Welding pot metal aluminum
Posted: Thu Dec 17, 2009 4:58 pm
This week at work, a co-worker brought me a broken door handle from a beat up 87 ford that he wanted to know if I could weld for him for free. I said sure.
I discovered that it was aluminum, possibly pot metal aluminum from the looks of the broken edge, with a chrome type coating. So, I beveled the edges a bit and went to it.
The miller machine at work has very faded numbers, and writing, and since its the only place I've ever tig welded, I cant say much about the machine settings. All I know is that I used a 1/8 tungsten that we normally use for aluminium, 1/8 aluminum rod, a number 8 cup, and argon. Now the thickness of the door handle was only about 3/32, so I started out with an oversized rod and tungsten, but thats all I had to work with.
I used a balled tungsten
I was using a slightly green tinted auto -shield from northern. The 50 doller house brand one.
So I pulsed(like zap zap zap) the workpeice a bit to clean it(a steady drag would have melted it), and I noticed the arc was a bluish color. It normally appears green when aluminum welding, and the tungten turned black, but the metal did not appear to be contaminated.. After I started the bead though(still using the zap zap zap method), the arc turned back to green and the tungsten became shiny again.
When I was done, I noticed that on the back of the workpiece, the chrome plating had puffed up ridiculousley. I ground down the bead(it looked shitty) almost flat, waited for it to cool and took it between my two hands and pushed and pulled as hard as I could, and after a minute of straining, it snapped.
The weld snapped down the middle ussually indicating good penetration but a lack of bead thickness.
So I got at it again, and I cleaned/welded the back side this time too, for extra toughness. The bead went down fine, easier then the first time, but still looked bad. I ground the front side of the workpeice down and wire wheeled it, and I didnt try to bend it.
But I noticed this time the entire chrome plated surface that hadent been ground away, had bubbled up very badly, looking like one of the self applied window tinting jobs that teenagers do(and I did once too). Also, the area around the weld had little tiny potholes, even though I did not(i think) expose that area to the welding arc.
So, is there any way to get a better result with this, or is there another welding process which will work better?
-Rick
I discovered that it was aluminum, possibly pot metal aluminum from the looks of the broken edge, with a chrome type coating. So, I beveled the edges a bit and went to it.
The miller machine at work has very faded numbers, and writing, and since its the only place I've ever tig welded, I cant say much about the machine settings. All I know is that I used a 1/8 tungsten that we normally use for aluminium, 1/8 aluminum rod, a number 8 cup, and argon. Now the thickness of the door handle was only about 3/32, so I started out with an oversized rod and tungsten, but thats all I had to work with.
I used a balled tungsten
I was using a slightly green tinted auto -shield from northern. The 50 doller house brand one.
So I pulsed(like zap zap zap) the workpeice a bit to clean it(a steady drag would have melted it), and I noticed the arc was a bluish color. It normally appears green when aluminum welding, and the tungten turned black, but the metal did not appear to be contaminated.. After I started the bead though(still using the zap zap zap method), the arc turned back to green and the tungsten became shiny again.
When I was done, I noticed that on the back of the workpiece, the chrome plating had puffed up ridiculousley. I ground down the bead(it looked shitty) almost flat, waited for it to cool and took it between my two hands and pushed and pulled as hard as I could, and after a minute of straining, it snapped.
The weld snapped down the middle ussually indicating good penetration but a lack of bead thickness.
So I got at it again, and I cleaned/welded the back side this time too, for extra toughness. The bead went down fine, easier then the first time, but still looked bad. I ground the front side of the workpeice down and wire wheeled it, and I didnt try to bend it.
But I noticed this time the entire chrome plated surface that hadent been ground away, had bubbled up very badly, looking like one of the self applied window tinting jobs that teenagers do(and I did once too). Also, the area around the weld had little tiny potholes, even though I did not(i think) expose that area to the welding arc.
So, is there any way to get a better result with this, or is there another welding process which will work better?
-Rick