Need to weld Aluminum and Need help...

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I have a Lincoln Mig-15 and I need to weld aluminum. I know I need a spool gun of some sort, but thats all I know. What type of gun will work? Would something like this work... http://cgi.ebay.com/MIG-WELDING-SPOO...QQcmdZViewItem Has conections for power, 2 connections to drive the motor and a connection for gas. Thats all I need right?
Reply:I don't know what a Mig-15 is, but I do know that none of the older small Lincoln MIGs will support a spool gun.   There is one available for the new Pro-MIG 180, but it's expensive.You can weld aluminum, with a small Lincoln MIG, and without a spool gun.    I do it all the time using a Weld-Pak 155 and now a Pro-MIG 175.     Plan your work so to keep the torch cable as straight as possible.    I zip tie a length of PVC conduit to my torch cable to keep it straighter.Set your drive roller tension as light as possible and still feed the wire.     You can save yourself a lot of headache by using 5356 wire istead of 4043.    4043 is like trying to push cooked spaghetti up drinking straw.    5356 however may cut into and prematurely wear your teflon cable liner.Good Luck.There are no small projects
Reply:Sorry, the Mig-15 is basicly a SP 175 thats sold in Canada. Pretty much the same machine. With a few modifications would I be able to use that spool gun? The power connection should be easy enough. Shouldnt be that hard to tap into the trigger and gas connections to make it work? Other then that is there anything else i'm overlooking? I considered a teflon liner, but everyone i've been talking to says to stay away from them. Any other opinions? Are they really ok if kept straight?
Reply:MMurray,I've tinkered around a bit welding aluminum with my small mig and feel it is just fine if you don't have too much of it or any strange position issues.If you can get a hard plastic liner (first) or teflon liner (2nd), it will make it easier to push the 4043 filler.  You may want to try 5356 for some alloys but it has a higher melting point and our 175 class machines don't need the strain.Also, while I can get .035 to run the .030 runs much better and the slick liner helps the thinner materiel thru the gun.  The .035 will feed thru my regular liner better since its more rigid.The most important thing I've discovered is being able to back the drive roll tension off to the point the wire slips when stopped yet still feed reliably.  So far the best way seems to be to set the wire spool tension to just over free spooling and then the wire feed tension where you can manually turn the wire spool and just pull the wire back out of the gun with the tension rollers engaged.  When you pull the trigger and run the wire into a board it will bend the wire and the roll will slip instead of birdsnesting.  Of course you need to get in the habit of quickly getting off the trigger too.Once you get to where you're not constantly dealing with birds nests you can focus on the welding.  The other real advantage of using a dedicated to "aluminum only" liner is you minimize contaminating the filler.I use a .035 tip when running the .030 wire because the wire can expand and bind in a .030 tip.  Burnbacks are a real issue and if you cannot setup to where the wire feeds reliably without slipping yet slips when restricted, you'll constantly be replacing tips.  It happens really fast too.  You'll want to keep the gun more perpendicular to the weld and run more stickout than you may be used to.  I find starting with 3/4" stickout helps me get going although I tend to get closer as things heat up and I get moving faster.  Its real easy to turn the torch too much and have the arc cut back to the tip on you - Especially going around tubing notches or corners.One thing neat about the aluminum is due to its lower melting point we get to experience spray transfer with our small machines.  Its so much nicer than short circuit.  I can see why folks want the larger machines so they can do this with steel.BTW, I've done this with a Hobart Handler 135, HH175 and now an HH187.  the 135 ran a nice bead on coupons but didn't have the oomph to give me a good weld on joints.  Oh, it looked nice but didn't hold up.  The HH175 and HH187 welds will.  Bet your 175 amp lincoln will be similar.I think lincoln offers an aluminum kit which may be nothing more than an oversized tip, liner, and u-groove roller.  If you cannot get them individually or can't get the wire to slip properly in the standard roller you may wish to consider the kit.  But, if the wire tension can be adjusted to work with the standard roller you may want to just use .030 wire and .035 tips.  Heck, you can try it with the liner in your gun as is just to see how you do.  If it works out you may wish to get the slick liner later.Have an open mind and good luck,Clay
Reply:Originally Posted by Clay WaltersHeck, you can try it with the liner in your gun as is just to see how you do.  If it works out you may wish to get the slick liner later.
Reply:Imagineer,You've run around 5 times as much thru yours than I have mine.  But, because I was having difficulty getting a nylon liner in my newest machine I just decided to give it a whirl with the standard liner and .030 wire this past Saturday.  Figured my liner was new and not contaminated yet but did fear the birdsnesting would rear its ugly head.  Fortunately it didn't but then I never really let the whip get in a bend of any kind.  Also my spool was pretty full.  My experience is as I get closer to the bottom wraps (tighter) I experience more hiccups in wire feeding and the resulting burnbacks.  Were I going to work on a project worthy of it I think I'd go with the 8" spool because the larger wire circle would furnish more leverage to the drive motor's advantage and minimize the natural bend in the wire that the liner is having to tame.Have never used nor even seen a spoolgun in action.  They sure sound neat but unfortunately on my machine a controller and spoolgun would cost more than my welder did.Regards,Clay