[Water-man]

Hi All,

I am Mark from The Netherlands and I am new here

I try to get nice shiny welds with aluminum tig welding.
But sometimes I succeed and sometimes I don't

I can't figure out what's causing this and need your help

The machine I have is a Rowac 201 ac/dc pulse and have tried all possible things.

For a budweld I use 30A for 1mm (0.039 inch) and this seems to work well, sometimes I find 23A for 1mm works better.
Usually I grab 3mm (0.118 inch) or 4mm (0.158 inch) aluminum

For the tungsten I now use 2.4mm (0.95 inch) I have also tried 3.2mm (1.26 inch) but this 2.4 seems to work best.
Colors I have tried blue, purple, gold and get, the blue works best for me.

As a cup I have also tried everything, standard and also with gas lens, from size 4 to size 8, the number 8 glass cup with gas lens seems to work best

Gas I use 100% argon with a flow of 5-7 l/min (10.5 - 14.8 CFH)
preflow 2 sec and postflow 8 sec

No upslope and no downslope

I have tried frequency between 60 and 200 hrz where I think 60 or 120 works best

Filler metal we use Alg5 (Lincoln SuperGlaze) 2.4 mm (0.95 inch) and 3.2 mm (1.26 inch).

For this test piece of 4mm (0.158 inch) aluminum I used the following settings:
-Tungsten 2.4 blue (0.95 inch) 30 grade cut with a blunt
-Filler metal 3.2mm (1.26 inches)
-Gas 100% Argon 7L/m (14.8 CFH)
-Ampere 95A
- Frequency 60hz
-Ac balance 42% (my machine can be between 20 and 50)
-No pulse
-Post flow 8 sec
-Prefow 2 sec

With these same settings I have weld after weld the Eben sometimes a nice shiny weld and the other time a gray dull weld, can you tell me what I'm doing wrong?

[cj737]

Dull grey welds on aluminum are most often associated with the base metal becoming overheated. The amount of amps you are using is very low by my experience. This causes you to weld too slowly because you won’t get a puddle quickly enough.

Start with higher amps, get your puddle, then taper the heat by using a pedal or torch switch.

Another thing you can adjust is the AC Balance. The more time spent on the POS side of the arc the higher the cleaning action.

[tweake]

For a budweld I use 30A for 1mm (0.039 inch) and this seems to work well, sometimes I find 23A for 1mm works better.
Usually I grab 3mm (0.118 inch) or 4mm (0.158 inch) aluminum

For the tungsten I now use 2.4mm (0.95 inch) I have also tried 3.2mm (1.26 inch) but this 2.4 seems to work best.
Colors I have tried blue, purple, gold and get, the blue works best for me.

As a cup I have also tried everything, standard and also with gas lens, from size 4 to size 8, the number 8 glass cup with gas lens seems to work best

Gas I use 100% argon with a flow of 5-7 l/min (10.5 - 14.8 CFH)
preflow 2 sec and postflow 8 sec

No upslope and no downslope

I have tried frequency between 60 and 200 hrz where I think 60 or 120 works best

Filler metal we use Alg5 (Lincoln SuperGlaze) 2.4 mm (0.95 inch) and 3.2 mm (1.26 inch).

For this test piece of 4mm (0.158 inch) aluminum I used the following settings:
-Tungsten 2.4 blue (0.95 inch) 30 grade cut with a blunt
-Filler metal 3.2mm (1.26 inches)
-Gas 100% Argon 7L/m (14.8 CFH)
-Ampere 95A
- Frequency 60hz
-Ac balance 42% (my machine can be between 20 and 50)
-No pulse
-Post flow 8 sec
-Prefow 2 sec

With these same settings I have weld after weld the Eben sometimes a nice shiny weld and the other time a gray dull weld, can you tell me what I'm doing wrong?

main problem is amps to low. it varies a bit with machine etc but i'm in the range of 50 amps per 1mm, however i also control with foot pedal.
main thing is you need to have the puddle form in the first few seconds. if you have to wait for it, your amps are to low.
you will find you will have to move faster. travel speed is the key to not overheating the material. so run it really hot and move fast.

95amps for 4mm, way way to cold. try at least double that.
if you run decent amps 2.4mm tungsten going to be on a small side. i recommend 3.2mm. 2% lath is fine.
balance, i would start at 30%. 20% if its really new and clean, 40% if its some super dirty cast alloy. the lower the % the more heat goes into the weld.
5 cup, maybe a 6 (if using 3.2mm tungsten). no gas lens. you want the opposite of what you would do for stainless.
use downslope, you want the weld to cool slowly to help avoid crater cracking.
filler the 3.2mm is fine.

[Water-man]

Dull grey welds on aluminum are most often associated with the base metal becoming overheated. The amount of amps you are using is very low by my experience. This causes you to weld too slowly because you won’t get a puddle quickly enough.

Start with higher amps, get your puddle, then taper the heat by using a pedal or torch switch.

Another thing you can adjust is the AC Balance. The more time spent on the POS side of the arc the higher the cleaning action.

thanks ! I will try this

[Water-man]

For a budweld I use 30A for 1mm (0.039 inch) and this seems to work well, sometimes I find 23A for 1mm works better.
Usually I grab 3mm (0.118 inch) or 4mm (0.158 inch) aluminum

For the tungsten I now use 2.4mm (0.95 inch) I have also tried 3.2mm (1.26 inch) but this 2.4 seems to work best.
Colors I have tried blue, purple, gold and get, the blue works best for me.

As a cup I have also tried everything, standard and also with gas lens, from size 4 to size 8, the number 8 glass cup with gas lens seems to work best

Gas I use 100% argon with a flow of 5-7 l/min (10.5 - 14.8 CFH)
preflow 2 sec and postflow 8 sec

No upslope and no downslope

I have tried frequency between 60 and 200 hrz where I think 60 or 120 works best

Filler metal we use Alg5 (Lincoln SuperGlaze) 2.4 mm (0.95 inch) and 3.2 mm (1.26 inch).

For this test piece of 4mm (0.158 inch) aluminum I used the following settings:
-Tungsten 2.4 blue (0.95 inch) 30 grade cut with a blunt
-Filler metal 3.2mm (1.26 inches)
-Gas 100% Argon 7L/m (14.8 CFH)
-Ampere 95A
- Frequency 60hz
-Ac balance 42% (my machine can be between 20 and 50)
-No pulse
-Post flow 8 sec
-Prefow 2 sec

With these same settings I have weld after weld the Eben sometimes a nice shiny weld and the other time a gray dull weld, can you tell me what I'm doing wrong?

main problem is amps to low. it varies a bit with machine etc but i'm in the range of 50 amps per 1mm, however i also control with foot pedal.
main thing is you need to have the puddle form in the first few seconds. if you have to wait for it, your amps are to low.
you will find you will have to move faster. travel speed is the key to not overheating the material. so run it really hot and move fast.

95amps for 4mm, way way to cold. try at least double that.
if you run decent amps 2.4mm tungsten going to be on a small side. i recommend 3.2mm. 2% lath is fine.
balance, i would start at 30%. 20% if its really new and clean, 40% if its some super dirty cast alloy. the lower the % the more heat goes into the weld.
5 cup, maybe a 6 (if using 3.2mm tungsten). no gas lens. you want the opposite of what you would do for stainless.
use downslope, you want the weld to cool slowly to help avoid crater cracking.
filler the 3.2mm is fine.

Thanks this is very useful info