Aluminum welds

[monte55]

Some of my welds are shiny when some have a dull cast to them. Both welds look good. It seems like the weld I ran a little hotter and faster was shiny compared to a slower travel and lower heat. Welds are the same size. Is one weld better than the other? Tigging on aluminum. Amps, gas flow, are identical. Only difference was the foot pedal and speed.

[Bert]

I was told/taught if your weld is too hot (foot down too hard or too slow a speed), it'll look hazy. Want a shiny weld? Control the right heat more.
FusionKing: any advice?

[mikesparks]

I was told/taught if your weld is too hot (foot down too hard or too slow a speed), it'll look hazy. Want a shiny weld? Control the right heat more.
FusionKing: any advice?

i can get a shiny weld slow or fast. even if i use my foot to pusle weld it still turnes out shiny

[FusionKing]

Some of my welds are shiny when some have a dull cast to them. Both welds look good. It seems like the weld I ran a little hotter and faster was shiny compared to a slower travel and lower heat. Welds are the same size. Is one weld better than the other? Tigging on aluminum. Amps, gas flow, are identical. Only difference was the foot pedal and speed.

I was told/taught if your weld is too hot (foot down too hard or too slow a speed), it'll look hazy. Want a shiny weld? Control the right heat more.
FusionKing: any advice?

I think it has to do with the cleaning cycle of AC. Slower would mean more cleaning happening. I'm sure somebody like KB or SundownIII or Andy would give a much better explained answer tho and maybe a better reason.
I usually weld a little slow anyhow unless it's getting pretty close to lunch or dinner time
Hotter and faster and rythym make the best looking beads IMO and the HAZ would be smaller also.

[SundownIII]

Fusion King,

You got it. Run hot and run fast. No metalurgist, but suspect that it has something to do with prolonged heat changing the molecular structure of the aluminum.

I'm not in their league, but the best anodized aluminum tig welders (tower builders) I've worked with are running at about 195A without a foot or finger amp control. Just a simple on/off switch on the torch. High amps breaks up the anodizing, creates a great bead, and limits the heat transfer. With towers, the welds are painted after welding for protection but the weld bead is shiny. The paint, as I said, is only to prevent oxidation since it's physically impossible to reanodize an entire tower. Some tower builders use 4043 but the better ones use 5356 even though it will not be reanodized.

I've actually found, in most cases, that the Sync 250 is a little more forgiving of technique than the Dynasty's. Maybe it's just me. Good friend of mine (one of those experts) used to use a 250 and now has the Dynasty 300. Says he'd never go back. Guess I haven't used an inverter enough to fully take advantage of the freq. adjustments.

Hope this helps.

PS There was an excellent article written several years ago which circulated around the boards a few months back. In that article they interviewed several of the guys from Pipewelders (Fl Towerbuilders) who developed the bump techinique for welding anodized aluminum. (I posted a link at that time--do a search for anodized aluminum). The son of the owner of Pipewelders, Edison Irving, is a close friend of mine and taught me a lot about the technique.

KP and Engloid are the two tiggers on the board who I have been most impressed with. Both their welding and understanding of why certain things happen in the bead. ASKANDY is probably there too, but I haven't seen as much of his work. If any of those three make a comment regarding tig, you can take it as gospel.

Fusion King: Check out this link [url]http://archive.metalformingmagazine.com/1999/11/miller.pdf

[monte55]

One of the questions I had was...........is the shiny bead better than the dull
bead other than looks. Is one stronger, less brittle, etc.

[bvweld]

One of the questions I had was...........is the shiny bead better than the dull
bead other than looks. Is one stronger, less brittle, etc.

One possible reason for the differance in bead appearance may be with your faster travel speed allowing your bead to cool with the argon shielding it before it's exposed to air. Slower speeds will (heat soak) your base material and not allow as rapid of cooling while shielded. If contamination is not an issue the frosting should be only on the surface and should generally not make a strength difference. The shiney appearance as you know is what you should strive for when everything is done right. Good luck

[FusionKing]

I would go as far as to say that the PART with the shiney welds is a stronger PART because you kept more of the original temper...and that depends on the application.
Try not to think so much... OK

[Craig in Denver]

i can get a shiny weld slow or fast. even if i use my foot to pusle weld it still turnes out shiny

OK, Mike; ya don't get off that easy.

What machine, make-model; x-former or inverter?

And what filler; 4043, 5356; 1/16, 3/32?

Something works for you and WE want to know what it is!

[bvweld]

I would go as far as to say that the PART with the shiney welds is a stronger PART because you kept more of the original temper...and that depends on the application.
Try not to think so much... OK

Did some checking in the code books and could not find a weld defect classified under "dull or frosted appearance" For grins I called a friend of mine who is a CWI. If it is only a dull surface appearance it isn't considered a weld defect.