gas mix

[kd4gij]

What is the best gas mix for mig hobby welding steel

 

[bfd]

I have good luck with co2 bill

 

[f350ca]

Argon / CO2 is the common mix, I use a try mix of Argon / CO2 / Oxygen. Forget the percentage of oxygen 3 or 5 . Gives a much hotter weld with better penetration for heavy sections but impossible to weld less than about 10 guage with it, way too hot.

Greg

 

[gr8legs]

"Best" is a relative term;

Best price/performance would be straight CO2 - but it leaves a lot of spatter - so you need Pam or other vegetable oil to make the spatter easier to remove.

Best quality of weldment may be a toss up between Argon/CO2 and Tri-Mix (Ar/CO2/O2) but the gas mixes are much more expensive per inch of weld than the straight CO2.

YMMV

Stu

 

[Terry Worm]

I have had very good luck with C25 and have a strong preference for it. It is 25% CO2, 75% Argon. It can be used for carbon steel, stainless steel, and coated steels. Spatter drives me nuts, thus my distaste for straight CO2.

 

[kd4gij]

I have been searching around the web and I need to find out just what the welder is I may be getting. It is an old miller But it is up on a high shelf and facing the wall.

Based on pic from the web it may be a millermatic 200. Looks like this from what I can see.

 

[Hukshawn]

I use 85% argon and 15% co2. Little more expensive than 75/25 but a little less splatter. It’s a fine balance.

 

[Ulma Doctor]

75/25 for steel
tri-mix for stainless

 

[roadie33]

I have been searching around the web and I need to find out just what the welder is I may be getting. It is an old miller But it is up on a high shelf and facing the wall.

Based on pic from the web it may be a millermatic 200. Looks like this from what I can see.
View attachment 249963

That looks just like mine. Mine is a 200 w/SKP. I picked it up at a School Auction for $150. It came with a Bernard gun. Only had to do a few minor things to it and it welds great. I use C25 on mine. Stripped it down, taped off the emblems and primered and painted it, Rustoleum Safety Blue. Very close to stock color.

 

[Tony Wells]

Impossible to tell for sure, not being able to see the front panel, but from the back, it looks identical (like more than a few others I suspect) to my MillerMatic 35s. It has some unique features that are quite useful for thin work, but can be used for heavier materials as well. It's not fancy, other than the sheet metal features. You have to manually change taps on the transformer output to change the output, but the wire feed is enclosed, which helps it stay clean. Overall, I like the machine, but it's not my go-to MIG. That would be the Lincoln CV-300 with a piggyback LN-7 wirefeed. If you can pick that Miller for the right price, go get it. I've burned about 30 rolls of wire in mine and have no complaints.

And for gp welding, I normally use straight CO2. The little spatter doesn't usually bother me, but if it does I use Spattershield or hit it with a flapwheel.

 

[turnitupper]

My welder only goes down to about 35A and I had trouble butt welding steel less than 1mm using Ar 83 Co2 5 O2 mix. Tried pure Argon and have less trouble. Whack a roll of Silicone Bronze in and have almost no trouble except for the mig rollers dragging money out of my wallet!.
Have welded 12mm with the mixed gas 200A. 1.2mm wire in one pass, not pretty but strong???.
John.

 

[kd4gij]

That looks just like mine. Mine is a 200 w/SKP. I picked it up at a School Auction for $150. It came with a Bernard gun. Only had to do a few minor things to it and it welds great. I use C25 on mine. Stripped it down, taped off the emblems and primered and painted it, Rustoleum Safety Blue. Very close to stock color.

View attachment 249967

View attachment 249968

Does yours do stick weld also?

 

[682bear]

C25 works well for me on mild steel from 20 ga sheet to 1/2 inch thick...

-Bear

 

[roadie33]

Don't know if it would do stick weld, but it will weld with a gun.
I just need to find one that will fit it, that doesn't cost an arm and a leg.

 

[kd4gij]

I hope to get it down this weak and find out just what it is. If it works I know I will get it at a good price.

 

[gr8legs]

Regarding stick welding, generally a MIG machine is 'constant voltage' and what you need for stick welding is 'constant current' - so a MIG machine is not too good as a power supply for stick welding. A TIG machine can often be used for stick welding - both are 'constant current' processes.

There are 'multi-process' machines that can do mig / stick / tig all from one box and some of them do a good job with all processes - but some are compromises all around. I've had best results with 'purpose built' machines for each process - plus if one machine dies you have a backup.

