What's the coating on MIG wire?

[ashy]

Is it copper, if it is how can it go rusty?
I have bougha 5KG reel which will last me a fair while, so don't want it to go rusty. What's the best way to prevent it?

 

[irondarren]

The copper coating is only a few microns thick, so is very happy to rust through. If the mig unit is stored in a dry place there should be much trouble for a good few weeks, but if longer then i would suggest removing the reel and placing in indoors in the dry.

 

[TechnicAl]

irondarren is absolutely correct but not only is it very thin it is also not continuous. If you could look under a microscope there are areas that are not copper plated. The copper helps lubricate (being softer than steel) and it helps electrical conductivity. It also looks nice and is traditional.

 

[peterd51]

Hi,

seeing the word 'traditional' with 'Mig' made me wonder how old Mig technology actually is.

I've always thought of it as a 'new' technology.

It was around in the late '80s as I did some on the welding course but how far back does it actually go?

Regards
Peter

 

[Wozzaaah]

MIG was originally developed in the 1940's, TIG was developed around the same time. MMA (stick) welding has been around a bit longer, it was first used in the late 1800's.

 

[promusician]

Good god Wozz, have you swallowed the entire encyclopedia...i'm very impressed

 

[Wozzaaah]

NORRIE! We thought you'd deserted us after all! Hehe, my middle name is Google

 

[promusician]

NORRIE! We thought you'd deserted us after all! Hehe, my middle name is Google

nah I missed the banter, just been busy with the spit. Anyway, I better get off this thread before I get accused of hijacking it

 

[TechnicAl]

http://www.netwelding.com/History_MIG 1.htm

This states MIG welding was invented in the 1920's. I dont know if thats true or not. Im getting on a bit but not that old.

 

[Wozzaaah]

Nice article. Says it was invented in 1924 but developed into a practical system in 1949 by Airco.

 

[shenion]

Yes read that article before.

Heh, I have one of the "newer" Airco setups (1973). The MIG feeder is for spray-transfer only although the arc start does allow use on short-arc mode if you can hold the torch at a constant distance.

One thing about the coating. I have a roll of cheap Chinese MIG wire. It tarnished within days of opening it. You can see every 3' or so it gets worse. It fed terribly, probably because the diameter varied.

Probably low-quality copper coating. Never again, back to Hobart/Lincoln

 

[irondarren]

Im sure weldequip or diywelding will varify this but you can get mig wire as cheap as 9 quid per roll (or 18 dollars), if buying by the tonne pallet but it is useually chinese or indian, and probaly not that much good. The likes of hobart lincoln esab murex etc will have much tighter quality control methods

 

[ashy]

So what's the Clarke stuff like from Maxhinemart? I bought 5kg of 0.8mm mild steel for about a tenner.

 

[Drains]

TechnicAl knows of other coatings than copper on Mig wire. Hence his talk of copper being "traditional".

What they are is a secret, apparently.