Miller EconoTig experiences

They work. I owned one for 5 year, and did a lot of work with it.
You have to do some tricks to get up to 1/4" aluminum on one though.
I used a Argon/Helium mix gas to boost my heat, and rigged up a water cooled torch.
Air cooled torches suck for heavy aluminum.
I eventually upgraded to a Syncrowave 250 since I kept tripping the overload breaker on it on aluminum.
Figure 20 ga to 3/16" as the real range of the machine.
How much are they asking for it? Is it new?

It's new, listed on ebay, but from a local dealer.
They are asking $1174.59 for it. I already have a mixed gas bottle, which I can use for tiggin' steel, and I would have to get an argon bottle.
I would like to be able to do so moto-cross parts, skid plates, etc., which I would expect to use 3/16's Al.
It's mainly because I have a house project that I got the wifes approval to buy a new welder, and want to get something I can do Al with also.
Several posts on the miller forums say step up to the Syncrowave 180, which is about $300 more, but it ends up being 2x what I said I was going to spend on a welder.....
Thanks, Rod
Ernie Leimkuhler wrote:

If your mix gas is Argon/CO2, then no you can't use it for TIG.
Only Argon, Helium or a mix of the 2.
They work, but they have limitations. I would check eBay for used ones. They go for $700 - $850 used.

Ernie, would the maxstar 150stl work for him? I know it's DC only but for what he wants to weld in alum I would think it work. I'm thinking that the maxstar is a bit nicer than the econotig because of portability, price, and performance, (at least that's what i'm reading) You have (or had) a maxstar 140 didn't you? (the maxstar 150 stl goes for around $1095. on ebay) walt

The problem is that the Maxstar 150's pass the gas through the power connector. This makes it very complicated to do DCEP aluminum TIG.

Ernie, I did a google search Pure Argon shield gas Aluminum
DCEP 3/32" Zirconium tungsten: Layed a very clean weld on 0.024" 5052 aluminum. Easy to control at 25 amps and very clean. Did I mention Clean. No excessive tungsten erosion
DCEP 1/8" Zirconium Tungsten: An almost textbook perfect weld on 1/8" 6061 T6 bar. Nice control , no problems at 60 amps. Very controllable.
so i was hoping that for the occational aluminum welding i was planning, the 150 stl would be decent. Did they change the gas flow on the 150 from the 140? thanks, walt

The 140 was made by Fronius in Austria. Miller had a lot of trouble getting replacement parts from Fronius to warranty the 140's.
The 140 had a gas line that went from the flow gauge to the torch. You gas was controlled by the valve on the torch. This made it very easy to run DCEP aluminum since all you did was swap your power connectors.
The 150 uses the same DINSE connectors, but the gas is fed through the machine. They have added a gas solenoid to the 150 so you don't need a torch with a gas valve. This means that to do DCEP aluminum you will have to split the gas and power from the Negative terminal on the machine. It can be done, it is just annoying. You will have to scrouge up some odd brass bits to do it.
The 150 is an improvement over the 140 as far as output and features, and it is made in the US. What I find most impressive about the 150 is Miller's gaurantee that you can run 1/8" 6010 and 7018 from 110 volt power. That is impressive.
The Maxstar 200's also have a solenoid for the gas, but the gas has it's own connector on the front of the machine. I much prefer this setup.

The 140 was made by Fronius in Austria. Thanks, see we read ALL your posts! :) walt

Yes. The 150 uses a 25mm flow-through DINS instead of separate lines for the power and gas. This would be on the (-) terminal. The positive terminal has a regular DINS connector i.e. no gas.
To run DCEP, you would need to get the Argon to the torch. I'm sure there is a way, but it is not a simple or cheap solution like it is on the 140.
Jeff Dantzler

I wonder how difficult it would be to replace the positive DINS connector on the front panel of the 150 with a flow - through type and tee it to the argon supply inside the machine?
--Winston

Getting inside an inverter to ADD something is not a task I would take on. There is precious little room to spare inside most inverters.
I would come up with an external solution.

Aaargh !!!
I bought a 140 way back in 2000 when I read your original post. So far, (Touch wood) it has never missed a beat. Did they turn out to be unreliable? If so, what was the common failure mode/parts?
Barry Lennox

Not unreliable, but Fronius was unable to meet Miller's rather strict requirements for replacement parts availablility.
They were great machines, and Fronius is the top inverter maker in Europe, so they are far from junk.
I only learned this last week.
The repair guys I know have both commented on how few 140's they have seen.