Using MIG as a cutter?

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I made a project in a class where I cut leaves out of thin sheet steel with a torch for a piece of garden art.  After installing the piece, I found I need one more leaf.   I don't own a torch, so I was thinking that since I have accidentally blasted through steel while welding, maybe I could use the MIG to cut out the leaf. A rough edge on the finished piece is okay. I don't recall the thickness of the sheet of steel off hand - maybe 1/16".  I'm guessing I crank up the voltage and turn down the wire speed. Will this wreck my welder?
Reply:Naw, it won't wreck your welder.  Might toast a tip if your not careful. The outcome might be a bit ugly though.Common sense in an uncommon degree is what the world calls wisdom.
Reply:Dont guess that you have a stick welder crank a 6011 up all the way and go to town. If not cant see how it would hurt your mig, Agree with brain might be rough on your tips.no you cant fix it with a hot pass.BORN TO LOSE, LIVE TO WIN.
Reply:I think I would tun the wire and the V way up and try it.www.urkafarms.com
Reply:Sberry, what's your thinking on turning up the wire speed?
Reply:My thought is: with a slow wire speed the wire will touch, burn back, touch, burn back, repeat over and over. You need to keep the wire in contact (or close to  ) to keep the arc going. Too much speed might create problems for trying to cut as well. I know you in a pinch but I think this is a real hard way to try and do this.MillerMatic 175Thermal Dynamics Drag-Gun PlasmaAirco Bumblebee AC/DC SMAWVictor Super-Range II oxy/act
Reply:Originally posted by WillyWeld Sberry, what's your thinking on turning up the wire speed?
Reply:You did good, cant say it better than that.www.urkafarms.com
Reply:Thanks for the explanations.  I think I get it.   I'll give it a shot and let you know how it goes.  Sounds like it won't be pretty.....
Reply:Originally posted by cutter I'll take a shot at that:  not only will you probably melt the wire into your tip & weld it, you need to also remember that the voltage switch controls your voltage & the wire speed controls the amperage.  I.E. , the faster the speed the higher the amps.  You will need high amps to cut, I should think.cutter
Reply:I'm betting the wire blows through the metal and the arc goes out. It might work if you pulse the gun. Like a running tack weld. If the wire feed is high enough to cut then the hole it blows will be too big to short the wire. That's the way MIG short arc works. The wire continuously shorts, melts back, shorts, melts back. When the base metal blows there isn't anything to short. But it's an interesting concept. Waiting with baited breath.
Reply:Well it wasn't pretty but it didn't look that much worse than when I cut the original leaves with a torch.  The picture shows the small leaf I cut with the MIG and the big leaf I cut with the torch.  I cranked both the voltage and wire speed to max.  I angled the tip back maybe 30 degrees and "pushed" the tip along the metal.  Sometimes it cut nice like a plasma cutter, sometimes it blasted through and lost the arc, and sometimes it laid in a nice tack.  I attribute all this to speed of the tip and making curved lines.   I ended up having to free hand the cut despite drawing chalk lines because when the arc is piercing through the metal it doesn't light up the surface, so I couldn't see my lines.  It worked in a pinch but I'm not sure I'd do it again.  Thanks for the advice. Attached Images
Reply:By the way, I needed the small leaf to add to this garden art ring o' leaves to make it "weather vane" in the wind.  It was so balanced that , when allowed to spin, it always faced flat to the wind and it was eventually going to bend.  I added the tail so hopefully it will now act like a weather vane. Attached Images
Reply:They do look like Burr Oak leaves. Nice ring.
Reply:Nice project!!!Ron ShopFloorTalk Millermatic 350P, M-25, M-40 gunsDynasty 300DX, Coolmate 3, Crafter CS-310 TorchTrailblazer 302, 12RC, WC-2430A spoolgunSpectrum 2050Thermal Arc Plasma Welder PS-3000/WC-100B
Reply:California Valley Oak is what I was going for.  : )
Reply:Looks really cool, Willy.   I like it.Just for reference and grins, why don't you experiment some more using different settings, like slowing down the wirespeed & see what happens?
Reply:Cool garden ornament! My yard Nazi would love it.  In the best tradition of the Greeks and Romans, maybe you could make some more to plant on the heads of local Marathon winners.
Reply:Hey Cutter, don't encourage me.  Actually I may try it again.  I did try turning down the wire speed when I was trying to blow away some inadvertant weld blobs and it was hard to tell if it helped.  Playing around some more on clean metal would probably be an interesting exercise.Ol Pilot, those would be some tough marathoners wearing a steel crown o' leaves.