2" Aluminum Weldment looking for advise on Equipment

[Portable Welder]

I have the Cobra Mig 260 Push Pull system which is from MK products,Its approximately a 2003 model.

I just quoted a big aluminum job to weld 2" thick aluminum plate together with several ribs to be welded under the plate that are 3/4" thick x 14" tall.

Ive been looking at the welder that OTC offers that does pulse mig but isn't a single phase machine, so now I've been looking at the miller.

Miller has the 350 MPA and the MM 350 pulse, I just wonder how they will stack up to the Cobra that I already have.

The fact that the miller machine puts out more power should help for cooking into the 2" aluminum plate where my 260 amp machine is going to require a ton of pre heat.

So who has used both and is there a big difference between the Cobra verses the Miller

And who has used the 2 millers, The 350 P verses the 350 MPA.

[Shade Tree Welder]

I moved your post to a new thread, hope you do not mind, but I think you
will get more mileage out of it separate from Lucky Jack the Thief's push pull
thread...

[Shade Tree Welder]

Cannot answer you question directly. I have a MM350P and a 30A spoolgun
I did weld up some 3/4" aluminum plate and the machine did not even
break a sweat. I was reparing cracks and has to grind our a deep V to
get good penetration. Did in 3 passes. I have not every had the chance
to run a push pull gun. The vast majority of my business was steel, I saw
more cast iron than aluminum.

[platypus20]

Originally Posted by Shade Tree Welder

...... from Lucky Jack the Thief's push pull
thread...

Say What??

[monckywrench]

It wouldn't hurt to call Miller tech support and see what they recommend for the job.

Please pics of the job when done.

[LW Hiway]

In your shoes I would most certainly get on the phone with the technical people at Miller.

Excellant advice Dr. Bob. I've never seen the big 2, Miller or Lincoln, not jump through hoops when it came to helping with the spec'ing in of new equipment.

FWIW, in Salina, the Lincoln dealor was at the plant several times a week and sometimes would stand shoulder to shoulder when we were setting up an new production type machine with their welders being part of it. Automated beam welding monstrosities etc. and the like.

Give em a shout.

I would not hesitate doing something like this with my MM350P. It could handle it with ease. One of these days I'd like to push the thing to the point to make that awful quiet cooling fan actually turn on and run.

[Portable Welder]

Pyro J, The Aluma Power 350 MPA is actual single or 3 phase machine.

It also comes with a price tag of $ 9,050.00

It would be nice if Miller had a shop set up to go and try there products to see which one is best for my application.

I've been to half a dozen Miller road shows over the years but they dont always have everything set up.

[LKeithR]

Originally Posted by Portable Welder

...I just quoted a big aluminum job to weld 2" thick aluminum plate together with several ribs to be welded under the plate that are 3/4" thick x 14" tall.

You quoted this job without knowing for sure how you're going to weld it? Hope things work out for you.

We've never welded anything that thick but I can tell you for sure that 2" material is going to be a huge heat sink, especially if you're working with larger pieces. Your 2" material is more than 2-1/2 times as thick as 3/4" and I'm willing to bet there is some incremental increase in the amount of heat you're going to need to weld it.

Another thing to consider is if this is a big job and you're going to be welding continuously at or close to maximum amperage you'll need a good high duty cycle. Can't help with the actual welder selection; all we have is a 250 amp Lincoln...

[allessence]

I have never used a Miller Mig for any production..

I have ran Yeti which is a 500amp machine with 380amp continuous..

I don't have a push/pull gun but if the job is going to pay well enough adding that to the deal would be a no brainer..

The OTC looks like nice machine.. You are gonna be generating some serious heat.. Hope you have a water cooled gun and the heat reflective gloves..

[FabberMcGee]

It could help to use Helium for a shield instead of Argon to make your fire hotter. I've done that many times with tig on heavy aluminum castings and it seems like I used it with mig a time or two, but that was long, long ago and the memory circuits are in need of repair. Worth a try.