25% hellium 75% argon??

[Jitter]

Im using 25% hellium 75% argon for my alluminum welding...works great. Can I use the same gas for welding mild steel? What is the best recomended set up for welding 3/16 square mild steel tubing? DYN 200DX thanks for your Help

[hankj]

I don't know about the Dynasty settings, but I'm sure soebody will step up.

As far as the gas, yes. It will weld hotter than 100% Ar due to the high heat conductivity of the Helium, but they are both inert gases, so there is no reaction with the weld metal.

Hank

[ASKANDY]

Jitter,
With that gas I'd say set the machine for DC and run the amps at around 160-170. That gas will run hotter and you may have to back off the foot pedal some or set the amps lower. Same tungsten just resharpen to do the steel and run the gas around 22-25 for that HE/Ar mix. I assume you are running the stock air cooled torch and not a gas lens??

Andy

[Jitter]

Im running a water cooled #9 weldco torch with a gas lense...is that not good?? Or is that ok??

[HAWK]

Jitter,

You may have to turn the flow up another 5 or 10 CFH depending on your tungsten stick out. I weld a lot of steel with 75% helium/25% argon. Yes, just the opposite mix you are using. It really gets hot and you have to pay attention and travel much faster. Good luck.

If you want to play some, then put the DX on AC at 97%EN balance, 110HZ, around 110 amps to start and give some 1/8 steel a try. Play with your EN balance from 90-99% and see what you think. Crazy? Try it. I have some clients that demand that process with some variation, but can't give all the secrets in a day...They took to long to learn.

[Jitter]

HAWK..thanks for the scoop....I will try that on my steel work....does it clean it better?? How much better does the DYN200 work when welding 1/4 ALU filet using the 75hel- 25arg?

[HAWK]

Jitter,

I have welded 1/4" steel with 100% argon, 50%argon/50%helium, and 75%helium/25% argon. The 75% helium /25%agon mix will do it easy once the puddle is established. It still takes a little time the get the puddle. It is considerable faster than the 50/50 ar/he mix. However, it is considerably more expensive to buy helium. The procedure using AC GTAW with a he/ar mix for steel is not well documented. I am not recommending you use this for anything other than fun and experimentation. DSEMAN and I have had this conversation before. I wonder if he has stumbled on any negative regarding this procedure?

[ASKANDY]

Jitter,
Your set up is great. With the gas lens you could drop your gas rates a little. Try around 20 first and see how that goes.

Andy

[Canuck]

I am getting an almost full bottle of 75%he/25%ar for free from a friend and would like to know what I should expect. Will there just be more heat or will I get a change in the arc? If si what can I do to make up for it? Thanks KB

[HAWK]

Canuck,

The 75% helium added to your shield will increase the heat input and widen the arc cone. If you can increase the arc frequency, using machines like the Aerowave and Dynasty, the arc cone will tighten up. The Sync 180 has no such adjustment so your puddle will be wider than normal. Let us know what you think.

BTW: FREE IS GOOD! I pay $33 per fill for the 300CF bottles which is very reasonable.

[Jitter]

HAWK......good scoop on the AC welding on mild steel....I like it better than welding DC on mild steel. Seems to be cleaner and better control. thanks for the tip!!!

[HAWK]

Jitter,

I am glad you tried it. I have mentioned it to a few people and posted here a time or two under different posts. You are the first to comment on having tried it. I found this procedure mentioned briefly in the Miller GTAW Handbook regarding the advanced square wave arc with AC and argon for material up to 1/8". However, I recall no specifics such as balance, frequency, etc.

The info I have given you is from my own trials and errors. I recently welded a "U" grove in a 3/4" steel plate running AC, 110HZ, 95% EN, ER80S-6 filler rod, 75% helium/25%argon, and 200+ amps. I don't really know the amperage as I set the machine at 300 and ran "blind" with the pedal. My guess is 240. I found the joint easy to weld. I made the joint by butting the 2 pieces of plate together and gouging the "U" groove with a few passes of a 1/4" carbon

[Blown S-10]

HAWK

why would you tig 3/4" ? seems to me smaw would be the way to go

could i use your ac on steel thing with straight argon ?

[arcdawg]

what does this do to the life of the torch..........since you are running so much hotter ?

i take it this is a water cooled only ???

dawg

[dyn88]

tig plate for appearance I would guess huh hawk. I have also found the high He mix is louder than Ar.