Did you take a stainless steel wire brush to the weld zones before welding?

 

Here is a aluminum weld I made with my spool gun on 1/4” aluminum with 3/64” 5356. I ran a stainless steel wire wheel over the plates before welding. There is still some black smoke.

 

http://www.thefabricator.com/article/aluminumwelding/how-to-recognize-minimize-weld-smut

 

Pretty normal. Wire brush the area, wipe down with acetone for best results. To soot wipes right off.
More of a concern are your weld parameters. Some of those welds look pretty cold. Some have no fusion on one side.

 

Thanks for the replies. I decided to get to work on the trailer and check for replies at the end of the day (evening). When I did the practice beads on scrap I got very little black soot (smut). I noticed that some beads were cleaner than others, the ones done in flat or horizontal position. Also the overhead beads were the best, shiny with almost no smut. The vertical downhill ones are the worse. They are covered from start to finish with the stuff.

I am having trouble in some joints where the gun seems to feed erratically leading to a loss of a clear puddle resulting in poor fusion as seen in the picture. The wire feed control is in such a position and is so sensitive that it can be moved slower or faster as you handle the spool gun leading to over penetration or no penetration. Knowing this I now have trained myself to be cautious when I pick up the spool gun and while using it. I think I may be using too small a wire for the job as the practice runs were all with .035 and for the repair job I'm using .030. Can this have an effect on the penetration and fusion of the weld bead?

The practice beads I did when testing the then new spool gun were really shiny and had a nice contour just like the one posted by CEP above. This trailer has a lot of vertical downhill beads tying the side panels to the studs with vertical joints all over the place.

Its good to know though that the smut is to be expected and does not harm the metal properties. I used a stainless wire wheel on an angle grinder to brush all the joints prior to welding.

 

therrera,

Even running down hill you have to push the puddle.

I'm not familiar with the Ready Welder spool gun you mentioned but it would be my guess that there's a way to tighten up that wire speed control knob (dial) so it's not so easily accidently moved off from where you want it set. Might need to take the spool gun handle off to figure it out. Do you have the owners manual for that spool gun?

I also think you'd find that 4043 wire will run better for you.

 

The speed control knob is a well known issue with the Ready Welder. The newer ones are supposed to have something the help. On the older ones some people put a o-ring under the control knob to make it harder to move accidentally. I tried this with mixed results.

The Ready Welder is a ok spool gun. Definitely cheaper than most of the other offerings. I used one for a while and it's possible to make good welds with it. But it's a bit more finicky than say a 30A. But then the 30A can have feed problems as well.

 

we weld 10 aluminum trailers a day, smut is always a problem, dirty aluminum, to much gas, wind blowing in open doors, to fix, we just spray with 50% vinegar 50% water and it all comes off.

 

My quickish 2c...

1) I've tried 5356 and 4043...the 4043 runs much easier on my 30A. Do you absolutely need 5356 due to alloying?
2) Please clean the aluminum before welding. I use the same procedure as tig...ss brush, then acetone for oils removal.
3) You can't go wrong using a torch to preheat.

i) I've found that as you weld long beads, the aluminum will heat up. So either you set the welder to get good start heat, and are too hot by the end, or you set it to finish up well, and you are too cold at the start. Preheat helps to moderate this temperature differential so your entire bead can be close to the right heat input. For your stitch welds it's not as big a concern as for long beads.

ii) Even though the AL can look clean and dry, it may contain moisture. Most of the stuff I weld looks great, but you can actually see the water come out of the metal and receed before the torch as you preheat. Sometimes there is so much it drips off the material.

3) Agree with the above that you are too cold. Increase output on the mig control, then set the wire speed. You just have to find a way to get the wire speed consistent. Also, you may need to control the nozzle to work distance better. Keep the nozzle as close as you can (within reason). When the wire speed is right, the sound of the arc will be a more consistent hiss than arc/spark. If the 2 pieces are dissimilar thickness, direct the arc more at the thicker piece.

Hope that helps

Chay

 

the biggest problem you have is running downhand cant do it with alu dont care what anyone else says about it dont work flat out you will never get a decent weld with it. Get a good stainless hand brush dip it in acetone and scrub the area your welding if that doesnt work get some aluma prep acid wash. Always push the alu weld try to keep a 7deg angle i run 50cfh of argon with a 5/8 nozzle alot say thats to much but it works the argon is what cleans the weld durin the welding process. As for filler metel you can go to a 4000series wire smaller say 030 it will wet in nice on what your doing an is way easer to work with for me id end up using 5356 047 but thats cause im to lazy to swap over 20lb spools and rethread my gun

 

You are right. I don't agree that 50cfh through a 5/8th nozzle cleans the metal. In fact cover gas does not clean the metal that I know. It is the arc that cleans/lifts off contaminants. But I do say if that recipe works for you, by all means use it. My CobraMig uses a 5/8 nozzle and we have great success with 26cfh. My MillerMatic350 uses a 3/4" nozzle and 35cfh seems the be the right flow for it. It also fits along standard cup flow parameters for mig and tig. On the other hand Helium dictates a very high gas flow.

Your 7 degrees is spot on. So many try to go to even a 45 degree angle to see the weld and fudge it up.

 

Agreed, downhill spoolgunning can be an art, this is a sander funnel we built for our wacky mechanic

and it was a little bit of a bitch to get our spoolgun to run the way we wanted, all 1/4, downhill (vertical in some places) flat and over head, and the key was to push at a slight angle, not pull!

 

Agreed, downhill spoolgunning can be an art, this is a sander funnel we built for our wacky mechanic View attachment 977941

and it was a little bit of a bitch to get our spoolgun to run the way we wanted, all 1/4, downhill (vertical in some places) flat and over head, and the key was to push at a slight angle, not pull!

