Another newbie! Suggestions/Critiques? Pictures inside...

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Hiya folks!  I've been lurking on these forums for a bit now, there's some fantastic information here.  I thought I'd pick the brains of you pros and try to glean a few pointers!I've been MIG welding for a few weekends now, I plan to eventually try and repair rust damage on my autocross car and have been practicing as much as possible in preparation.  I bought a Lincoln Weldpak 3200HD and an R of C25 gas.  The tank is proving to be smaller than I thought...  I was bitten by the one rule I read here that I didn't follow, to buy a bigger tank than you think you'll need.I did a little flux core welding before I attached the tank, here are a few pictures of my very first weld ever, done with .035 flux core on some old pieces of bedframe.I soon switched to .025 solid wire and C25, and started practicing with 16ga. sheetmetal, similar to the type I'd be encountering on the car.  It didn't go as well at first, hehe.  A little more practice though and I could at least lay some decent beads.I actually have trouble laying good beads on butt and lap joints, so far I find fillet welds to be easiest.  I'm thinking I may just need more practice, but any help in the technique department would be much appreciated!Here's a shot of an early fillet joint, along with a butt joint at the bottom where I was playing with settings and was way too hot:And here's a better fillet, after a few more tries:I noticed that I seem to have alot more spatter than most MIG welds I see.  Would that be too much voltage, or is the amount shown acceptable?I also tried going back to the heavy bedframe scrap, but found the .025 wire to be too small to get any penetration.While I could get some pretty beads, they were superficial and didn't penetrate.  So I turned the welder up to full power (D on  Voltage and 10 on wire feed), and just held the gun in place for about 10 seconds for each of these:No penetration at all, the wire just pooled up and wouldn't penetrate.  Looks like I need to go back to .035 wire to get the job done on that kind of thickness.Also, I've noticed that soon after I release the trigger on the gun, if I touch the wire back to the metal soon after it will spark, like there's still a circuit with small bit of current left.  Is this a problem with my welder not completely breaking the connection, or is this normal?Another thing I noticed is that I seem to have a brown discoloration on some of my welds, deposited in the direction the gun is pointing.  It wipes right off, but without direct instrustion I'm wondering if this is normal or a symptom of something I'm doing wrong, like not enough gas flow, drafts, etc.  The only shot I have is on some crappy tacks and other welds I'm embarrased to show, but oh well!So there you have it!  My first foray into welding.  I was wondering if anyone could spot any glaring problems with anything.  I did notice that I seem to have a problem with cratering in my tacks and spot welds, even in those large blobs on the bedframe.  Any help with that, and with technique in general would be great.Sorry for so many questions, but any help, ideas, techniques or criticisms would be greatly appreciated!  Thanks again! -Paul
Reply:Soot?  Usually means incomplete shielding gas coverage, some causes are drafts, nozzle obstructions (spatter or holding the nozzle too close to the work), or even too much gas flow (it sucks in air or just blows right past the weld area).The WeldPak-3200HD really doesn't have the amperage to run 0.035 solid wire.  Run it with 0.025 or 0.030 solid wire, or 0.035 flux-core.Excessive spatter in GMAW is usually too little or too much voltage, excessive stick-out (maintain 3/8 to 1/2 inch ESO), dirty metal or wire, and CO2 spatters more than plain argon.  Oh, and make sure that the unit is set to DC-EP for GMAW/MIG (FCAW is set to DC-EN).Check the chart inside the wire spool door or in the instructions for the WeldPak-3200HD (page 32 of 48) and notice that the machine's capabilities with GMAW/MIG stop at 14 gauge mild steel.  Thicker mild steel with that unit needs 0.035 flux-core.
Reply:As one newbie to another. I included a picture of one of my welds.I'm actually building the folding picnic table in Lincoln's Arc Welded Projects Vol 1. If anybody wants to build it, watch the measurements. Some of them are very hard to figure out.I also have the HD 3200 and I'm finding that 1/8" mild steel is pretty much the limit with this machine and the metal must be very clean. I run it at D7 with .025 wire and 20 cfs Argon/CO2. I clean all the joints with a wire wheel on the grinder and then I wipe the joint down with alcohol. The cleaning has really inproved the quality with solid wire.Someone had mentioned that the brown powdery residue was a result of improper gas flow. I guess I just assumed it was from the silicon they put in the mig wire.I see a little bit of spatter and brown residue on my weld. So is this weld ok or do I need to tweak things a bit?Sorry, don't mean to hijack your thread, but I'm curious now that I've seen your pics and am wondering if perhaps my welds need a little work.Thanks,James Attached Images
Reply:noobies should register at the intro forum before posting tons of pics for us to examine..... i've examined them...welcome aboard anyway...isnt welding fun??...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by zapsternoobies should register at the intro forum before posting tons of pics for us to examine..... i've examined them...welcome aboard anyway...isnt welding fun??...zap!
