Guide me to bumping technique.

[mcostello]

1 Must clean wheel with Stainless steel brush.
2 Must clean wheel with Stainless steel brush.
3 Must clean wheel with Stainless steel brush.
4 th hint is must clean wheel with Stainless Steel brush. Brush must not be used on anything but stainless Steel or problems happen.
( this is about how many times I had to learn before it sunk in.)

[go2building]

You say cleaning with thinners, lacquer thinner? Paint thinner? I use acetone or if I don't have that, denatured alcohol.
Kevin

[Gaby]

I run 200 -230 amps on my dynasty. Remember anodized aluminum is hard because the anodize acts or better yet is contamination. 200 amps should burn through that. I weld boat towers all day and it is not easy. God luck 1/8 - 1/4 is the size i use.

[FusionKing]

oops, my bad
I see you must be using a car wheel for practice!
Dirty cast underneath isn't the same as an extrusion that has been anodized tho.
You may get some halfway decent looking beads tho if it is a decent piece.
Pics would still help

[steph]

@FusionKing: yes, I only practice, this is not a real weld. The wheel was badly broke and the owner has left it for more than 3 years in my shop, so I count it as a scrape and use it for practice. Without adding filler rod there's no contamination. The contamination only appears on second, third, and the next dab. I'll try upload a pic when I have free time.

@Gaby: thank you, I'll try higher amps and bigger (#8) cup. #8 is the biggest I have.

@Go2building: yes, it's a pain thinner. Is denatured alcohol is 70% alcohol they used in medical/hospital??

@Mcostello:Few minutes before I weld the anodized, I tried to weld a cast alum, it's a 3" elbow with no problem. Laid a ..maybe 3" long beads. With the same thinner wipe and no stainless brushed. Or something I've missed here??

Thank you guys.

[Gaby]

Steph try 5356 rod they work better on anodized aluminum or contaminated aluminum. Here is a pix of o t-top i just did with 5356 rods, all anodized

[steph]

Hi Gaby, where's the pic?

[steph]

Ok, changed the setting: cup #8 (before was #6), flow 15LPM, amps 200, balance at 6, postflow 15secs, get better result,I can lay several beads (before only 1bead). But the weld look cold. Did you guys after getting it puddled move your torch arround to get bigger puddle? The puddle didnt flow easily.
Crrection: the wheel is 8mm thick.
Took a pic but dont know how to upload. Im using windows phone, Lumia900 Nokia.

[Gaby]

Did you ever get the weld done with the 250 synchrowave?

[steph]

@Gaby: I can lay beads now with Sync250DX but still not perfect, the beads looks cold at its edge. I think Sync250DX can do that okay, it's just me don't have enough skill.