MIG welding aluminum, melting tips

[Debriefer]

Subject says most of my problem: I am trying to weld aluminum with my MIG welder, and the tips melt, within seconds of use. Clearly I am doing something very wrong.

I have tried holding it close (1/4" away, or far, up to 1"). Far seems better, but it still happens. I have also tried turning up the wire speed to prevent it from happening. I am using a dragging/pulling angle (not sure of proper term) of about 10 degrees, and I have the all-argon gas set to about 25CFH.

I am using 1/8" 6061 as a workpiece with 0.035" 5356 wire. I have a Miller 211 auto-set with the super expensive spool gun, so I don't think I can blame the equipment this time around.

Any ideas? This seems like a rookie mistake. I only have one tip left, so I'd like to make it count.

 

[Murphy4570]

Got the amps set too high?

 

[JayL]

I have a Millermatic 180 with a spool gun. Have not tried it yet on aluminum but would like to do so as soon as I get the Argon Gas. I would be very interested to know more about this tip burning issue too.

I hope the the Spoolmate 100 gun is up for the task. Looks cheesy to me compared to the Millermatic welder build itself ...

Subscribed.

 

[welder4956]

Check the drive roll tension and make sure it is not too loose. You want to tighten it just until you can hold the wire at the tip with your hand and it not slip when you pull the trigger. Too tight and it deforms the wire and hangs in the tip, which could also cause your problem. You may also need to drop the voltage setting slightly on the machine.

 

[koditten]

Make sure you haven't lost one of the power legs in you welder plug. This has happened to me twice. You will vaporize the tips if this happens.

 

[Heavy Metal Doctor]

I have no details in my head, but we also bought one of the spool guns to add on to and old miller 200 (or 210??) mig machine and a bottle of straight argon specifically to do aluminum work. All I can tell you is I set the gun / machine like the instructions said to and then just played with feed speed a little. It doesn't have the nice "row of dimes" finish look of Tig, but it works and makes solid welds. If you have verified all settings, then I'd guess something like a bad connection mentioned above.

 

[sberry]

Look at the door chart,, it takes fairly hi wire speed and long stickout, is fussy about gun angles. if it is burning back speed is too low.

 

[MoonRise]

Aluminum is hot-n-fast for GMAW.

Burn-back usually means you don't have the WFS set high enough (or you have the voltage set too high for the corresponding WFS, the two setting/parameters have to 'work' with one another).

Also, make sure you have the right size tips!!! Since aluminum expands much-much-much more than steel when it gets hot, the 'special' contact tips for aluminum are slightly oversized (on the hole diameter) compared to a 'regular' tip. You start welding, the tip and the aluminum wire start to heat up, the aluminum wire expands and binds just a little bit inside the tip and BLAMMO, the wire then slowed down just a tiny bit and thus melts all the way back to the tip and fuses into the tip. GRRRRR.

Also, unless your 211 has the 'snot' to properly drive the wire, most of the 'small' MIG machines (lower than the 250-class) usually do not have the proper voltage/amperage profile to drive 5356 filler (which takes more voltage to 'drive' than 4043 filler). RTFM! Although 5356 is a stiffer wire and thus folks think it will feed better than 4043 filler, if the machine does not have the extra voltage to run properly you can't get a decent weld anyway.

Although 6063 can be welded with either 4043 or 5356 filler (and each filler has its own advantages and disadvantages), if the machine does not have the proper voltage-amperage profile you may not be able to run 5356 filler.

OK, so I just went to the Miller website and looked up the manual for the MM211 (with auto-set) and the parameter chart on Page 28 specifically says to use 4043 filler for aluminum (either 0.030 or 0.035 wire) and obviously 100% argon shielding gas.

For 1/8 aluminum, the suggested parameters using 0.035 4043 filler are 5.5 on the voltage and 65 on the WFS.

Also, for GMAW you usually want to use a 'push' and not a 'drag'.

If there is slag, then drag. FCAW or SMAW (aka stick) have slag, so a drag motion is used there.

I'll bet though that just going to the listed/recommended 4043 0.035 filler (not 5356!!!) with the spool gun and the suggested parameters and using a 'push' should get you going.

Go get some more contact tips and a spool of 4043 filler and try again. Let us know how that works.

http://www.millerwelds.com/resources/articles/index.php?page=article152.html

http://www.assemblymag.com/articles/86511-troubleshooting-the-mig-welding-process

http://www.welding.com/articles/bparticle3.asp

http://www.weldreality.com/spray transfer 2.htm

http://www.millerwelds.com/om/o239988j_mil.pdf

Manual for the Spoolmate100 spool gun

http://www.millerwelds.com/om/o234016f_mil.pdf

Note the Tips/Troubleshooting section on Page 40, "Wire burns back to contact tip"

Wire burns back to contact tip during or at the end of the weld.
1. Maintain a 3/4 in. (19 mm) tip-to-work distance.

