doing wrong?