Mig Welding

[Trent Flemming]

Hey Gang,

I am about to purchase a Millermatic 211 and the salesman says there is little benefit in getting a Argon/Co2 bottle for shielding over the flux core wire. I have a cheap harbor freights mig welder and never had an opportunity weld with shielding gas.

Any thoughts?

The bottle full of gas is about $190.00 and refills are $30.00.

The salesman also says the non shielded wire will rust over time and a hobbyist will not use it quick enough to fight off the rust.

Trent

[Tom Veatch]

First, I'm not going to claim to be expert in any form of welding. I have a MillerMatic 180 and have done a little with flux core, and more with 25% CO2 gas. Enough with flux core to know that I'll choose flux-core over gas shielded only if wind conditions prevent use of the gas, or if my bottle is empty and I don't have time to get a refill. And under those cases I'd probably break out my Thunderbolt 235 stick welder.

Expert welders may have a different take on it, but in my inexperience, it's flux-core only when there's some reason I can't do gas. If there's some concern about the solid wire rusting up (I haven't seen that, BTW) buy the small 1# spools.

[Matt Meiser]

I'd buy the gas and use the solid wire. IIRC, the flux core stuff leaves a crust of flux on your welds that has to be cleaned off. Any residue left on the gas shielded welds comes off with a couple strokes of a wire brush. The wire is copper or ??? plated. I don't have a problem with rust at all. Then again we are in a different climate. I've just about used up a larger size spool of 0.035 which is all I've run in mine after about 3 years. I've got a small unopened spool of flux core and the same of 0.024. The latter probably would have been better on the 16ga stuff I just did but the 0.035 worked.

Not sure what size bottle you are looking at but I just did my first exchange on one of the bottles that's about 3.5-4' tall. I think it cost $25. I'm not sure I needed it but knew it was getting low and then I knocked something on the regulator and smashed the gauges So since I had to the welding store anyway I took the tank and exchanged it. The flowmeter type regulator I got seems to be a nice upgrade for about the same price as the gauge type if its not already included with your machine.

That looks like a nice machine BTW!

[Rick Davidson]

I have been welding for many years off and on and am no professional, but I would also go with the gas and solid wire.

[Eric DeSilva]

The salesman also says the non shielded wire will rust over time and a hobbyist will not use it quick enough to fight off the rust.

As a rank amateur with that machine, I go through wire pretty darn quick. Mainly on the theory that if you can't make a good small weld, make a long, long bad weld. My stuff is ugly, but it holds.

[Anthony Anderson]

I have used a mig welder, and other types (oxy-acetylene, arc, and also plasma cutting), for more than twenty years. I currently own a Millermatic 33 (220 volt/150/60%duty cycle), and a Hobart 145 (120 volt machine). I can say with all certainty, that you want the Argon/CO2 mix.

Not sure why the guy at the welder's supply tried to direct you to the flux core. If you have used flux core in the past, you will not believe the difference in weld quality. Smoothness of weld, both from the machine, and burn-in, hot spatter will not be going everywhere (especially places where you don't want it to go, and it always seems to happen). Welding with shielding gas will make you a better welder, at least it will seem like it.

If you happen to be welding in windy conditions, set up a wind shield/break, and that will take care of your problem. You can always turn up your gas a little, and that will help in mildly windy conditions.

You will enjoy your welder. Hobart is also a good machine, and I believe, are now the same parent company. But do get the bottle of shielding gas.

Bill

[Scott T Smith]

I have used a mig welder, and other types (oxy-acetylene, arc, and also plasma cutting), for more than twenty years. I currently own a Millermatic 33 (220 volt/150/60%duty cycle), and a Hobart 145 (120 volt machine). I can say with all certainty, that you want the Argon/CO2 mix.

Not sure why the guy at the welder's supply tried to direct you to the flux core. If you have used flux core in the past, you will not believe the difference in weld quality. Smoothness of weld, both from the machine, and burn-in, hot spatter will not be going everywhere (especially places where you don't want it to go, and it always seems to happen). Welding with shielding gas will make you a better welder, at least it will seem like it.

If you happen to be welding in windy conditions, set up a wind shield/break, and that will take care of your problem. You can always turn up your gas a little, and that will help in mildly windy conditions.

You will enjoy your welder. Hobart is also a good machine, and I believe, are now the same parent company. But do get the bottle of shielding gas.

Bill

+1 on Bill's advice. I'm a 30+ year welder and own a full complement of welding equipment, including mig, tig, diesel engine driven, etc.

Unless you will be welding extensively outdoors, gas shielded is a much better option.

I remove my wire spools when I'm not using them and bag them up - no problem with rust.

[Trent Flemming]

Sawmillcreek members are the best. Thanks for the quick help.
Argon/CO2 it will be.

Trent

[David G Baker]

Trent,
You have made a wise choice and have received great advice.

[Al Willits]

Gas always for me, never like the properties of flux core, personal choice though.
No rust problems, leave new spools in plastic bags they come in and the spools that sits on the wire feed, haven't have any rust problems in all the years I've used it.
Could be a climate thing too. ?

Initial cost on tanks is high but a tank goes a long way, learn to adjust pressure and it can go even further.
Lots of welding variables can be made just though gas pressure/amount

Have fun
Al

[harry strasil]

I made my living Blacksmithing, welding and Machinist for 55 years. I had flux cored capability, but only used it outside. Millermatic 200 machine, copper coated, Hobart HB28 solid wire and CO2 is all I ever used, and you can get the small bottles that are used for soft drink machines, CO2 is realitively cheap, and easy to get. And the Hobart wire is the best on the market, even for slightly rusty metal. FWIW

[John Pratt]

I too recommend the gas. If you don't think you will be using your welder often or don't have the storage for large gas bottles, check out the Millermatic Passport Plus. It is an entirely self contained system that allows flux core wire or shielding. It comes with a small bottle in the "pelican" case but allow for the addition of larger bottles if needed. I have four different welders (Lincoln, Miller, Hobart) and I love the versatility and portability of this model.

[Dave Johnson29]

Millermatic 211 and the salesman says there is little benefit in getting a Argon/Co2 bottle for shielding over the flux core wire.

Trent, Now there's a salesman who does not know what he is talking about. I'd be wary of other claims he may make based on that statement.

Gas and flux is like day and night. Go gas unless it is totally impossible because of wind etc. I keep a small reel of flux cored in case I need it, but in 4 years it has not be on the machine.

[Craig Summers]

I used to be a part owner of a construction welding company, 40 or so employees. We had 7 gas migs (GMAW) for the shop, and only two flux core machines (FCAW).

The tiny Hobart flux core (sim to the OP's description) was for field welding of expanded metal to sheet metal studs for skiff rooms or higher security walls (under the drywall). We bought it for that work, otherwise it gathered alot of dust. Welding needs heat, and the smaller flux core doesnt have it. And the FCAW splatters more, something we didnt want for most welding. They also have a lower duty cycle, meaning you should only weld for x% of the hour (eg 10% duty cycle = 60 x .10= 6 minutes weld per hour) you are working, the machine needs the other % of time to cool back down (eg 10% duty cycle = 60 x .90= 54 minutes of cool down per hour). If you don't let the machine cool down, it will reduce the usefulness and life of the machine, and there should be UL approved thermal shutdowns in your machine.

The other flux core was the Lincoln .045 InnerShield, a structural grade FCAW machine that welded faster (lbs per hour) than the 7018/7024 3/16 rod for steel I-Beams and columns. Serious production and smoke when using that machine.