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bob ward
12-06-2012, 09:53 AM
I have one of these little WIA 150S mig welders which I have always used with argon. Its 15 years old and has had an easy life, if I've put 200kg of wire (usually .9mm) through it I would be surprised.

Problem I'm having is that while the wire feeds freely when not striking an arc, when I go to weld, the wire stops feeding. The feed mechanism is turning but the wire is not feeding. If I then point the handpiece up in the air and pull the trigger the wire feeds freely again.

The wire seems to be sticking in the current pick up tube which is to the right of the wire feed. The wire feeds from left to right, the actual current pick up tube is not visible but it stainless and about 4" long.

Over tightening the feed roller pressure is counter productive as eventually the wire just crumples into a ball between the feed and the current pick up. I have minimum drag on the wire spool.

I have a temporary fix which is to put a tiny bit of anti-spatter spray down the current pick up tube. Its a mickey mouse approach which gets the welding job done, but I'd really like to know why I'm getting the wire sticking problem in the first place.

Any thoughts? Could it be a function of the mig wire that I'm using rather than the welder?


http://i237.photobucket.com/albums/ff28/sirrobertthegood/IMG_0048-1.jpg

http://i237.photobucket.com/albums/ff28/sirrobertthegood/IMG_0051.jpg

Willy
12-06-2012, 10:09 AM
Are you keeping the feed cable leading to the torch/gun as straight as possible, no sharp bends or kinks in the cable?
Does the mig gun/cable have the correct size of liner, contact tip, and gas diffuser installed for the size of wire being used? Has the cable been damaged in the past due to kinking or has it been subjected to any stress like being run over by a vehicle for example?

The fact that it feeds when you straighten the cable and or lube the wire leads me to believe you have a minor restriction in the liner/gun assembly.
Obviously over tightening the drive roll pressure is not effective in over-coming this extra resistance as it will only bird nest instead of feeding.

Shuswap Pat
12-06-2012, 10:09 AM
You probably have a liner problem- the feeder is pushing, but nothing coming out the gun. First check your whip for any kinks, then check the tip to see if it is burnt, blow out the liner and pull the diffuser at the gun end, and check it out. and you should keep a spare of each (liner, diffuser) on hand. We also use a little foam 'marshmallow' that the wire runs thru, infront of the feeder - this has a couple of drops of oil on it, and lubes the wire, but not enough to cause weld problems. Good luck

Patrick


I have one of these little WIA 150S mig welders which I have always used with argon. Its 15 years old and has had an easy life, if I've put 200kg of wire (usually .9mm) through it I would be surprised.

Problem I'm having is that while the wire feeds freely when not striking an arc, when I go to weld, the wire stops feeding. The feed mechanism is turning but the wire is not feeding. If I then point the handpiece up in the air and pull the trigger the wire feeds freely again.

The wire seems to be sticking in the current pick up tube which is to the right of the wire feed. The wire feeds from left to right, the actual current pick up tube is not visible but it stainless and about 4" long.

Over tightening the feed roller pressure is counter productive as eventually the wire just crumples into a ball between the feed and the current pick up. I have minimum drag on the wire spool.

I have a temporary fix which is to put a tiny bit of anti-spatter spray down the current pick up tube. Its a mickey mouse approach which gets the welding job done, but I'd really like to know why I'm getting the wire sticking problem in the first place.

Any thoughts? Could it be a function of the mig wire that I'm using rather than the welder?


http://i237.photobucket.com/albums/ff28/sirrobertthegood/IMG_0048-1.jpg

http://i237.photobucket.com/albums/ff28/sirrobertthegood/IMG_0051.jpg

rollin45
12-06-2012, 10:32 AM
I would try blowing the liner out with compressed air, sometimes accumulated dust/debris from the wire will partially clog the liner. If this doesn't help, try replacing the liner... over time the wire will wear grooves in the liner and cause the wire to stick with the result it feeds erratically. I like to clamp a little piece of cotton or cloth around the wire just before it enters the liner, clamp it with a clothes pin or a bent wire, not clamped hard enough to interfer with the feed, but enough to prevent loose dust and dirt from entering the liner. Good luck, sometimes this can be a frustrating problem ...

rollin'

EVguru
12-06-2012, 11:18 AM
Is it a plastic liner or a steel one? I'd expect a steel one on a torch with a Euro connector, but in any case liners are a consumable. Pull it out and see if there are any kinks in it and note home much rubbish comes out of the liner. There's usually another short liner in the neck too and don't forget the tip!

outlawspeeder
12-06-2012, 12:06 PM
It looks too good to be dirt or worn parts. A quick check is to lay your welding cable out in a straight line. Try welding. If you have less problems it the liner. If you have the same look at the driver wheel.

Common problem to look at:
Wire crossed coming off the feed spool.
Spool wing nut tight or not installed right.
Wrong size or worn driver roller.
Dirt in trigger.
Wrong tip. Too big or too small will cause problems.
Burr in the tip.

chevy3755
12-06-2012, 12:13 PM
i would guess maybe a liner.....

Black Forest
12-06-2012, 12:28 PM
How long has your spool of wire sat in the welder? Look to see if there is any corrosion on the wire. If there is get a new spool. If there is any corrosion you need to toss the wire. The corrosion plays havoc on everything upstream of the spool. Also you need to replace the liner when you replace the spool.

ogre
12-06-2012, 01:29 PM
I have heard that the copper coating on the wire that prevents wire decay can fill the liner up w copper material and cause problems but this is just something a daily welder told me and not sure if true.

Pherdie
12-06-2012, 04:27 PM
I had the same issue once.

I found sufficient material had been eroded at the replaceable torch/gun tip such that the wire was pulling current through the pinch roller drive mechanism and therefore tack welding the wire to the drive roller.

Replacement of the tip eliminated the problem.

danlb
12-06-2012, 05:18 PM
My MIG unit has a slight difference in the feed mechanism. Where you show the left hand guide to have a tapered tip, mine has that on the right too ( the outfeed side). This lets the guide be adjusted to be very close to the roller and therefore less unsupported wire that is being pushed.

Dan

MrFluffy
12-06-2012, 05:44 PM
I had the same issue. A entire replacement torch (no liners available from snap-on) was fitted and it welded fine after. If you have ever ran corroded wire through it (and I always have to strip the outer layer back on mine I use it so infrequently) it scratches the liner and fills it with horrible deposits.
I just wish I'd had the foresight to convert it to a euro plug and use standard torch parts while I was at it the 10 years ago since I did it as its wired in snap-on/taskmaster/cebora stuff and needs doing again.

Deja Vu
12-06-2012, 05:44 PM
My MIG unit has a slight difference in the feed mechanism. Where you show the left hand guide to have a tapered tip, mine has that on the right too ( the outfeed side). This lets the guide be adjusted to be very close to the roller and therefore less unsupported wire that is being pushed.

Dan

Yup, mine has the cone guide on the outfeed too and is very close to the drive wheels.
But this may only overcome the original problem. I'll bet the whole line is somewhat "sticky" from age
and not-so-frequent use. Particles could be "rolling" in the line and occasionally binding. Especially when the line is not the ideal straightness while welding.