That's cool!

 

its not an art its just doesnt work plan and simple you may of layed down a nice beautiful looking weld but it has zero structual strength to it. yea everyome says i run alot of gas but it sure works for me as for the argon im going to have to look it up but from what i recall the argon reacts with the heat and arc blah blah some chemical thing happins thatt cleans it

 

I think a beautiful bead that does its job is art, call me a nut if you want

pushing the bead "pushes" the argon over the weld puddle, while pulling does the exact opposite, leading to oxygen entering the weld puddle.

 

Some confusion here, so I'll give my opinion to add to the mix.

abec; " the biggest problem you have is running downhand cant do it with alu dont care what anyone else says about it dont work flat out you will never get a decent weld with it."

Nope not even close to reality. In fact Abec, himself said

abec; "Always push the alu weld try to keep a 7deg angle.."

So if someone pushes the down hill it works fine. Abec's first statement is a little "wide brush action" in terms of his real practice; push aluminum. Push it up, push it down, push it sideways, push it anyways, just push the weld and it works great! I've pushed about 4-5,000 hours of aluminum down hill with a series of Cobras, Python and one old King Cobra in wires from 0.035" to 1/16" (all 5356) and those boats seem to be doing fine after four decades? There's quite a few of them banging around and you'd think there'd have been some sort of weld failure problem in forty years (?) but there's not.

In fact, I used to regularly hang the skiffs up on one side to get the down hill of the transverse ribs and side frames and use 0.045" on the 1/8" to 1/8" weld PUSHING the weld down as fast as I could pull the Cobra.

and the OP agrees! "and the key was to push at a slight angle, not pull! " he says- but abec is not reading the posts??

Abec; "its not an art its just doesnt work plan and simple you may of layed down a nice beautiful looking weld but it has zero structual strength to it."

I think aluminum MIG downhand works fine, and so do the hundreds of boats I built doing it. I agree that you need to push that downhand weld, not pull it, so does the OP with his spool gun. I hope Abec will modify his stance a bit, we're doing it, and I did a weekly break bend for a few decades on my own welds in the shop when I was building full time. The welds in question looked good and were fine in bend tests, so abec; you're welcome to your own practices but for those of us who have used this technique for years and years, it will be hard to give up on your opinion of that weld.

Wouldn't all those break bend tests show up the weld as deficient? The tests caught bad argon, mislabeled wire, contaminated cleaning rags, steel wire brushes, and lots of other defects, but the downhand weld didn't show up as a poor weld.

If you're discussing dragging or trailing downhand, well there's not much disagreement. But if you're saying that a pushed down weld in aluminum MIG is a poor weld; I don't think that's a valid point of view in my experience.

Of course like you say in your first reply, you don't care what anyone else says, and I'd agree with you there too.

Cheers,
Kevin Morin
Kenai, AK

 

If you put enough of something on it holds and not to get into it with you kevin but id put my alu skills against your any day ive built hundreds of boats too some have 20000 plus hrs pounding off the b.c. coast I've also built 120ft by 8ft alu bridges with 120psf load rateings. So you could say i have some experence with it. The downhand welds produce poor quality welds .

 

Abec, neither the OP or me or anyone I can find on the thread said YOUR welds were at question. I'm not saying that now- either.

You're the only one who's pronounced, sight unseen, no break bend evidence and no personal contact on some one else's welds. It is not an issue if you're boats are doing fine, it is an issue if the sand box or my (down hand welded boats) are OK?

You seem to be mixing things up here a bit? You alone have made the statement that one weld technique you don't care to use is not valid... IT is widely used by the entire boat building industry, it is therefore you alone who are questioning others, and without any basis for this overbroad assertion.

In your replies, you mention that you've got lots of work out there... fine and good, and I'm not questioning your work, or your welding methods choice- up hill in all cases is fine with me. Abec you seem to miss that you alone are the one person in this thread who's made the assertions that another welders' methods are not valid... OK you don't use them but nobody has said

"Abec's bridges, boats, and welds are can't work- doesn't matter what he says they won't' work- they're all dangerous."

So you don't have to get defensive about your body of work with its fine uphill welds. Not one soul I read here has questioned your work. You are the only one that is questioning others' work- and doing it sight unseen.

I don't want to get into it with you either, and you may notice that I'm not now, have not, and don't question if you choose to use uphill welds which in your judgement are more suited to your work. Fine with me.

I do think its a little out of line to make statements that are easily demonstrated to be wrong and not reconsider the fact others with fine bodies of work, including major boat building manufacturers, use the method you're saying 'can't' work!

You may as well say "There is no other power supply brand except Lincoln; none but Lincoln will weld!" or "There is no possibility that anyone can weld that bead with a Chi-com welder- ever!" or some other sweeping and over generalized statement that is easily proven not to be true.

I'm still trying to point out that your earlier statements about downhand aluminum MIG not working are not factual; they needed to be followed by the simple "IMO" note. Failing to do that, you double down on the next post and insist that an experienced welder doesn't know what he's doing!

abec; "its not an art its just doesnt work plan and simple you may of layed down a nice beautiful looking weld but it has zero structual strength to it."

Nobody but you is making sweeping statements deriding the OP, and you're just completely wrong in your statements about downhand aluminum MIG. You may not like to use that bead, and that's fine with the world, but your remarks are not true; they're your opinion of your preference only not fact.

Cheers,
Kevin Morin
Kenai, AK

 

if i hurt someone feelins are came off harsh i apologize it wasnt my intent to be a dick.