1mm Sheet Query

[Barking Mat]

Mig Beginnerish, longtime lurker.

I finally got hold of some thin steel, 1mm and having got quite happy with arc and mig on thickish (3mm upwards) I thought I try migging some thin stuff.

What's going on here? I don't think its burn through (there are no holes). Too much penetration? Too hot?

And whats with the orange stuff I often get on my welds, like you can see.

Thanks in advance. Mat

 

[wyn]

That looks like it was sitting on something, the weld has penetrated through and just picked up a bit of rubbish from the surface it was sitting on.

 

[Barking Mat]

Noo, it was tacked vertical, after both sides had been cleaned up, so couldn't have touched anything, could it be a tiny quantity of paint left, though it looks like the back of the weld wanted to melt?

 

[wyn]

Maybe as the paint is ground off the surface a bit is deposited on the 1mm edge by the action of the cleaning/grinding disc.

 

[bigbadbugga]

I get the orange stuff on lots of my welds too, I always assumed it was the remains of the copper coating on the mig wire.

 

[greyshirtguy]

I always thought it was the silicon content in my MIG wire...
The wire I use (ER70S-6) is very common and it has some silicon to act as a deoxidiser for "less then perfectly clean" metals.....

 

[Iain Westland]

machine, wire size, gas and settings? would have liked the join between the two sheets to be welded rather than visible. the back of the weld is showing penetration, I assume both pieces show the same.

was this pulsed or in one long weld?

nice

iain

 

[Bsmith]

I always thought it was the silicon content in my MIG wire...
The wire I use (ER70S-6) is very common and it has some silicon to act as a deoxidiser for "less then perfectly clean" metals.....

Yep its silicon, orange/green spots very oftens show up on mig welds, nothing wrong there. The orange soot residue at the sides of the weld is left behind after the arc, a lot of this would mean lack of shielding gas, yours is ok.

Your weld is fine except a bit high in the middle, just need a bit less wire feed I think..

 

[Barking Mat]

Morning, and thanks for the feedback.

Its a 3ph Migatronic 325 'compact'(?), using a co2 argon mix, the wire is .6mm and copper coloured (and old), can't be any more specific as that's the roll which it came with.

Its not pulsed, it one long weld, tacked before. The bit where it's not touching on the back must be somewhere in the region of 0.1mm or less as the edge you can see is 1mm. The macro setting on this cameras not amazing. Settings 2 wirespeed 2. Power setting 1 produces logs, setting 3 is good but has a tendency to burn holes.

So that stuff on the backs OK? And that's acceptable? Here comes the ashpan for the rayburn today. Thanks.