MIG Aluminum help

[goinzer]

Okay, just got a Millermatic 211, and practiced a little bit with the spool mate 100 spool-gun,
Here are the results, any suggestions are appreciated

Overhead tee joint, argon, 035 4043 wire, 1/2 material for top plate, 1/2 or 1/4 for beam

[welder_one]

heat, heat, clean, heat, clean, and heat..... did i mention heat? turn that buggar up... i can not give you specifics with your set up cause i dont use it, but for 1/4 im running 25 to 26 volts and around 750 to 800 wfs.... this is .035 5356 on an xmt with xr-a push pull feeder

[sn0border88]

Without knowing what your settings are, id say you need to bump up your volts.

[BTD]

A MM211 might be a little undersized for 1/2" aluminum. I've got one (and the spoolgun too) and I think it's limited to about 1/4". Just my $0.02.

[Shadill]

Originally Posted by BTD

A MM211 might be a little undersized for 1/2" aluminum. I've got one (and the spoolgun too) and I think it's limited to about 1/4". Just my $0.02.

I agree, I also have the exact same setup, tried welding some 3/8 thick alum and it was at it's limit turned all the way up

[DesertRider33]

Plain and simple, you don't have a big enough mig to weld that thick aluminum, all the welds are too cold. Rent an XMT and Spoolmatic gun, or take it to a welding shop to have it welded.

[welder_one]

yup, like i said..... heat.... no offense, but people's most common thoughts when you say aluminum are pop cans and fryin pans.... thin metal = light equipment..... its so far from the truth, it hurts.... aluminum is a heat sink to begin with, therefore, you actually have to have heavier duty machinery than with the same thickness steel....

if ya want professional looking welds on that heavy aluminum, you have to have heavy professional equipment

[goinzer]

Ok, so a bigger machine is the only option, I am not buying equipment to pay someone else to weld, and it is important to me to learn how to do aluminum.
With that in mind, what about actual technique, this is basically my first try after running a few butt joints on flat plates, so any information beyond my lack of machine power would be appreciated.
can material this thick be done if I bevel an run more smaller passes? (I know I am trying to get the answer I want, this is the max thickness I will see, and taking the equipment elsewhere is not an option)
I find that I am still trying to run a puddle, and that seems to result in the "blobby" appearance though my next investment is a auto darkening helmet.
Based on my literature it looks this is 210 amps at whatever voltage the 211 does at that amperage.

[DesertRider33]

You're welding fillets there. Maybe it's just a shadow, but it looks like there's already a little curve at the shoulder of the tube, or whatever shape the lower piece of metal is, providing you with a bit of a 'bevel' in the fillet already. I don't see an opportunity for beveling the joints in the pics you showed. If there are some butt welds not shown, you can bevel them out, if you can get a grinder in there. Use a sandpaper wheel, not an abrasive disc.

You can try pre-heating along the joint with an oxy/acetylene or propane torch to help the machine get better fusion/penetration.

Most welding equipment rental shops rent XMT 304's and some rent spool guns and controllers too. Call and ask about it. Do you have a Red-D-Arc in your area?

[goinzer]

I checked that out and did see them, I will look for that setup, so will that sort of set up do this in one pass?

[Rojodiablo]

Originally Posted by goinzer

I checked that out and did see them, I will look for that setup, so will that sort of set up do this in one pass?

The Lincoln inverter wire feeder is like a 350P. That will do it. David R (absent mod) has one. He's cooked some big aluminum with it.

I say the inverter because it uses less power input to do the job. Transformer based 350A machine, you are looking at 100+ amps to power it up unless you have 3 phase.

[DesertRider33]

With an XMT 304, WC24 controller and Spoolmatic spool gun, running 3/64" (or better, 1/16") 4043, you should be able to run those joints in one pass.

[goinzer]

Ok, great information, I really appreciate it, so as long I am capable, the then so is the machine!