Snap On MW120 MIG Welder
- Thread starter RustyRatRod
- Start date
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Back to square one. Is the welder 120 volt wall outlet welder, or 220 volt 3 prong electrical plug?
120 amp welder?
There is a huge difference between a 120 volt and a 220 volt machine.
120 amp welder?
There is a huge difference between a 120 volt and a 220 volt machine.
???
It could be a 220 volt 120 Amp welder.
Needs to identify what it is. Gas Bottle welding or flux core wire?
Transformer is too small
I've said right from the original post it's a 120v machine.
I've said it was MIG with gas clearly before.
Reversing polarity is for flux welding.
Have welded with the .023 wire for auto body welding, but the liner/cable/wire had to be very straight or the wire would kink at the spools that drive it. Use .030 for all the steel fabricating work and it never bothers with the kinking at the spools. (220 volt 1800 Hobart). Using Argon Co2 mix for gas.
If what was said in post 41 is accurate, that could be the issue. I did install it and cut it with the liner installed in the gun just as described, but I used a cut off wheel. I supposed I could have tweaked the last few inches, because that's about when the problem starts occurring. I am beginning th think the problem is two fold. One, the feeding issue and two, the actual welding issue. Even when it feeds right...and it does every now and then, it still does not strike an arc really at all.....and yes, I've tried .023 wire in it. The wire size isn't the issue. It's something internal in the machine, I believe. I sorta know someone at the welding supply house in Macon. I'll chat with him Monday and see what he thinks.
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toplscuda
Well-Known Member
Rusty if you can post a picture of the welding gun that is on it. Many of the smaller Tweeco Lincoln or Miller guns will have the copper break where it is connected to the brass block that goes into the machine. That will cause poor welding as it cannot carry the current. I always tell customers don’t use the gun as a pull toy
Do you want me to remove it from the machine and get a picture of that end?
Ok, here is the machine end. I believe I have fixed the feed issue. I backed off a few coils and made a clean cut with a sharp pair of dykes and now it feeds really good. Still has the issue of not striking a proper arc, so it appears the problem was two fold. Thanks for the advice on how to cut the liner. I think that did the job with that issue. I need to call Kirk and see what wire he had in this last. It doesn't say MIG or flux, so I'm not real certain. I tried reversing the polarity anyway and it made no difference, so I don't think that's the issue either. I'm leaning toward something internal in the machine.
Just for the fun of it, hold the very end of the machine insert to the positive on a 12 volt battery. Then take a test light from the negative on that battery, touch the test light pointer to the copper welding tip on the tweeko gun.
Basically want to see if it is carrying a good 12 volts and a bright test light. If the test light is glowing orange, there is a poor connection in that welding lead.
Could possibly do the same test with an Ohm meter. Like testing a spark plug wire to see if it is getting full juice or has a leak.
Basically want to see if it is carrying a good 12 volts and a bright test light. If the test light is glowing orange, there is a poor connection in that welding lead.
Could possibly do the same test with an Ohm meter. Like testing a spark plug wire to see if it is getting full juice or has a leak.
toplscuda
Well-Known Member
On that end of the gun is most likely a rubber boot that goes over the brass a bit. On the Lincoln guns there is a spring clamp that holds it in place. I don’t remember about the Tweeco. If you are able to slide that back and verify that the copper wire isn’t broken where it connects to the brass we can rule that out as a cause.
The only thing rubber there, you cannot see and that's an o-ring around the bulb end of the liner, right where the wire enters it. Other than that, no rubber. There's a copper "strap" that the gun sheath slides into that's one side (positive right now) of the electrical. Come to think of it, is that strap supposed to be "tight" around the copper part of the sheath? It just slides in and out. Seems that would be a poor connection, no? I do know that Kirk was pretty frustrated when he tried to last fix it. Maybe he forgot to tighten it up? I haven't checked it, because I'm unfamiliar with that part of this welder. I've used it a good bit, but never done maintenance on it. I'll check it tomorrow and see if it needs to be tightened there. That might be just how it's designed. I don't know.
I went out and looked at it closely and as I said, the copper strap that goes around the metal end of the sheath was nowhere near tight. The small offset bracket, I believe Kirk reinstalled backwards and that puts the copper strap loop on the small part of the metal sheath, where you see the set screw is in the picture I posted above. I flipped the bracket around backwards and that puts the loop right on top of the bigger part of the sheath, farther forward and it did tighten up really good around the metal part of the sheath now ans makes good contact......I was hopeful, but the machine still does the same thing. However, it's feeding like a big dog now, at least. lol
Dfr360cuda
Diagnosis... Plum Crazy.
Contact tips on the gun trigger ?
Dirty contacts won’t pick the relay.
Dirty contacts won’t pick the relay.
He actually put a new trigger on it chasing the problem.
Demonic
Well-Known Member
So, the wire binds AND the current isn't flowing correctly? Maybe the connection from the gun to the machine? I'm assuming it disconnects?
No. I fixed the binding. Now all it's doing is sticking and melting the wire to the work, rather than making an arc. I got it feeding real good, though.
Hemirunner
Well-Known Member
I know you tried reversing the polarity earlier, but is the polarity correct for gas shielded solid wire? Do you have .023 or .030 wire in it? The others are correct that an 80 amp machine won’t run .035 wire.
I'm not sure what amperage it is. I haven't been able to find that information. ....and please understand here, I'm not arguing the point, I'm merely point out what this machine has done in the past. It has .035 wire in it now and it has produced some good welds with that in the past. But yes, I've checked and double checked the polarity and it is right for the wire that's in it.
toplscuda
Well-Known Member
I am not sure why many of you insist that a 110 machine will not run .035. As long as the machine is working correctly and you are not trying to run it off of an extent in cord it will run it just fine and get plenty of penetration as long as you are not trying to weld 1/2 steel with it.
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