Welding Help

[Mark One]

I'm doing some repair work on my MK1. It's the first time I've had to weld anything this thin (0.9mm).

I've got a pub gas CO2 bottle which is great for the 3mm plate that I've done before. I've got a SIP MigMate 105 which was recommended in a group test, but I find to be a load of sh1te.

I'm having loads of trouble with poppy, spattery weld. If it ever eventually settles down, it blows holes very very quickly.
I'm wondering wether pure CO2 just isn't suitable for this job. Will i Need a 75% argon?

 

[sideways danny]

-prep the area better
-get some scrap and practice until you have settings you can work with.
-Don't expect to be able to do long runs of weld on shin sheet metal, you have to do fairly short burst and stitch it, or move a lot quicker than you think

 

[Fred@BTM]

yeah just keep tack, tack, tack, tack

keeps the area from getting too hot

what wire speed are you on? what settings does the welder have?

 

[Mark One]

It's one of these. Three swtiches Low-Medium, Max, High-Low. Then wire control dial on the left. I'm going to try pushing it up a little and going in small tacks. Cheers Guys.

 

[Mark One]

-prep the area better
-get some scrap and practice until you have settings you can work with.
-Don't expect to be able to do long runs of weld on shin sheet metal, you have to do fairly short burst and stitch it, or move a lot quicker than you think

yeah just keep tack, tack, tack, tack

keeps the area from getting too hot

what wire speed are you on? what settings does the welder have?

Instant results. Don't know why this didn't cross my mind sooner.
Cheers

 

[sideways danny]

start on low everything and increase wire speed gradually, you should be able to get a weld without spitting and farting, but most likely without much penetration. step up to the next power stage, and do the same with wire speed, that'll most likely be as powerful as you can go with that material.

The other thing is, are you trying to butt weld, or have you overlapped?

edit, LOL, you posted as i was typing

 

[Fred@BTM]

medium setting, low, 70% wire speed, winner

 

[Mark One]

I'm butt welding. I was just getting far too much heat build and pushing holes through, then going to try to reduce amps and just getting zero penetration and pop, pop, pop, pop.

It still needs a touch of tweaking to get perfect, but I can now get a nice butt weld between two plates, albeit with a bit more filler metal than is necessary. I've gotten through quite a lot of sheet now just trying weld settings!

 

[Gouldy]

depending on your amps / wire speed etc.

i start welding and count to 3 then let off and watch the weld cool slightly, only a little though. then go back in and count to 3 again.

its a basic method but if the machine is set up right this technique works a treat, its what i do when root welding.