Technical Wft is wrong with my mig welder?

I've seen it mentioned twice in this thread now where guys have felt that the tensioners to drive the wire needed help, either reinforced or clamped together to help drive the wire, adding more tension etc.

Well, in the majority of cases, the drive tension arm, springs etc. is not the problem.
They don't need to be replaced or clamped or beefed up and more tension is not the issue. In fact trying to add more tension can make things worse.

What the issue is in most cases is the drive motor itself. It can still be operating (running) but the main drive roller is mounted to the motors shaft.
There is a bearing or bushing on the output shaft of the motor and it gets worn out from over tensioning the drive rollers or just plain use and age.

If you can grab the main drive roller (without the tensioner on and no wire in place) and wobble it up and down, then that indicates that you need to replace the drive motor as the main shaft bushing-bearing is shot and that is the source of your wire drive problems.

That causes the majority of wire drive issues.
My son got a smoking deal on a used 220V Miller welder ( almost free ) that the guy thought was shot and all we had to do was replace the drive motor for $140.

 

While we are discussing drive problems, I will add that it took me literally years to figure out why my miller 210 sometimes didn't want to push the wire. Finally after asking a lot of questions, the miller dealer asked if I had any tight loops in my cable. That was the problem. Now, I look at the cable to see if there are any tight loops in it before I strike an arc. Apparently, even with a good liner, the wire won't feed smoothly if there is a fairly tight loop in the cable assembly. I kinda feel like a dummy saying this, but it was a simple problem, and perhaps I am a simpleton, but I hadn't considered that until someone pointed it out to me. Not necessarily your problem, but I thought I would add this to the mix when the discussion turned to drive problems.

 

I'll be checking that out Larry, thanks.

However ,
The little tension arm does have some distortion issues.
New replacement arms are available at about $16.00
It's not very positive attachment in the plastic pins going into the plastic holes. Plus it's a bend to fit and hope for the memory in the plastic to hold it in.
Mine seems to rock about the wheel. The pin or hinge end of the arm does go up when the spring is engaged. When that end goes up the spring end of the arm bottoms out on the main body of the drive assembly and there's is little if Any tension on the drive roller. Any slop in that bearing you speak of would compound the problem at least 3 fold.

 

Not saying this is the case with 32 vicky but many of the issues with the "offshore" welders is the drive system, alignment and the crap bearings they use.

I too struggled with the cable deal until I realized what was going on, and I gotta say this; if I did more welding I would replace the "firehose" that Miller supplied with my 200 Millermatic, just couldn't justify the cost of a Tweco changeover.
I ran the toolroom at work for many years, we would buy Tweco cable liners by the case, but when I talked the fab shop leadman into educating his new hires about the cable radius restriction our liner replacements dropped considerably.

 

We had guys who insisted that they needed a 20 ft tube on the feeder and constantly had problems. The welders we used had movable feed mechanisms with 40 feet of cable. I used an 8 foot tube and never had problems. Another thing we ran into was inconsitant wire diameter.

 

Since we are now talking about the wire drive, I agree with the inconsistent wire wire diameter, it was really a problem a couple of years ago when they started importing a lot of china wire. It got bad enough I started paying 2x the price to get made in the USA wire and a lot of that problem went away. I believe the diameter consistency has improved a lot since then.
Another thing you may want to check. I run the same size wire all the time. I had to replace the drive rollers a few years ago, it seems that with time and a lot of use, the slot the wire feeds through becomes oversized. Who would have thought? I didn't. Gene

 

I just went through this with mine, would weld nice then all of a sudden start shooting ducks, sometimes it would start the weld perfect then other times it would bang and thump and not start the weld , I did the usual, new liner, new tip, checked the drive motor and tension etc etc etc , I took the machine completely apart and cleaned and inspected everything, put it back together and it worked great , well for about 5 minutes and did it again.... I parked it in the corner and borrowed a buddies to finish the project. Well after being bored because of weather I took it apart again down to every nut, bolt and screw , cleaned and inspected every inch of every piece of it and finally found the culprit!
The trigger in the gun has tiny micro switch that contacts the backside of the plastic trigger. well after 15 years of use it had made a little divot in the trigger which caused micro switch to not fully click, new trigger and micro switch ($26.00) and it welds like new !!!

 

Very informative stuff thanks guys.

 

The shaft wobbles up and down like a hot dog down the hallway.

 

Yikes, well time to get the serial number and model number and order up a replacement motor.
That and fixing the other assorted worn out stuff like the pivot points for the drive tensioner and you’ll think you have a brand new welder

 

Yeh, sometimes it strays from the original post but who knows what useful little tidbits come out of these threads.
When I got my Miller years ago I initially set it up with .035 wire but I had some floorpan work to do on my Nova so I changed it over to .023 wire. It seemed like no matter how much tension I set on the rollers it would either not push the wire (too tight) or if too loose all it would do is "rat nest", boy I wasted half that spool before I finally got creative.
I had a leftover plasic number panel from when I raced shifterkarts, I made a little hinged flap that lightly rested on the wire between the spool flanges, this allowed a lighter tension setting and eliminated the rat nesting, made for happier welding even though I still couldn't see for s#/t, but that discussion is for another thread.

 

Metallizer guns drive a pair of mig
wires, we often had drive problems like these, and sometimes wire dia varied!

 

Puff of smoke ? Oh I see you want to ask Jeannie for answers to your welder problems !

 

Who me?
I'd be asking the Jeannie for a brand new welder and a never ending little somethin' somethin' . No need to bother her with silly questions, that's what this place is for.