No announcement yet.

Help with 250X setup for aluminum

  • Filter
  • Time
  • Show
Clear All
new posts

  • Help with 250X setup for aluminum

    I've got 2 Miller MIGs. The first I've had since the early 80's when I owned a muffler shop. It's the old type with the 6 sockets for the main feed to plug into to regulate the heat. I've always welded mild steel well with it for an amateur. About 10 or 12 years ago I bought a 250X on a whim because I wanted to weld aluminum, but never got around to doing it. I've never gotten comfortable with the mild steel with it actually and can't seem to master the wire feed and voltage, which I have a good feel for with the old machine. The new one was stored at my son's house for about 10 years with no use and the manual is long gone, so I'm fumbling around in the dark. Current project is 1/8" 1 1/2" square tubing, not sure of the alloy. Although I've just got a knob on the bottom of the 30A spool gun, so there's no relative number to start with, I have no idea where to start with voltage AND also don't know what kind of gaps would be best between perpindicular tubes for good welds. I was thinking of starting at about 1/16th.

  • #2
    That's like saying I have a wrench, how do I rebuild a motor.

    Reading the owners manual is a good first step. I don't wish to sound mean or lazy in my reply, but there is no easy answer to your question and I'm not prepared to venture an attempt at one in reply.[0].key=processes_sm&filters[0].value=23e0fbc3175743449579d178af306c9b&filters[1].key=processes_sm&filters[1].value=826ebb0a37e7421abadac78d63c47595

    This should be close enough to get you pointed in the right direction.


    • #3
      When in doubt I practice on some scrap of the same product..........Of course with aluminum shorts it's easy to heat sink the scraps and give you a little different heat result than welding on something longer.........


      • #4
        I've read everything I can find to read and it's not helping with the aluminum. The troubleshooting the 30A spool gun doesn't answer my issues. First, no idea where I am with wire speed, but turning down from the previous setting of 8 on the gun back to 4 and I'm having trouble with the wire arcing on the feed wheel and bearing, and it appears the wire is soft back up into the gun. I'm down to 19 volts and it seems like the YouTube videos I'm watching are in the 19 to 21 volt range. The other thing I REALLY struggle with is feeding the alum. wire (.035) into the gun. It feels like a needle in a haystack and I can't get it through the insulator tube in the front without pulling it out, feeding the wire and then re assembling. This is after about 10 minutes with a pair of hemostats trying to find the center of the hole going forward. All of this stuff is virtually new and probably hasn't had 10 minutes total time since I bought it originally, at least on the spool gun side. I'm sure this is a great machine, although somewhat obsolete by today's standards, but the setup isn't detailed sufficiently in the online manual and the arcing at the feed wheel is a mystery.


        • #5
          After attempt number 10, which in all cases resulted in the wire wadding up inside the gun between the wheels and the tube to the front, both the geared drive wheel and bearing are now damaged from arcing beyond use. The wire feeds fine until it's put close to material and an arc is attempted. This is getting REAL frustrating.


          • #6
            Your wire is a bit small if you are using 4043 to learn on in my opinion.
            Go to .047 to begin and figure out what is happening here.
            Once you get it all working without mechanical issues then the settings will be easier to establish.
            It's been too long since I used my 30-A to remember any specific settings. The wire should be fairly loose in the tip so it can expand without galling.
            The 30-A has to be hooked up to the argon regulator directly not thru the machine. Also you need to pull the trigger partially for a bit to pre- purge the area. That could be an area of concern too.
            5356 wire is harder and bends less too. It is stronger as well.
            The 30-A takes a ton of gas to get it working correctly. You need a high flow regulator and a bunch of gas flow to maintain welding. Little ones don't work.

            Miller Dynasty 700...OH YEA BABY!!
            MM 350P...PULSE SPRAYIN' MONSTER
            Miller Dynasty 280 with AC independent expansion card
            Miller Dynasty 200 DX "Blue Lightning"

            Miller Bobcat 225 NT (what I began my present Biz with!)
            Miller 30-A Spoolgun
            Miller WC-115-A
            Miller Spectrum 300
            Miller 225 Thunderbolt (my first machine bought new 1980)
            Miller Digital Elite Titanium 9400


            • #7
              "2 Wire Speed Control Use control to adjust wire feed speed. The numbers in the opening are not a wire feed speed and are for reference only."

              I'm not sure if this will help or be accurate but here goes anyways. It sounds like as FusionKIng mentions, you have a few things to address. A stiffer wire either thru size or composition will be easier to feed. Then is the matter of voltage settings to the transfer mode in deposition. I'd be going up not down, but that again is my thinking that you need closer to a spray transition then a globular/ short circuit voltage transfer mode?
              Adequate shielding gas flow rates to provide a path of electrical flow and weld protection.

              As mentioned you could be getting wire swell with causes resistance to feeding and the bird nesting. More then likely your welding with to low of a wire feed speed and to short of stick out? The wire balls back and plugs the tip. As far as wire swelling, a larger contact tip orifice will prevent that occurrence. to large and you have poor wire contact, greater resistance heating (current loss) and wire hunting occurring.
              I'm guessing if you melted things inside then you had a short between the work and in squeezing the trigger found a way for the wire to no longer be insulated causing arcing? A picture of that would if nothing else gave us a reason to say holy smokes what a mess?

              But a couple of things. Check the drive rolls in the gun.
              "8 Drive Roll Groove For wire sizes .035 in. (0.9 mm) and smaller use small groove, and .047 in. (1.2 mm) and 1/16 in (1.6 mm) use large groove."
              Are they the right size for the wire? Correct type? How's the adjustment, or pressure against the wire for grip?
              Brake tensions on the spool?

              "The wire feeds fine until it's put close to material and an arc is attempted. This is getting REAL frustrating."

              Lastly...the dial on the gun. Remember your not welding with a steel wire. Keeping things simple, all that dial does is speed wire up or slow it down. You need to speed it up. At the same time, use a longer stick out.

              Hope it helps?


              • #8
                Thanks to everybody for the suggestions. I called our local Miller distributor today to order the new wheel and bearing, and he referred me to a service center south of Atlanta to ship the gun to for evaluation. When I spoke with the tech there he basically told me that the settings I was using for the wire feed were all wrong. First, when it was acting a little odd I INCREASED the tension on the bearing/wheel assembly, and that caused the wire to wad up in the gun with any resistance to the feed, and when it wadded, it arc'd at the wheel causing the wheel damage. He told me how to set the tension and also on the spool center nut also. SO, he's drop shipping a new wheel and bearing from Miller which I'll supposedly have Wednesday and we'll start over.