newbie mig weld question

[rick-l]

Let me get this straight. (my phone camera dosen't cut it)

I'm trying to weld 1/8" steel plate, butt weld, .023 wire C25 gas MM175. No bevel, no gap, supposed to be cold finish 1018.

Followed the recommendations under the lid. If I go slow I get a huge bead (1/8" high) with maybe 1/16" penetration. If I go faster I get a flatter 1/16" bead with little penetration.

What do I do now? Logically it would seem I want a bigger puddle with less filler. If I just crank the voltage the wire burns back to the tip. Seems like more wire (more current?) would just add filler.

Also if I look at the edge of the bead under a microscope there is a hard milky colored substance between the bead and the metal plate. If I chip it off with a pin it looks the metal is fused under there but I can't tell. The edge of big bead meets the plate at a 90 degree angle which dosen't seem like what I want. Is this what everyone calls wetting the edge? What is that hard whitish brown stuff that chips off?

This isn't for any particular project I'm just trying to figure out what is going on so when it counts I'll know what to do. What would you do next if this joint required a quality weld? I can play some more but want to make sure I'm gong in the right direction.

[tigman250]

pics would be good but it sounds like you can either adjust your voltage up or wire speed down this will get you a flatter wider bead, the door specs are just for refrence they will get you close but you as a welder need to fine tune for optimal performance. it sounds as if you are running too cold, try moving to the 3/16 settings and dial back your feed to get the results you want. 1/8" matl. is probably at the upper limits of .023 wire. at the higher voltages you will get the "wetting" action you are looking for but it does have it's drawbacks, you will get more warpage at a higher heat level. but if your welds are meeting the work at a 90 degree angle you are definatly not hot enough. rember to adjust a little at a time if you adjust a quarter turn at a time you will never get the results you desire.

[Coalsmoke]

"Captain, I think she might need more heat!"

Without pics, its hard to say, pics would be good.

[stinkinlincoln]

I doubt you'll ever get full penetration and an attractive bead without a gap or bevel. If I wanted the best bead appearance and the easiest weld I would bevel about half way through. If I wanted to get it done. I would gap the plates about 1/16 through 1/8. Like tigman says more voltage= flatter bead. If you cant or dont want to gap or bevel just crank her up and don't expect beautiful welds. Sounds like the crap on/around the bead is probably silica, common and not a problem itself, but having it where you described it to be points toward too cold of a weld. I mig 1/8" everyday at work with .035 wire and we would never buttweld without bevel or gap. Good luck

[KB Fabrications]

<snip>...........................................w e would never buttweld without bevel or gap. Good luck

Great advice and if you want any stuctural integrity to your welds you'll follow it. If you don't bevel or gap a butt weld the metal has no place to go but to move around on the surface with little or no penetration as well as incomplete fusion. Proper joint prep is also critical to your end result asthetics. I would worry less about how it looks at first and concentrate on proper process first. As others have stated, pictures are a big help. Good luck.

[Paul Seaman]

I would start with a weave like a z and on the sides count 1-2 then move quickly accorss the center and 1-2 do this for a full bead and see if it flattens out and achieves better penetration.

Peace,


ps. use a backhand gun position{ drag the weld behind the gun itshould help}

[precisionworks]

On thick material like 1/8", .035 is all I use. Recently ran three butt welds, each one 80" long, joining 1/8" treadplate sheets. Gapped each one about 1/16", flat position, 21.5 volts, 200 IPM wirespeed.

Hot enough that if you blink or pause for for an instant, you achieve 101% penetration. Went under the plates to weld the overhead tacks and the bottom of the butt weldments were that pretty gray color, nearly 100% penetrated.

An easy way to find the hottest practical setting is to increase volts & wirespeed until you start burning through, then back off by 10% to 15%. Burn it deep

[cswartz3]

These dudes are right, get a bevel or gap in there, crank the juice and wire, and start making your own door-panel setting guide. what kind of wire are you running also? ER70s3, s6? s=silica and comes from the copper colored coating on the wire that serves to protect the wire from corrosion and as I've been told, helps in puddle formation (wetting-out) characteristics, and helps protect the bead as it cools back to ambient temp, after the gun and shielding gas have moved away, like the flux coating on stick. Generally, this glassy substance will break away with minimal effort, agood wire wheel on a grinder will get the stuborn stuff. Flux-cored wire will leave more of this scale, and is a bigger pain for beginners( at least it was to me, and every one I know) to master, as well as, making nasty fumes. Galvenized mat'l, when welded will produce highly toxic fumes, a fuzzy white/yellow chalky substance(the fried zinc) that is a mess to get rid of, not to mention again the extreme health risk. Did you use any kind of anti-spatter spray prior to welding? I'seen this stuff cause varience in power settings, minimal though, a volt or 2, and 5-10 ipm ,along with the scale changeing appearence/presence. What did you clean the raw mat'l with? residue from some degreasers can have similar effects. As for wire diameter, .023 is ok for lots of stuff; I use it on 1/4 1018 all the time; 3/8, 1/2 are just a bit too much, I've tacked this thick without much problem, big bevels of course. .035 wire if you've got the power and the tips ect. to use is a much better gig.