Getting started w/ Mig

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Hello everyone!  I've had this old lincoln LN-25 suitcase in my shop for awhile and I never used it, decided its time to move up to Mig welding if I can get my stuff fixed up.  I've got an old miller dialarc 250 ac/dc that I've been using for a very long time now.  I haven't really used it much, but its been sitting in my old dusty shop for years.  Someone last year also stold my welding leads and even cut the power cable off, so I've recently jumped in and decided to fix it all up.I've got 2 awg welding cables and I"m running the miller at 230 volts, the jumper leads are setup right from the chart, however behind the terminal there are two burnt leads and I can't really tell where they go to but I'm guessing the fan because the fan isn't kicking on at all.  Now I can still turn it on and weld with it, it seems to weld properly and all and I do have a box fan setup where I took the sides off to blow air through it.So I go ahead and hook up the LN-25, I've set it to positive electrode and hooked the positive lead onto the lead coming out of the suitcase that runs through to the welding gun.  I've got the LN's work cable hooked up to the Millers work cable and I am getting an arc... but its not holding steady its like zzzzzz.....zzzzz.....zzzzz, cranking my ampeage on the miller up and down has no real affect.  I've also noticed that the voltage indicator on the LN is pegged out up over 40 volts.I haven't been able to hook the gas up because I need a brass fitting for my big argon tank, it takes about a .97" or .98" male fitting and I've got all kinds of regulators but none with that type of fitting .  But I believe it should be holding an arc still right?I'm hoping someone here knows these units well enough to help me out with a few questions.Is something possibly hooked up wrong?  Shouldn't it be putting out around 24 volts?  What can I do to help get this unit operating smoothly?I've just got myself a job in the mining industry repairing mine equipment and simply using acetylne torches and stick welding isn't cutting it so far as advancment lol, I've got to learn MIG and plasma... I think I can handle the plasma cutting at work but welding up and in tight places with the MIG is alot different than what I'm used to with stick so I'm trying to pick it up by practicing with this suitcase if I can get it lined out!Thanks all who reply for your time!
Reply:The Dialarc is a CC machine. Mig is usually a CV process. It is possible to run wire from the LN25 with a CC machine, but it works best with large diameter flux core wire in spray. Typical short arc mig with solid wire will not weld well because the feeder can not adjust the wire speed fast enough to mimic CV.Sort of need more info on what size wire and type you are using, but if you are trying to run solid wire you will probably have issues unless you know what you are doing and all the parameters are right. You really need a CV capable machine for solid wire under most circumstances..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:The wire in it looks to me like .030 solid steel, the LN has a switch to go from CC to CV but alas I'm stuck with what I got!  I can run up to 1/16" flux core wire, I probably should be running the gas with that wire for sure right?Know where I can find brass fittings for my regulator and tank?
Reply:Solid wire requires gas. Also make sure the LN is set to CC with the Dialarc. As far as fittings I get most of mine from the LWS, though Tractor Supply has a decent selection if I need stuff in a pinch on Sat/Sunday.I'd suggest you run FC wire, say .035-045 if you want to have any chance this will work. Solid simply will not work well. If you need to lay down lots of metal, FC or dual shield will be the only way to go with that rig. Remember that to work, you will have to have the amps cranked up to get the set up into spray mode. Vertical and overhead in spray is a PITA to run. There's no getting around some of these issues unless you get a CV power source. Thin material and solid wire will require you get a CV machine, or a dedicated mig..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:You will not be able to burn .030 solid wire  with your ln feeder. As was mentioned even with the machine set to cc  it cannot sense and control the voltage fast enough. It will work quite well with .045 self shielded or dual shield and even better with 1/16th or ..068.
Reply:So could this be why I'm not getting a 24v current?  I'm getting almost double that but that is still within the LN's operating specs so I hope thats cool.  I think I'll get some large diameter FC and DS wire, so I am guesssing I should probably run the largest diameter wire I can which would be 1/16".I'd like to have a Mig machine, but I can't afford it I'm stuck with this for now, if I can get my welds burned in good I can take some work that will finance better stuff though.Then again I'm wondering now if simply stick welding would be superior, this miller using 7018 rods really makes some very pretty welds if I do say so myself lol.  Then again I'm just not used to the wire feed, maybe when I get some practice in after ya'll so generously straighten my setup out I can do just as good quality much faster than before.
Reply:I don't know that feeder well, but what you may be reading is the open circuit voltage for the CC power source. Keep in mind the dialarc doesn't put out constant voltage, only constant current, so the reading on the voltmeter may be pretty much useless except when you are actually welding, and maybe not even then..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan