Welding Tips and Tricks

I bought a second hand MM250X a whole back. One of my main concerns was a 12" section of the whip was damaged right behind the gun. I disassembled it, cut out the bad stuff and put it back together. It has been working fine for a month or so until I developed a gas problem. While investigating the gas issue I took the gun apart again and found about half the conductors from the power supply didn't stay locked down in the compression fitting at the base of the gun. These were a bear to deal with the first time and I thought I had gotten them clamped down but evidently not.

My question is...what is the trick to get all the wire into the connector and manage to get it tightened without them squirting out? Used to be an electrician and have worked with a lot of different connectors but this one doesn't seem like the right one for the job.

Any advice?

The culprit -

hey,

the only thing i can think of was the the way our sparkys put lugs.on earth clamps and the like....

The cut the cable off square and then cut 2 15 mm wide slices around the insuation. as if you were going to strip it. this is the important part. slice and remove the second slice of insulation exposing the copper wire. the one closest to the cut end remains on and keeps all the strands in place.

Push this first section down the cable slightly to expose some copper at the end. tuck this (hopefully neat) end into your fitting. as you push farther in, the ring of insul will be pushed down the cable into the space vacated by the removed ring of insul. as you close the gap, remove the second ring of insul that was used to hold everything together, as it all should be nicely tucked into the fitting.

Phew. I do not know if this will aply to your mig gun, but fingers crossed.

Mick

Thanks for the idea Mick, only problem is the room for the wires is so tight I would never be able to get the insulation started into the connector. The first time I repaired it I was very careful to keep the strands neat and clean. Even with tidy strands it was very tight getting all of them into the connector deep enough to be caught by the compression fitting (I need 4-5 hands for this job...). I could get them started, but as soon as I started turning the compression fitting, they would simply squish out.

I tried tapering the wires slightly to allow me to push them further into the connector...same result, they squished out as the connector started tightening. A big part of the issue is in order to get the wires in far enough, I have to have the outer ring of the connector unthreaded. If I try to catch a thread or two before putting the wires in, I cant get the wires to stuff. With the outer ring off the threads, I can get the wires in place but I can't get the ring to catch threads because of the thickness of the wires holding the ring off...

I'm guessing there is a specific technique to get this thing back together but I can't find instructions anywhere and no one seems to have dealt with this before.

Hey,

Ill ask one of sparkys with welder repair knowledge and get back to you.

Mick

Well, $266 later all my problems are solved. I gave up on the repair and just bought a new 15' gun. All is right in the world again.

Hey,

Probably not a bad idea, since the other one is second hand,

I asked one of our spakies about it and he gave me a very quick rundown on the process.
I showed him your pic and he said it was the same set up as a bernard gun, which we use. Going on what he said, the brass collar should go over the copper, leading me to agree with you in saying the torch connector is wrong for the cable,

I also found avideo on you tube on how to replace a bernard torch. Gives a good overveiw of how the work. Might come in handy if you want to fix up that one as a spare.

http://www.youtube.com/watch?v=vLFPa8Rm ... ata_player

Glad you fixed your problem, hope you may be able to fix the other one.

Mick

Thanks Mick, I may try to fix the old one to keep around as a spare.

Sweet as mate, let us know how it goes, if it is too much of and issue ill get the spark to do a really in depth explanation . He was flat out yesterday and only had about 1minute to chat.

Mick

After I watched that video, I realized when I tried to put things back together I never removed the liner.... That might have been my problem.

Hey,

Not sure mate, i never have to fix things i only break em. I have been told im the reason for having maintenance electricians at work. lol

Mick.

weldin mike 27 wrote:Hey,

... I have been told im the reason for having maintenance electricians at work. lol

Mick.

Everyone needs a sense of purpose!