Reply:Practice guys. Time with the torch = experience which (usually) = better welds. If you can have a good welder's tuition for an hour or two that'll help. Good luck.
Reply:The brown soot is usually just a residue from the agents in the solid wire and possibly a few impurities too. Notice it's about the same color as the glass slag left on or around your weld bead area. Black soot can be marginal gas coverage but much of the time it's a voltage issue. Some clues to watch for. Dark soot, ridge in the bead, = voltage may be a little low. Big spatter, bead too flat = voltage may be a little high. Of course you need to play with the wire speed for practice purposes too.  A little silvery spatter/spray is about right. Most of the spatter problems just sort of go away with time. One thing to consider is the door charts. They were developed by folks who know how to weld, so they can't be that far off. But the joint configuration plays a huge role. A "T" joint or fillet can take a lot more heat that a butt with a gap of the same thickness. Knowing that you'll need to vary the settings up or down from the charts 1/8" reccomendation.
Reply:Originally Posted by DarkhandHiya folks!  I've been lurking on these forums for a bit now, there's some fantastic information here.  I thought I'd pick the brains of you pros and try to glean a few pointers!I've been MIG welding for a few weekends now, I plan to eventually try and repair rust damage on my autocross car and have been practicing as much as possible in preparation.  I bought a Lincoln Weldpak 3200HD and an R of C25 gas. I soon switched to .025 solid wire and C25, and started practicing with 16ga. sheetmetal, similar to the type I'd be encountering on the car.  It didn't go as well at first, hehe.  A little more practice though and I could at least lay some decent beads.I actually have trouble laying good beads on butt and lap joints, so far I find fillet welds to be easiest.  I'm thinking I may just need more practice, but any help in the technique department would be much appreciated!Here's a shot of an early fillet joint, along with a butt joint at the bottom where I was playing with settings and was way too hot:And here's a better fillet, after a few more tries:I noticed that I seem to have alot more spatter than most MIG welds I see.  Would that be too much voltage, or is the amount shown acceptable?I also tried going back to the heavy bedframe scrap, but found the .025 wire to be too small to get any penetration.While I could get some pretty beads, they were superficial and didn't penetrate.  So I turned the welder up to full power (D on  Voltage and 10 on wire feed), and just held the gun in place for about 10 seconds for each of these:No penetration at all, the wire just pooled up and wouldn't penetrate.  Looks like I need to go back to .035 wire to get the job done on that kind of thickness.Also, I've noticed that soon after I release the trigger on the gun, if I touch the wire back to the metal soon after it will spark, like there's still a circuit with small bit of current left.  Is this a problem with my welder not completely breaking the connection, or is this normal?Another thing I noticed is that I seem to have a brown discoloration on some of my welds, deposited in the direction the gun is pointing.  It wipes right off, but without direct instrustion I'm wondering if this is normal or a symptom of something I'm doing wrong, like not enough gas flow, drafts, etc.  The only shot I have is on some crappy tacks and other welds I'm embarrased to show, but oh well!So there you have it!  My first foray into welding.  I was wondering if anyone could spot any glaring problems with anything.  I did notice that I seem to have a problem with cratering in my tacks and spot welds, even in those large blobs on the bedframe.  Any help with that, and with technique in general would be great.Sorry for so many questions, but any help, ideas, techniques or criticisms would be greatly appreciated!  Thanks again! -Paul
Reply:As has been suggested previously, try slowing down and holding the wire in the puddle a bit longer.  Also, to help slowing your forward progress with the bead, experiment with a side to side weave pattern.  This will keep the arc in the puddle a bit longer, resulting in better penetration.
Reply:The spark you see when you re-touch the wire to the metal is NORMAL.  If I remember correctly, it is caused by the filter capacitors in the output stages of the welder.
Reply:an S pattern will help on the thicker stuf. summer is here, plant a tree for mother earth. if you dont have time or space, sponcer some one else to plant one for you.feel free to shoot me a PM or e-mail me at [email][email protected] i got lots of time.
Reply:I think all you need is some time.  Just watch your puddle, watch everything flow togather.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:Originally Posted by slamdvwThe spark you see when you re-touch the wire to the metal is NORMAL.  If I remember correctly, it is caused by the filter capacitors in the output stages of the welder.