[Dalzani]

Hello all.

I´m from Brazil and a beginner welder. Weldingtipsandtricks is my learning guide for a least an year.

We have a motorcycle customize workshop. Here are some of machines customized by us https://www.facebook.com/FiftyNinersCustoms (sorry portuguese only). This is only an introduction.

Ok...

We have been doing steel welding, fenders and another motorcycle part for a while. Never aluminum. Our machine is only DC (TIG). Now we have a project all in aluminum, long and short welding runs between 1.5mm aluminum sheets. We are buying a AC/DC machine 200A from a local dealer, the same one than LONGEVITY TIGWELD 200 EX or SMART TIG AC/DC-200P.

We are worried about the following: This project envolves a laser cutting and a press-brake and we are expecting some gaps between the folded pieces like 0.5mm (max I hope). So I would like to ask for the experts what is the level of difficulty to weld this thin pieces with this gap and some guide lines to make this process not so hard (if is the case).

Thank you.

[Coldman]

If the gap is in a butt joint there shouldn't be a problem. The best technique would be laying the wire into the joint, hold the arc over the wire and fuse it into the two edges. That way you can avoid melting away the edges.

If it is a lap joint you should clamp the edges together - any gaps here will be a problem and result in severe distortion if you do get it fused.

[Dalzani]

Yes will be butt joint most of the time all long runs 30 to 50cm. Some corner joints but no gaps or very little ones and short runs.

I'll try this tip for sure. For the long runs, how far can I go each time to avoid a lot of warping? I have no experience welding aluminum. For carbon steel on thin sheets like this I never go more than one inch each time, wait for cooling and another 1 inch far away from the last one.

Thanks.

[Coldman]

That depends on your preparation. If it is a flat joint you can clamp chill bars from dissimilar metal like copper or steel/ss and also to restrain the edges above and below the joint. In this case you can pretty much go the whole way in one run successfully. Unrestrained it will be a problem. The better the preparation the better the result.

Tacking every 25mm helps alot too.

[MosquitoMoto]

I do moto work as well.

As others have said, add tacks quite closely together. When I use 'chill blocks' (clamping the thin sheet to thick blocks of aluminium) it helps control the heat.

If you use AC frequency of, say, 100 - 120hz and a sharply pointed electrode I find it focuses the bead on the edge very well. Using this technique you can build up the edge of a sheet that has a gap in the fitup, then once you have tightened up the gap you just weld as normal.

Get together some scrap pieces and do some practise before you take on the main job. If you are used to welding DC only on steel, it might take awhile to get used to the technique, but you will get there eventually with patience.

I will try to post up some photographs as soon as I can.



Moz

[AndersK]

How far you can go without warping depends a lot of how much shape you put into the pieces. Following pics are on a profile I made of 1,5mm aluminium. Those I tracked with 75 to 100 mm spacing and jumped between sections . I haven't ground the welds flush yet but it looks like nearly zero distorsion, fairly easy to correct with hammer & dolly if needed.

Weld parameters :
75 amps, torch switch only
150 Hz
35% EP
3/32 pointed tungsten
3/32 1070 filler

IMG_20170612_17423.jpg (41.42 KiB) Viewed 2629 times

IMG_20170731_22901.jpg (42.14 KiB) Viewed 2629 times

IMG_20170731_45958.jpg (46.54 KiB) Viewed 2629 times

Weld looks cold but it's the camera. Full penetration achieved.

It's a little bit high but I didn't have any smaller 1070 filler.
I prefer the 1070 for sheet work due to the high ductility. This bead I can hammer down completely flat without cracking. Won't do that with 4043.

[Dalzani]

Like i said, I have no experience with aluminum yet, but we do a lot of steel motorcycle fenders, extending it. Does not matter the way I do, always have some degree of warping. Needs a hammer sometimes to fix it and filler before the paint job. Maybe due the shape. I do tacks all over the piece first and them one inch in the center, one inch on one side, one inch another side and so on. Pulse does not solve but a think I get less warping.

Anyway, thanks for all information. We´ll buy the AC/DC machine this week probably and I´ll run my first tests. For sure more questions and some pics. By the way the aluminum for the project will be the 5052 alloy.

Again, thanks all.

[AndersK]

Does not matter the way I do, always have some degree of warping.

That's the nature of the beast.

I guess you already found out, since you seem to be experienced in thin sheet, even a polishing disc can warp a flat sheet.

You will find aluminium much easier to get back in shape.

Also 5052 is good practise to anneal before you try and put some shape in it. It has a tendency to age harden if the sheet has been laying in the shop a long time, hence can give you a good match.

[LtBadd]

How far you can go without warping depends a lot of how much shape you put into the pieces. Following pics are on a profile I made of 1,5mm aluminium.
Weld looks cold but it's the camera. Full penetration achieved.

