[Physh1]

Question for you other welders. I was just messing around getting my Miller spool gun (Spoolmate 3045) setup on my Millermatic 210 MIG welder and started welding up some scrap aluminum. After doing the metal prep/cleaning and laying some beads I noticed a lot of carbon dust residue on the welds. It wipes off easily and the beads are clean and even with good penetration. Being the first time I've MIGed aluminum (using 100% argon of course) is this carbon residue the result of the argon cleaning the remaining contamination? All else is good...welds look great...I was just a little thrown by the amount of carbon residue from MIGing aluminum...

Cameron

[willys36@aol.com]

Bump.

[Physh1]

Thanks for the bump....I did figure out the deal...mainly from tinkering around...

The carbon residue is the result of the argon cleaning the remaining contamination. I was just using a SS brush to clean it and when I welded it the aluminum was much cleaner after...led me to believe is was contaminate. Testing it, I did a few welds on some aluminum that was brushed and wiped w/ an acetone rag and the resulting weld was the same but w/ less carbon residue left to clean. It's all about clean base metal...

Cameron

[ratlover]

There are many contributing factors.
are you pushing or dragging the puddle? aluminum welds will turn out brighter if you push the puddle with the gun at about a 15-20 deg. angle. Also the amp/volt setting on the machine is important. if you do not have enough wire speed the wled will also be dirty. The weld should be clean with no need to brush if machine is setup properly. Try increasing amperage and weld with argon at about 35 cfh. One other trick is to observe the wire as it exits the contact tip. it will curl around in a certain direction from being spooled on the small diameter spool. turn the gun to orient the direction of travel with the direction that the wire curls out of the nozzle. this too will increase brightness. good luck.