contaminated welds, and a clean surface! any help?

So I shaved the handles off my four DR. When I went to weld the little patch panel in, all my welds were "popping" and were very brittle. I have the surface clean i think..I sanded down both the door and my patch then rubbed them clean with a paper towel. I took a bunch of pictures so hopefully one of you guys can lend me a hand...cool, I cant upload pics to photobucket or flikr.......but until then, why am I getting contaminated or porositic welds!! arghhh...
-thanks gang!

 

What is your gas flow set to? What is the current bottle pressure? ...And what gas are you using?

 

gas or flux??tig?stick?

 

time to refill the argon tank!

 

Mig welding indoors or outdoors?
Outdoors your gas might be blowing away instead of keeping the weld covered.

 

Along with the other suggestions, I've seen welds that were full of porosity caused by a bad ground.

 

More info is definitly needed in order for us to help you

 

I'd put money on forgetting to turn the gas on.

 

Make sure gas is flowing, and that you aren't welding in any wind that can blow your sheildeing gas away. How about the back side of the metal, how clean is that?

 

I had a guy call me to go look at some bad welds once, turned out he was using a mig with out gas and bought solid wire and not flux core.
Van

 

galvanized metal? Backside will mess you up.

 

Without knowing what type of welding, conditions etc. it is hard to say but I'll through one on the pile. I ran out of fill rod right at the end of a project recently and could not find 4130 rod in stock locally. We found a place about 45 minutes away with it in the size I wanted. Now in my area so few places use moly rod in bulk it is often starting to rust when you buy it off the shelf and needs cleaned so that can be an issue. This stuff looked spotless and laced in great but every few welds I'd hit a spot of contamination that looked like a mig weld with the gas off. It was really slowing me down having to fix the bad spots and I just could not whip the problem... While preheating a joint I ended up cooking a fill rod sitting next to it, with the rod glowing I could see a black spot inside it and with more heat about every eight inches or so on every fill rod. I cut out the spots and the problem was solved. I'm not happy about it but I'm checking my fill rods now and have found problems with others, nothing as bad as this case but if you can't find the source of your problem check the rod.

 

my tip with the nozzle off

 

the machine

 

gas

 

the machines chart

 

insides

 

the spool

 

outcome

 

another pic

 

the ground, sanded down on the other side too

 

looks like it could be a to little gas weld to me or a combination of not high enough heat, to slow of speed.,check for kinks in the regulator hose if you think gas is an issue.



i see it looks like your setting is for 20 gauge,bump up to the 18 gauge setting, and experiment until it flows in.

 

it looks like a gas flow problem, but something else I would check..the insides of door panels were often sprayed with a heavy coat of tar like stuff to sound deaden them from new..and that stuff would contaminate a weld quicker than anything. have you cleaned the inside area behind the hole??

 

I have not cleaned the area behind! i dont even know how to go about doing that!!

Eddie- what makes you say that my settings are for 20 gauge? I'm still trying to figure out this machine..

Thanks everybody!

 

Pirosity!!!-----Crank up the flow meter to 20----Play with feed speed---Good ground.

 

Still figuring out the machine? Got clean sheet metal around? Set it up so you're running good on the clean stuff then go back to your door and see what happens... Test welds will save your life.

 

x2 on checkin out the back of that door panel. or even the inside rim of the doorhandle/keyhole may still have some rust/corrosion still left over.

but lookin at it again...that kinda does look like a gas issue...welding outdoor in the wind or no gas at all.

 

Not sure how hot temps are where you live yet but I've forgotten to turn off the shop fan a time or two when I'm welding. That'll piss ya off!

Honestly, if it's popping and spattering, sounds like a ground problem. Cleaning your ground clamp once in a while is a must, give it a try...

 

x2 on dialing in the machine/gas flow & practicing on clean scrap of similar or exact thickness.

 

You may want to try millerwelds.com if the real good advice already given above doesn't work. Although these guys seem to have really nailed it! Good luck!