View Full Version : Finally posting pics of Aluminum welds

02-25-2006, 02:03 PM
Well, a friend of mine showed up early in the week with a bracket he was making, wanting me to weld it for him. Piece of cast aluminum to a piece of plate. It went really well, until I found out why sometimes larger tungstens are required, the one I was using got hot enough to melt and droop, touching the plate. The containation shows up in the middle of the one weld as black specks. (With the use of this bracket, the welds are more than overkill, so I just tried to clean it up some rather than gouge it all out and redo it.) Thought I'd snap some pics, both to try out the new camera, and posting too. For reference, the plate is 3/8", the locking screw is a 1/4" bolt. (The black ribs are the boxliner on my pickup, was the only 'studio' I had at hand.)

Hoping to get back at my 'projects' I bought the welder for, all 1/8" and 3/16" stuff.


You can see the specks from the contamination in the #3 shot.




02-25-2006, 03:12 PM
I found out the hard way that the contamination in the weld from dipping the electrode is VERY hard. I happened to saw through a contaminated area with my bimetal bandsaw blade, and it wouldn't cut worth a flip after that.

What's the best thing to use to remove contaminated areas from aluminum welds?


02-25-2006, 03:41 PM
That bit of contamination...I would have hit it with a 5" angle grinder with a wheel made especially for aluminum.
And I use some die grinder bits that are actually made for wood. They work really well also.

02-25-2006, 03:41 PM
If I had done it on this particular weld, I would have used my angle grinder with the segmented sanding discs. (Not sure what they are called, have all little squares of sandpaper glued to a backing disc.) They sem to work alright, but there are also aluminum grinding wheels available, but I'm not a big fan, they leave a really coarse finish, and I don't often need to remove large quantities of aluminum that way. There may also be bits of the ceramic shielding nozzle in that area, part of it melted away when the tungsten drooped and hit it. (Note to myself to get some more next time I'm at the welding supply. <grin> )


02-27-2006, 08:49 AM

Your first alluminum weld looks better than my first. It took about one spool of wire before I got the hang of welding alluminum.
The first thing is clean weld site. Second is to weld fast as that **** will melt and leave a hole like you want beleive. Perosity is a major problem. I thin tigging is the real answer.

02-27-2006, 09:32 AM
That is a tig weld. This wasn't my first Al weld, but I'm still practising and improving a lot. I used to do some of it a number of years ago, but have just got started back at it again. I'm enjoying it, but also have a lot more to learn.


02-27-2006, 09:50 AM
cleaning aluminum is the key to good welds. NO oil allowed. Grinding is ok as long as you use a wheel that NEVER touched anything except aluminum. You need to get the "scale" or "skin" oxidized skin, off also. this is formed within a few hours of machineing. Its tough as hell. The aluminum will melt and the filler material wont be able to penatrate the "skin" so you'll have a poor weld. The method prefered is using a stainless wire wheel. NEVER use the wheel on steel or anything other than aluminum or it will be contaminated and from that point on give crappy welds.

02-27-2006, 04:36 PM
Yea...tungsten is darn hard http://bbs.homeshopmachinist.net//smile.gif Out of curiosity, has anyone tried stick welding aluminum? I tried a little, i was really impressed. With the Al electrodes from lincoln and reverse polarity i thought i was welding steel. Doesn't turn colors of course, but the beads looked just the same as they did with steel and that was my first time. I just don't know the kind of quality they actually provide. The aluminum around it fatigued and cracked before the weld, but thats not really saying alot with Al. Any opinions on smaw welding of Al??