what wrong????

[Sniper]

we have had a bester mig for about 10 months now it is not used all that often but just lately it has starting playing up it will work fine then the wire will start burning back up the tip and melting on the end of the tip when the trigger is released, we have played about with the settings but nothing seems to work.
one day it will be fine then the next it is nothing but trouble.

we had a eutectic castolin from the 80's before that and it was never gave us any problems.

anybody know what is wrong?

 

[Robotstar5]

When was the liner last cleaned out?

 

[Drains]

When was the liner last cleaned out?

And have you tried changing the tip?

Best thing - loosen off the feed rollers and pull the wire out through the torch by hand (or with a pair of pliers). How does it feel - is it free-running or tight? If tight or rough, change the tip and/or liner, or at least blow through the liner with compressed air and try again.

 

[Sniper]

The liner has not been done but it had got through about 20 tips, will try pulling the wire next week and see what it's like
Thanks

 

[s410man]

pull the liner out straight and then tie a weight to the end of the wire and see how much it needs to move the wire

should be way less than half a kilo

 

[Sniper]

got the gaffer to order a new liner today so hopefully it will sort it.
never replaced a liner before what is the best way of doing it, sorry if that is a stupid question

 

[Drains]

got the gaffer to order a new liner today so hopefully it will sort it.
never replaced a liner before what is the best way of doing it, sorry if that is a stupid question

Take the torch off the machine. The liner has a wee nut holding it in. Undo that and pull the liner out. To replace the new one, first remove the contact tip/adaptor from the torch then gently push the new liner back in the way the old one came out. Don't force it through as you might kink it.

Once it's through, it should be too long. Clip off the excess at the torch end, remove any burring, then replace the tip. As you screw in the tip it'll push the liner back a little, which should be fine. Don't forget to replace the nut holding the liner in place. Replace torch on machine and feed wire through. (I usually replace the tip after feeding the wire)

 

[Sparkey]

Just to clear things up a bit, this is the "wee" nut you have to undo:

 

[Sniper]

Thanks
got the liner today fitted it and it seems much smoother

 

[Tradesman]

Mig wire feed problems

I think it is highly unlikely to be the liner. In all the years I have been welding I have hardly ever found the liner a problem. I would suggest two things one have you tried another reel of wire and is the reel sitting with the peg in the reel hole. This is a problem I recently had. the other is the feed rollers are they the right grove for the wire and is the tension correct on them but do not over tighten them they should be just tight enough to grip the wire.

 

[Sniper]

So far so good with the new liner but it has not been used much with the new liner, the problem is the welder is by the door and it has been clipped by the forklift a few times so it may have been run over a few times.
I pulled the wire through by hand with the old liner and after I fitted the new one and it was a huge difference

 

[Sparkey]

So far so good with the new liner but it has not been used much with the new liner, the problem is the welder is by the door and it has been clipped by the forklift a few times so it may have been run over a few times.
I pulled the wire through by hand with the old liner and after I fitted the new one and it was a huge difference

Haha, well running it over with a forklift doesn't improve things really!
Hmm, if it's by the door...what's the state of your wire? it should be nice and shiny... did you change the tip too?
Are your feed rollers in a good state? (with your finger press the wire in the groove, the wire shoulden't sink entirely in the groove)

 

[Sniper]

the wire and rollers are fine, yeah changed the tip too.
the position of the welder's are dictated by the boss, I found a nice spot out the way for the tig but was told to move it along side the mig by the door

 

[Sparkey]

the wire and rollers are fine, yeah changed the tip too.
the position of the welder's are dictated by the boss, I found a nice spot out the way for the tig but was told to move it along side the mig by the door

yikes!
Oh well...it's the bossman who pays for the kit so...nuffin else to do than obey him...

 

[Sniper]

Yeah it is up to him, at least if they get damaged there he can not blame me for putting them there

 

[Tino]

Probably the worst place, typical boss. Bet its fun T.I.G welding in a breeze. Tungsten meltdown when your gas gets blown away.