Using up old welding wire.

[alanganes]

I have used a fine Scotchbrite pad folded over once or twice and stuffed into a binder clip as a wire cleaner. By using a large clip and varying the amount of pad stuffed into it I can get the thing to wipe the wire clean without unduly bogging down my wire feed motor.

[trevatxtal]

The main problem with old MIG welding wire is dirt or rust makes a poor conductor.
The following trick will reduce this and make welding smoother.
First obtain a a short length of TV coax Old Type or micro phone cable.
Strip out the coax braid 12.5 to 25 mm or 1/2 to 1 inch.
Remove the MIG welding copper tip.
Slide the coax on the wire and into the recess that the screw copper tip came out
When you have established the amount that will fit in easy cut the rest off.
Push the coax down in side and refit the copper Tip.
What this does is to create a multiple connection to the MIG welding wire via the coax.
This is also most helpful in prolonging the life of a worn welding tip.
(with me it is 5 times longer )
Replace the coax as soon as welding starts to stutter.
All the best Trev
PS I live next the Sea, I had to find a cure for corrosion/rust this was one of them.

[Highpower]

I ended up taking the easy way out.   

   

[EdK]

(02-22-2015, 02:19 PM)Highpower Wrote: I ended up taking the easy way out.   

As did I.

Ed

[Ozwelder]

The mig process is dependent on maintaining a high standard of cleanliness. It includes keeping the wire clean as well as the base metal.
Both  areas needs to be kept free of all possible contaminants.These are all critical points noted in the Miller,Hobart and Lincoln electric welding education notes available off the internet. Its all there for anyone to see.

It is incorrect to think to think that the wipers will strip corrosion of up rusty wire.  Your lube matic kleener pads  are only designed to remove those loose metallic particles and other  dust that finds its way into the wire feed enclosure while the wire is mounted on the spool and in the machine.


Three things are about to happen  and all of them detrimental to the operation of your mig:

1. You will contaminate your weld deposit if you use the dirty wire-expect porosity and loss of strength in the deposited weld bead

2. You will contaminate the cable liner

3. You will damage the contact tip and lose optimum operation of your mig.

It is false economy to go to these lengths to enable the use of some crappy  wire that needs to be chucked in the scrap bin.
On a big 15KG rolls  it is  possible to spool off 4 to 5 layers to regain a rust free zone but on the smaller ones .5 kg  or so,you  have not got a lot of layers of wire to work with.Once you get down to a clean area there is not enough usable  layers wire left to make the whole exercise practical! This sounds like what you are dealing with.

Thirty years plus of trade experience with the mig process is what the above comments are based on.
 As this thread was posted 3 weeks back I am guessing that the op  has already found out about the above points. Hopefully these comments may help someone coming along later.

Cheers

Ozwelder

[Highpower]

I agree 100% Ozwelder. In this particular case I was working on sheet metal panels that should have been scrapped anyway, so I had nothing to lose by using up some scrap wire on it as well. There was nothing critical or structural about those welds and I don't think I did any damage to my welder in the short span of the few feet of wire that I used. I certainly wouldn't make a habit of doing it. I have plenty of nice clean filler wire I could have used but this time I chose to use up some of the dirty stuff rather than bin it, fully knowing the downfalls in advance. I was willing to take the risk.   

In the end it did save me quite a bit of money however by not having to purchase replacement panels. A new liner and contact tip would have been less costly if I did destroy them. I never would have used it if I was doing the job for someone else though. Only for my own use. But again, you are correct that clean, clean, clean, is the best policy for any type of fusing metal together and your recommendations are quite sound. I appreciate you sharing your knowledge and experience.

Quote:Hopefully these comments may help someone coming along later.

I'm sure they will!