Aluminum

Old Irish

Well-known member
Messages
82
Good Post Points
22
Location
The River Sticks
Welder
Lincoln SW200,PowerMig 180, A/C225 with rectifier, 2 Chinese plasma, stick, tig- 1-Chinese stick w/hot start&arc force and 1 Chinese 205A mig
This is more a curiosity thing than anything, I may never need to weld aluminum again now that I am retired but maybe one of the pro's here can explain this for us.
Me and one of the guys on my crew were repairing cracked welds on a aluminum hoist basket, we followed the prescribed procedure pre heating and post heat, mig process using a spool gun. it was on a airport ramp so nothing to block the wind except for the card board shields we took turns holding. After much aggravation it appeared we were getting sufficient shielding gas with just slight sooting and frost outside the welding zone and the welds looked good but after finishing a weld and beginning the next we would hear the previous weld when it cracked. this happened on pretty much every weld. We would grind the crack out and clean everything again and weld it again, eventually we got it all done and went back to inspect frequently for many, many months and never found a cracked weld and as far as I know they are still intact. The aluminum type was unknown but we believed it to be 3000 series, I don't remember if we were using 4043 or 5356 wire and I don't recall the preheat temp but I think it was around 400F. the shielding gas was pure argon.
Thanks.
 
Top