2. Check to make sure the contact tip size, drive rolls and gun liner match the wire diameter that you are using.(Sometimes an oversized tip can be used. The ID should only be one size larger than the wire diameter.)

Use the right wire (4043), the right parameters, the right contact tip, and the right tip-to-workpiece distance (3/4 inch in this case)

 

[steel 35]

I also fresh clip the wire every start for aluminum and the tips I use have a half steeped.

 

[kellymc]

It's the tip design of the spool gun, search around on the net, there are instructions on how to convert the gun to take standard mig tips. The way the tips are designed with the taper allows them to overhead quickly, which leads to the wire melting to the tip before it comes out of the spool gun.

I fought mine for a year before I made the modification to use the standard tips. I haven't had a problem since.

I also run .035 wire but use a .040 tip, works much better as well.

Kelly

 

[Bobhdus]

I don't know about all the different Miller welders out there but I have always had to use tips that were the next size larger than the wire with our Miller 30A Spool gun. One poster mentioned checking to make sure you didn't lose a leg on your voltage (or issues with gun itself). If these things are good then I might suggest that when you start welding, curl the wire or angle the gun a little so the wire doesn't hit the aluminum straight on. Some spool guns will say to rotate the spool housing in the direction your welding so that the unrolled wire will curl in that direction automatically. I don't know what your experience level is but when you first start to mig weld on cold aluminum, it will weld rough the first pass or so but should smooth out and weld better as the heat spreads (or you can preheat). Let us know what you find. Thanks!

 

[Fireguy268]

I Know EXACTLY what you are talking about because I have pretty much the exact same set up, a Miller 211 with the 100 spool gun, although I gather your gun is the 200. I had the exact same problem, I tried everything, stick out distance, wire speed, voltage, another roll of wire, different tip sizes, adjusted roller tension, I changed to another bottle of Argon thinking it may have been contaminated. I even spoke to the warranty repair facility here without much help and I finally found the problem and MoonRise nailed it.

Like you I was using .035 5356 wire. Change your wire to .035 4043 and prepare to be amazed. It's an absolute night and day difference. I set my machine for 3.5 on the voltage and 85 on the wire speed and I seem to be getting some great results and I haven't melted a tip since. BTW use a push angle not a pull.

 

[Debriefer]

I apologize for the thread necro, but I want to follow up, and all the context is here.

I cleaned off the oxidation layer on the workpieces, bought 4043 wire to replace the 5356 I was using before, and I followed the chart on the door of the welder, and lo and behold: a few decent beads! It's amazing how fast it is compared to steel.

Thanks for the tips everyone. Pun intended.

 

[MoonRise]

Glad it's working for you now.

The 'right' filler (for the job AND the machine) makes a difference, eh?

4043 filler for pretty much all 'small' wire feed machines (pretty much anything smaller than the 250-class machines), as they don't really have the voltage-vs-amperage output curve to 'drive' 5356 filler.

The 'big boy' machines (250-class or bigger) have enough voltage-vs-amperage to drive almost any wire you can get. And the adjustments to set that voltage-vs-amperage (and WFS to with it all).

So, to sum up, RTFM for the win, eh?

 

[TheEquineFencer]

I apologize for the thread necro, but I want to follow up, and all the context is here.

I cleaned off the oxidation layer on the workpieces, bought 4043 wire to replace the 5356 I was using before, and I followed the chart on the door of the welder, and lo and behold: a few decent beads! It's amazing how fast it is compared to steel.

Thanks for the tips everyone. Pun intended.

I'm glad you posted this. I learned a fair amount from it. I have a new 252 Miller with a Spool Gun I've yet to use. I'll need to find out more in here before I even start to try to weld with it .

 

[svtankgirl]

Hey...I just gotta thank you guys for the above info. I switched from 4043 to 5356 tonight and was losing my mind a bit. Everything went from hunky dory to WTF! Tips melting away. Also, I jumped up from .30 to .35 just for a test. I noticed angel hair skimmings back at the drive rolls though I read the machine will do .35 in a forum.

Has anyone run 5183 through a smaller MIG like a 175? I used lots of that in the past, and a little 5356, but I hated the dirtiness of the 5356. 5183 ran very clean. Cost was maybe 15% more and well worth it on a big project. Just curious.....

In the past I was using a fronius tips 2700 and it is simply amazing. This is a cheapo Eastwood MIG 175 with the ally spool gun. I didn't expect much but was very much surprised how well it works. For monkeying around and small stuff fine. I'd say forget going over 1/4" alum and any projects that need the duty cycle. Also things get hot fast on the torches. Just in case anyone is interested.

Thanks.

 

[sberry]

Alum is a push angle also.