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Up Topic Welding Industry / Processes / 1/16" Aluminum Fillet - Water/Vacuum Pressure Boundry
- - By brownl21 (*) Date 12-17-2019 15:53 Edited 12-17-2019 15:59
Any suggestions on a process to complete this joint?  We are trying to GTAW it and not having real good luck.  The configuration makes it difficult to get the torch angle right and even if that wasn't an issue the fillet can't be larger than 1/16" or it interferes with next assembly step.  I attached a section view.  Thickness is .040" at indicated weld joint ans is about a 5.5" diameter.
Parent - - By 803056 (*****) Date 12-17-2019 16:57
Looks like you have a fillet weld between item 1 and 2 that is inaccessible.

Why are you specifying fillet welds that are larger than the thickness of the base metal?

Back to the drawing board!

Al
Parent - - By brownl21 (*) Date 12-17-2019 17:40
Item 6 isn't in place yet when they want us to do that weld.  I agree that design needs to be changed but I'm being asked to find a way to weld it as it is designed now.  I'm just trying to make a good faith effort to do that.
Parent - By 803056 (*****) Date 12-17-2019 20:24
Good luck. A sows ear is a sows ear no matter what you call it.

Al
Parent - By TimGary (****) Date 12-18-2019 12:41
Brazing?
Parent - - By jwright650 (*****) Date 12-18-2019 13:16
I was hoping Lawrence would have chimed in by now. He has some experience with welding small fillets with GTAW on thin aluminum. When I purchased a cheap Tig machine with high freq features several years ago, I tried welding a drink can back together and Lawrence was telling me that it was possible, and he posted some pictures of where it was done. I wasn't successful, even with the machine down on the lowest settings when I lit the arc, it blew a hole through the material. I suppose the initial start up amperage was what was getting me and there wasn't any way to turn that down enough. Micro welding is what I call welding that really thin stuff.
Parent - - By Lawrence (*****) Date 12-18-2019 15:00
Attempting a 1/16” fillet with manual GTAW in a joint with poor access?

That’s bad design engineering...

But beating up the poor original poster for it doesn’t really get us anywhere.  Besides, that’s what Al’s for.

The drawings help make clear the difficulty of what you’re  up against, but if there is an answer at all for this, you will probably find it on the shop floor... 

Go as the welders if they can bail you out.
Parent - By brownl21 (*) Date 12-18-2019 16:07
Ha Ha, thanks.  I am the welder.  I think we can weld it, it's just that the fillet will end up being too big.  I think we are just going to end up welding it and then machining it down so the next piece will fit in.  I am expecting that after the machining op there's a good chance it will leak though.  I don't know what else to try and if we can't get it leak tight then they will be forced to redesign it.  I just was curious if there was another process besides GTAW that might get better results before we try to weld it manually.  I know essentially nothing about ebeam, laser, plasma, etc. and wanted to reach out to vendors that do that, but there doesn't seem to be organizational support for that.  Didn't know if anything like that would be feasible.  I gave them my opinion and voiced my concerns so I think we'll just go for it and see what happens.  Thanks.
Parent - - By 803056 (*****) Date 12-18-2019 18:11
Lawrence, where did I beat up the poster? I said the weld detail is bad. "A sow's ear is a sow's ear regardless of what you call it" is hardly a shot at the poster.

Why put the onus on the welder? Redesign the assembly to provide proper access.

Al
Parent - By Lawrence (*****) Date 12-18-2019 21:21
Hi Al....

I wasn’t shooting at you (this time)   I just invoked your name for fun...

I couldn’t help saying I didn’t like the design.... even though saying it isn’t particularly helpful :)
Parent - - By Lawrence (*****) Date 12-18-2019 21:36
Ok... now I have offended Al and contributed zero....

Time to repent

GMAWP with a robot?

GMAWP with custom heat sink fixturing?

GTAW with a badass asymmetric waveform and a equally badass heat sink.

Aluminum fillets are “puffy” compared to steel...  that’s just something the Engineer should know and consider....  typically the larger aluminum fillet is taken En passant because the weld often reduced the mechanicals in the base metal so the puffy weld gets the strength required.

Hot and fast gets the best seal, and GMAWP is the fastest you can go without spending millions.

Are you making thousands of this thing?  Just a few?     That has some bearing on what might be done for a solution.

If it’s cool to machine?   Why not look at a custom GMAW nozzle that will be easy to keep in the joint and blast away!
Parent - - By 803056 (*****) Date 12-19-2019 13:23
As long as you are aware that you damaged my self-esteem and scarred my psyche, I can go on with day to day tasks.

Merry Christmas Buckaroo. BFF?

Al
Parent - By welderbrent (*****) Date 12-19-2019 20:40
LOL
Parent - - By jwright650 (*****) Date 12-19-2019 20:50
Oh man, the mental image of Al with his suspenders in bunch has scarred my psyche. :eek:

Merry Christmas Buckaroos!
Parent - By 803056 (*****) Date 12-20-2019 00:47
:confused:

Al
Up Topic Welding Industry / Processes / 1/16" Aluminum Fillet - Water/Vacuum Pressure Boundry

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