Anders what is this you're making?

[AndersK]

A little wałl art project when weather is bad. Which it hasn't been for a while now....

[motox]

Anders
you should repost some of your pervious projects.
as i remember you have some beauties!
craig

[AndersK]

Thx Craig
No need to repost, they're still here

Added a link in my signature just for you

[motox]

anders
thanks great stuff. the torch box is my favorite, love the rivets.
i use them a lot myself.
craig

[Dalzani]

Hello all. I´m back.

I´m not sure about my skills with TIG welding aluminum so... We decide to rent a machine instead buy one for a while.
Today, I did my initial tests using a lot of 1.5mm thick aluminum rectangles.

My first impression... TIG welding carbon steel IS PRETTY EASY!!!

Ok, my problems:

1) After start the pudle I can run the bead easily for 4 or 5 inches on a but joint and than... A hole. I´m using 55A. I think that is the hot building up and I don´t have a foot pedal.
2) At the start and end edges is very difficult to me, ALL TIMES I´m melting down the aluminum sheet. Any trick?
3) This is only cosmetic but will be any quality (structural) issues if a did a washing weld? First pass using filler rod and a second pass with no filler. I asking this because this project needs a good appearance and the welding beads will be visible.

Thanks all.

[cj737]

Hello all. I´m back.

I´m not sure about my skills with TIG welding aluminum so... We decide to rent a machine instead buy one for a while.
Today, I did my initial tests using a lot of 1.5mm thick aluminum rectangles.

My first impression... TIG welding carbon steel IS PRETTY EASY!!!

Ok, my problems:

1) After start the pudle I can run the bead easily for 4 or 5 inches on a but joint and than... A hole. I´m using 55A. I think that is the hot building up and I don´t have a foot pedal. yep, exactly
2) At the start and end edges is very difficult to me, ALL TIMES I´m melting down the aluminum sheet. Any trick? start away from the end, light up, slide backwards with a dab to "add" filler. Near end, add more filler quickly to prevent burning out/thru.
3) This is only cosmetic but will be any quality (structural) issues if a did a washing weld? First pass using filler rod and a second pass with no filler. I asking this because this project needs a good appearance and the welding beads will be visible. works info. You can probably lower your amps too as the part is already quite hot. Same is true for the above. After first weld, the base is HOT, lower your amps some to help prevent burning up. And reduce the distance you weld to help control the heat.

Thanks all.

[AndersK]

Another trick when starting close to the edge is to lay the rod over the joint and let it protrude a few mm outside the edge. Light up at the end of the rod and let it form a ball, move closer to the edge and let it fuse with base metal.

You might need to do a few trials first to find how much protrusion you can handle. Too much and it won't fuse unless you increase current.

The most common mistake I did when starting with aluminium was too low current and to dip the rod too soon. You really need to watch the puddle and not dip until it gets that shiny mirror look. Otherwise the rod will cool it and just ball up and oxidise. When you finally get it to fuse it won't look as good as you expect.

[Dalzani]

Nice!

We are doing a lot of carbon steel welding today. Tomorrow I´ll restart my tests on aluminum. Then I´ll take some pictures.

Thanks.

[AndersK]

Forgot to mention another trick

Add an extra piece at the edge and tack all 3. Then you simply break the excess off

IMG_20170824_50257.jpg[/attachment [attachment=0]IMG_20170824_42495.jpg

]

[Dalzani]

Good ideia. For sure I´ll use it.

Thanks.

[LtBadd]

Forgot to mention another trick

Add an extra piece at the edge and tack all 3. Then you simply break the excess off

AndersK, you snapped it off before starting the weld!!

[AndersK]

AndersK, you snapped it off before starting the weld!!

So you really think I can weld?

It actually needed 2 or three bends to snap off

[Dalzani]

Hello all again.

Trying some overlaps on thin aluminum 1.5mm. I don´t know why but seems to be much more difficult then a butt joint using the same thickness. Probably the weld is good but it is VERY ugly. What i´m doing wrong?

By the way... 60A for the bead.

Thanks all.

Overlap bead

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[motox]

the sheets need to be clamped as so the edge does not lift or warp.
use a backer and tack often.
if the edge lifts heat gets under the edge and melts it away.
hope this help some
craig

[Dalzani]

No clamps was used. And just a few tacks 3 or 4 in a 35 cm extension. Next time I´ll double the tacks and buy some long clamps. You are sure a did a lot of deviations to refill the burned edges.

Thanks.

[AndersK]

No too bad, just need more time to maintain consistent speed.

When welding long flat surfaces I use a small piece of fire blanket that I fold to about 4 layers. Rest your palm at it and you won't get burned and it helps you slide along easier.