View Full Version : Gas question

08-11-2011, 12:16 AM
So I have the miller spool gun for my miller 140 auto set. I have a tank of argon, but what should I set the gas at? There is no setting any where telling me what cfm to put it at?

08-11-2011, 12:22 AM
Its been a little while since I migged anything, but I think 15-20-25 cfh. You might need more if theres any breeze at all, or any other conditions like that. This link might help (but no promises) :


Bob the Welder
08-11-2011, 12:23 AM
If it's straight argon, better set it in the back of your truck and take it to your LWS and trade it for some 90/10 or CO2 or some 75/25. You want a gas that's usable for mig welding. 100% argon ain't it.

08-11-2011, 12:31 AM
"The most common shielding gas for MIG welding aluminum is 100 % argon. Flow rates of 20 to 30 CFH (cubic feet per hour) are acceptable." -Miller's Website

Dont think so, Bob... Hes welding aluminum, with a spool gun.

08-11-2011, 12:31 AM
Bob since he has a spoolgun, I think he wants to do alum mig. if so 100% argon is correct for that use. 100% argon is only wrong if he wants to weld steel with mig.

Bob the Welder
08-11-2011, 01:09 AM
You are right. Didn't catch the spool part.:blush2: Must be some pretty thin aluminum though.

randy o
08-14-2011, 01:05 AM
100% argon@35 to 40 cfm and you will be fine.Hope this helps.

08-14-2011, 01:34 AM
35-40 CFM. Really.....

Even 35-40 CFH will probably blow out what little arc that machine produces.:laugh:

Some people don't have a clue what they're talking about.

Where the he11 are these posters coming from???? Must be migrating over from the Chi-Com supported forums.

08-14-2011, 01:48 PM
Thanks guys Im trying some of the settings you guys recommended. 20 seems to work pretty well.. going to continue to mess with it

08-14-2011, 02:32 PM
100% argon@35 to 40 cfm and you will be fine.Hope this helps.

Whoa!! Your gas supplier must love you randy o.

08-14-2011, 05:13 PM
This is the result I got @ 20. Looks okay to me, First time I have really tried the aluminum with the mig.

http://a2.sphotos.ak.fbcdn.net/hphotos-ak-ash4/291750_10150258601161493_674141492_7868077_4976283 _n.jpg

08-15-2011, 12:04 AM
In Australia we use metric,ie l/m

Tig 7-14 Im in a factory I use about 7 on Stainless and 8 on Ally
Mig 10-20, Ally I use about 10-11 a mate of mine who is vastly more experienced than me swears by 18...I don't seem to see any difference.I only ever do Ally , no Steel or Stainless in Mig , well very rarely.
All are for 100% Ar at Sydney type temp ranges.
Tried a bottle of 50/50 He Ar and found I needed to bump the flow up a bit .Gave up on the He as I didn't like the way it welded and truth be known I was trying to get my PT 185 Lincoln to do what I should have been doing on my TransTig 300.

Check your flow meter maybe its in metric?

08-15-2011, 12:09 AM
Switch to Helium argon 50/50 or 75/25 and you might be able to get those toes wetted in.