changing the spool in a MIG welder

[larrynjr]

Still being new to welding and getting close to the end of my first spool, I was wondering; when the old one runs out do I yank the wire in the gun out or just put in a new spool and it will push out the old wire with the new?

Also, I think I know the answer to this one from other posts but as I was welding a new metal table for my gas forge today, towards the end of what I was welding I began to notice that the wire wasn't feeding consistently. I've read here that dirty / rusty wire will do this but this is a relatively new spool and I'd already used quite a bit of it prior to the feeding issue. Should I adjust the feed rollers or clean them?

[Dodge]

Larry,
You need to pull the last of the wire out after it runs out of the feed rollers. If you don't, you stand a good chance of the new wire to jamming inside the liner. On the big industrial machines I used to run, guys would sometimes pull it through just enough to get the new wire started, thinking they might save some time or just forgetting to finish pulling it out and then spend the next 20 mins taking the liner off the wire feed unit and unjamming.

If it starts feeding good it should end feeding good as a rule. Are you exceeding the duty cycle by the end of the weld? If the rollers are getting dirty, the wire is where its coming from, most likely. Is the spool inside the unit or outside? One way to keep the wire "dusted" off is to take some folded up paper towel and clip it around the wire before the inlet tube to the rollers. Just get one of those big clamp type paper clips from the office supply and let it hang on the wire. This wipes the wire as it comes off the spool. Make sure it doesn't ground out on the wire anywhere. Change the paper towel periodically or the wire will cut through the paper and the clip could ground out the wire and then you have a real mess of spaghetti

Hope this helps

[hammerkid]

I pull out the old wire left in the lead(gun) then feed the new wire throw it . I reckon your mis up the liner if you don`t ! Also if you use rusty wire it takes a toll on your liner life

[keykeeper]

What Dodge said. Also, instead of paper towel, I've heard using a piece of scotchbrite pad works also, cleans the wire well before entering the liner. Lasts a little longer than towel. Haven't tried it yet, but will as I'm using an older mig that likes to jam up on the feed every now and then.

-aaron c.

[larrynjr]

It's quite possible that I was getting past the duty cycle of the unit, it is a pretty low end unit. I considered that as well but not having the experience I wasn't sure. I'll do the paper towel / scotchbright cleaner solution as well. The spool is inside the welder.

I will strip out the old wire for sure, don't need the hassle of trying to clear out jammed wires!

Once again, Thanks to everyone here!

[Covforge]

Larry, Keep an eye on your lead. Sometimes it can kink like a water hose. Expecially if you are stretching to get that last little bit befor you reposition.
Travis

[brucegodlesky]

I use the scotch-brite trick, has worked well for yrs.

[habu68]

scotch brite and a spring type clothes pin, here.

[larrynjr]

I think I've discovered what the issue is, the gun hose as it connects to the welder itself doesn't seem to have a solid locked in position and after moving around from weld position to weld position seems to work it's way loose. Push it back in and it feeds fine. I didn't take the time tonight to look closer and see if I've missed something in my setup that will keep the connection tight.

[larrynjr]

So I finally did look at the connection and there is a screw that locks the gun hose in place but that didn't solve the feed problem either. I brought it with me to Brad / eburgblue's place yesterday and had him look at it and he wasn't sure either. I started messing with it again today and discovered that the wing nut that holds the spool in place turns with the spool and tightens up until the spool won't move anymore. I added a lock washer and really loosened the wing nut and now it keeps the spool in place without over tightening or letting the wire unspool to much.

One of the techniques Brad showed me to inprove my welds was to try to have my arms and body leaned / braced against something solid while I make my weld. I had been trying to weld without any sort of stance brace at all. My welds improved immediately as did my O/A cutting ability.