[cj737]

Looking for some recommendations on using a Helium mix to TIG some 1/4" and 3/8" aluminum. Using a Dynasty 200 with a 17 air cooled torch. My understanding is that the % of Helium will allow me to run lower amps with equal or better heat. But, do you recommend 90/10 or 80/20 for reliable results? This project is purely for myself, nothing structural that lives depends upon, and certainly no certification tests. Do you change the cup size as a result of choosing to use Helium, or stick with your standard cup choice?

Any recommendation about how much CFH with either mix too would be appreciated. And of course, roughly what percentage of amperage drop at the unit would I likely see as a result of the mix, 5%, 10%, 20%?

So I'm mostly looking for guidelines because I understand "actual mileage will vary" but know many of you will have some great insight.

Thanks!

[LtBadd]

If I remember the LWS sells mixed Ar/He at 75/25 and 50/50, not sure about other % but someone else will know.

Below 25% helium I don't think you'll see much difference, translating % helium to amps would be difficult I believe you'll just have to try the mix and see.

[Olivero]

IF this is just for you, just bevel the joints on either side or both sides and weld em up.

I have a Dynasty 200 I have done plenty of 3/16" and 1/4" with it, 80 or 60 grit flap disc and off you go.

[Oscar]

You definitely need a decent amount of helium to get a good benefit.

I found this picture online, don't know how accurate it is.

[Olivero]

Normally, the part of me that's in the gutter would say something about this, but I am not going to.

I would honestly just do it AC if it was me, I have done it and it takes some beveling but I can't even imagine the amount of heat you would need to do it DC.

[LtBadd]

Normally, the part of me that's in the gutter would say something about this, but I am not going to.

I would honestly just do it AC if it was me, I have done it and it takes some beveling but I can't even imagine the amount of heat you would need to do it DC.

I reread the OP, don't see any mention of welding this DC...? Or AC

[Olivero]

Normally, the part of me that's in the gutter would say something about this, but I am not going to.

I would honestly just do it AC if it was me, I have done it and it takes some beveling but I can't even imagine the amount of heat you would need to do it DC.

I reread the OP, don't see any mention of welding this DC...? Or AC

Lol, my bad, I thought I was on a different post.

[cj737]

IF this is just for you, just bevel the joints on either side or both sides and weld em up.

I have a Dynasty 200 I have done plenty of 3/16" and 1/4" with it, 80 or 60 grit flap disc and off you go.

Thanks, I know I can do it without using Helium. The goal is to do it with less than 150 amps on AC if that's possible with a Helium mix. I know I can run my 17 air cooled torch above that, I know the Dynasty will do it, I'm exploring alternatives to straight high amperage on AC.

[Otto Nobedder]

IF this is just for you, just bevel the joints on either side or both sides and weld em up.

I have a Dynasty 200 I have done plenty of 3/16" and 1/4" with it, 80 or 60 grit flap disc and off you go.

Thanks, I know I can do it without using Helium. The goal is to do it with less than 150 amps on AC if that's possible with a Helium mix. I know I can run my 17 air cooled torch above that, I know the Dynasty will do it, I'm exploring alternatives to straight high amperage on AC.

50/50 Helium/Argon on 1/4" at 150A will work quite well on very clean metal. If you can't go above 150 briefly when you start, pre-heat the metal for an easier start.

Steve S