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skintkarter 05-25-2019 08:08 PM

First attempt at gas welding aluminium
 
4 Attachment(s)
Well I finally had my head in the right space I thought to pick up the torch and try some O/A welding of aluminium.

Fluxed the top side of the join with the flux mixed to a thin paste with Isopropyl Alcohol. Tacked the coupons together just with the torch, cleaned and tapped flat on the stump.

Re-cleaned everything and re fluxed (just the top surface of the join). Obviously some tension in the panel, as the start of the weld began to crack behind me - and perhaps not enough pre-heat as with tig cracking. Possible issue also with starting the weld in front of the first tack.

Material is 1.6mm 5005 and filler rod is a sliver cut from the edge of the sheet.

Got it sort of welded together, but very inconsistent penetration on the back of the weld. Did all crush just about flat in the Wheel.

What I'm not really seeing though is an actual puddle, or much if any 'flare' from the flux. It's more a sagging of the surface.

From what I've seen in a couple of videos by the experts, the flux seems very much more fluid when heated. Should I be seeing something more in terms of the flux?

At this stage to have a play, I've just grabbed locally available flux from one of the major welding suppliers.

Appreciate any guidance. Thanks.

Attachment 52939

Attachment 52940

Attachment 52941

Attachment 52942

crystallographic 05-25-2019 08:17 PM

Quote:

Originally Posted by skintkarter (Post 155949)
Well I finally had my head in the right space I thought to pick up the torch and try some O/A welding of aluminium.

Fluxed the top side of the join with the flux mixed to a thin paste with Isopropyl Alcohol. Tacked the coupons together just with the torch, cleaned and tapped flat on the stump.

Re-cleaned everything and re fluxed (just the top surface of the join). Obviously some tension in the panel, as the start of the weld began to crack behind me - and perhaps not enough pre-heat as with tig cracking. Possible issue also with starting the weld in front of the first tack.

Material is 1.6mm 5005 and filler rod is a sliver cut from the edge of the sheet.

Got it sort of welded together, but very inconsistent penetration on the back of the weld. Did all crush just about flat in the Wheel.

What I'm not really seeing though is an actual puddle, or much if any 'flare' from the flux. It's more a sagging of the surface.

From what I've seen in a couple of videos by the experts, the flux seems very much more fluid when heated. Should I be seeing something more in terms of the flux?

At this stage to have a play, I've just grabbed locally available flux from one of the major welding suppliers.

Appreciate any guidance. Thanks.

Attachment 52939

Attachment 52940

Attachment 52941

Attachment 52942


Okay, good start.
Now, keeping all elements the same, mix a fresh batch of flux with clean spring water - like a bottle from the store. (Not distilled.) (Not tap water.)

skintkarter 05-25-2019 09:18 PM

Quote:

Originally Posted by crystallographic (Post 155950)
Okay, good start.
Now, keeping all elements the same, mix a fresh batch of flux with clean spring water - like a bottle from the store. (Not distilled.) (Not tap water.)

Many thanks Kent. I've got some fancy dinner party carbonated spring water here, so will give that at try and if not just head down to the gas station and pick up some still water. Appreciate the prompt help from the master!

crystallographic 05-25-2019 10:13 PM

Quote:

Originally Posted by skintkarter (Post 155952)
Many thanks Kent. I've got some fancy dinner party carbonated spring water here, so will give that at try and if not just head down to the gas station and pick up some still water. Appreciate the prompt help from the master!


Carbonation makes no difference - from many tests I've done across the US.
(Pellegrino/Gerolsteiner also make good espresso.)

skintkarter 05-26-2019 02:05 AM

2 Attachment(s)
Quote:

Originally Posted by crystallographic (Post 155953)
Carbonation makes no difference - from many tests I've done across the US.
(Pellegrino/Gerolsteiner also make good espresso.)

Thanks Kent. A little better, but I need to play with the consistency of the flux to get proper coverage without it breaking the film and balling up - couple of attempts with it too thin I think.

Attempt below is with carbonated spring water, top and bottom of the coupon fluxed, as well as the rod. Only get brief flashes of molten metal as I scratch the puddle with the filler rod. Some penetration, but a bit inconsistent and too much filler on the top.

Think I need a bit more heat, move a little faster and perhaps some better flux.

Attachment 52945

Attachment 52946

Poor workman always blames the tools of course!

I've just ordered some of your super duper flux and the DVD Kent.

Hopefully it will be just like Tom and Jerry and the Rachmaninoff piano concerto deal. :)

neilb 05-26-2019 04:11 AM

you'll get there richard, persistence pays off

skintkarter 05-26-2019 05:29 AM

Quote:

Originally Posted by neilb (Post 155958)
you'll get there richard, persistence pays off

Bloody Yorkshiremen... :)

Thanks Neil. Reading a bit more, I think I need to move up from a CIG #8 and get more heat with a softer flame. I'll have a look at the US/UK sizing charts. I'm not wearing jandals, so what can possibly go wrong :)

crystallographic 05-26-2019 02:43 PM

Quote:

Originally Posted by skintkarter (Post 155956)
Thanks Kent. A little better, but I need to play with the consistency of the flux to get proper coverage without it breaking the film and balling up - couple of attempts with it too thin I think.

Attempt below is with carbonated spring water, top and bottom of the coupon fluxed, as well as the rod. Only get brief flashes of molten metal as I scratch the puddle with the filler rod. Some penetration, but a bit inconsistent and too much filler on the top.

Think I need a bit more heat, move a little faster and perhaps some better flux.

Attachment 52945

Attachment 52946

Poor workman always blames the tools of course!

I've just ordered some of your super duper flux and the DVD Kent.

Hopefully it will be just like Tom and Jerry and the Rachmaninoff piano concerto deal. :)


Set the flame "fat" and just below a growl. Metal thickness = tip orifice.
Cone length = heat, so set cone length to 2 or 3 metal thicknesses.

Half a cone of feather, for the excess acet. This can vary as part of your own "chemisty adjustment."

And Thicken the flux - creamy not milky.
Everything is measurable with this.

skintkarter 05-26-2019 07:17 PM

Quote:

Originally Posted by crystallographic (Post 155967)
Set the flame "fat" and just below a growl. Metal thickness = tip orifice.
Cone length = heat, so set cone length to 2 or 3 metal thicknesses.

Half a cone of feather, for the excess acet. This can vary as part of your own "chemisty adjustment."

And Thicken the flux - creamy not milky.
Everything is measurable with this.

Thanks Kent. I've just bought some different flux to play with whilst I wait for yours to arrive. Have also come to the conclusion that I don't have enough heat. Have been using an #8 tip (0.8mm) so by your recommendations Kent, I need to be up around a #12 or even a #16. for the 16swg I'm trying to glue. I'll make sure I have appropriate footwear on and have another play this afternoon.

fciron 05-26-2019 11:33 PM

In my relatively recent experience you don't see a nice shiny puddle the way you do with steel. So, don't worry about that.

The expensive blue filters do make it easier to see what's going on. I thought I was seeing just fine through my green shade five until I tried one of the aluminum welding filters and it's a huge difference. You'll see the puddle then.

I agree thevlack of penetration sounds like not enough heat I tilt the torch more when welding aluminum than for steel, because that's what I was taught and it seems to work. I know that the higher conductivity of aluminum means it often needs more heat than the low temperatures involved suggest. I think aiming the flame more in the direction of travel spreads the heat over a larger area, countering the conductive loss without burning through right under the torch. (Hopefully. ;-) )


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