Stu

 

[kd4gij]

Well I got it down and got a good look at it today. But didn't get a chance to try it out. Tomorrow hopefully. It is a millermatic 200 like Mike's but doesn't have the spot welder.

 

[kd4gij]

There is a spool gun with it now, spoolmatic 3, don't know if I will get that but a quick ? I know it is for aluminum wire but can it be used with steel wire also?

 

[Terry Worm]

No reason that they can't that I know of. Spool guns are often used where you need long leads in order to reach the work, but you can't push wire that far.

 

[kd4gij]

Well it is a millermatic 200 JE serial number made in 1984. The wire feeder isn't working. And the price is $000.00 Did I pay to much? AN I will pick it up 01/02 when I get back to work.
Does any one know where I can get a service manual for it? I found the owners manual online at miller.

 

[magicniner]

http://www.esabna.com/euweb/mig_handbook/592mig4_1.htm

Lots of anecdotal info above ignoring that straight CO2 gives best weld penetration for a given power for general steel fabrication and that Anti-Spatter Spray is specifically available to deal with the one small side issue involved ;-)
I follow the guide from the manufacturer of my welding equipment in the link above

 

[roadie33]

I had the same thing on mine and it was the fuse causing the wire not to feed.
It is a 5 amp standard fuse.
It is on the front right side by the work lamp indicator.

 

[kd4gij]

Thanks. When I get it home I will check that first thing.

 

[Weldit]

Argon / CO2 is the common mix, I use a try mix of Argon / CO2 / Oxygen. Forget the percentage of oxygen 3 or 5 . Gives a much hotter weld with better penetration for heavy sections but impossible to weld less than about 10 guage with it, way too hot.

Greg

We used the tri-mix gas in the structural shop until the last year when the new CWI switched over to argon/co2 90/10. At home I use C25 argon co2. I have a bottle of co2 that I pulled out when I exhausted the bottle of c25. CO2 is less expensive to buy but it does spatter more so be prepared that it does act a little differently than c25. C25 welds are "prettier". Watch CL for some deals. I bought 1 225cuft bottle and a 1 180cuft bottle for 150 bucks and exchanged them at the LWS. Great price!


Jim

 

[Ironken]

We used the tri-mix gas in the structural shop until the last year when the new CWI switched over to argon/co2 90/10. At home I use C25 argon co2. I have a bottle of co2 that I pulled out when I exhausted the bottle of c25. CO2 is less expensive to buy but it does spatter more so be prepared that it does act a little differently than c25. C25 welds are "prettier". Watch CL for some deals. I bought 1 225cuft bottle and a 1 180cuft bottle for 150 bucks and exchanged them at the LWS. Great price!


Jim

I'll betcha that we purchased cylinders from the same guy........over in Independance? I've got 4 from him off of CL here in KC.

 

[dlane]

I bought my bottles 30yrs ago in TX ( life time lease they called it ) over the years and moving they got switched with
Company lease bottles ,in this state they won’t exchange them, they want me to repurchase them.
Moral of story, if the ring under where the cap screws on has a company name embossed in it that is a lease bottle according to Airgas in California.

 

[firestopper]

75/25 for general steel MIG welding, 90/10 using pulse MIG on general steel and argon for most TIG and alum spool gun MIG.

 

[roadie33]

I'll betcha that we purchased cylinders from the same guy........over in Independance? I've got 4 from him off of CL here in KC.

I see his adds on CL also and was wondering how good the "Deals" were.
If they were actually clean bottles or re-purposed Lease bottles.
Currently I have 1 C25 and 1 Argon lease from Matheson.
I would rather "Own" them than pay a fee every year.

 

[Weldit]

I know the guy you're referring to on CL, but I didn't buy from him. I thought his prices were right about where Matheson is. I did buy them off of CL though but from a guy needing to make some money. Those deals don't come along everyday.

Also, we don't use pulse mig in the shop. We use metalcore wire with 90/10. Come to think of it I believe we also use it for dual shield as well.


Jim

 

[Downwindtracker2]

Here in Canada, bottle have to be tested every 10 years, even BBQ propane ones. Buying a "company" bottle avoids that. My argon is my own where as the mix , oxygen and acetylene are Air Liquide. Bottles have serial numbers and I've turned in a large oxygen that my son was given. I was hoping to swap it out for a small tri mix, chuckle.