Thread: Imig200 flux core welding questions - Everlast Welders

I have a imig200 and some lincoln flux core wire. I'm looking for some pointers since the welds ive been trying dont look very good and have been coming out really black instead of having a brownish coating I can scrape off. Ive been welding 1" square tube x.065 wall.

Jody for wt&t said in one of his videos that flux core should be welded dcen. Ive tried dcep and dcen and im not seeing a big difference. Im getting alot of bbs and the weld is getting real black.

What kind of voltage and wire speed would you run for this material?

If I switch to solid wire do I have to use co2/c25 or can I use straight argon?

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It says right on the spool DCEN. With self shielded flux core wires you have to read the manufacturer's specs. Some wires run on DCEP, like NS-3M, and NR-305. Several things can be wrong here. First you really need serrated drive rolls for flux core wire. You may get away with running .030� flux core wire through a Mig gun, and maybe even up to .045�. But there are dedicated flux core gun. I've always had good luck with Lincoln's K-126 guns. The problem with flux core-ss wire is it's very stiff, and when it get hot it expands, Mig guns are very flexible, sometimes these two are just not a good match. Try to keep the gun as straight as you can at all times.
I've run tons of NR-211, then after the Northridge earthquake in California Lincoln came out with the MP. I like Lincoln's NR-212, better. But I believe Hobart's Fabshield 21-B is better than both 211, and 212.

The problem is more than likely the fact that I dont have flux core drive rolls. What exactly does the drive roll do to the wire that makes it different from a regular drive roller? The wire feeds fine... does it puncture the wire so that the flux can flow out? Sorry im a noob when it comes to using flux core wire and a noob at stick welding.

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the serated drive rolls grab the wire requiring less pressure than would be needed with the regular grooved rolls for solid wire. With Solid wire, the pressure does not deform the wire, but if you used flux core wire with these rolls, they would crush / deform the wire and cause feeding issues. The serated rollers can grap the more delicate flux cored wires requring less compression force. Test the wire feeding using the methods commonly described in the manuals, that is try feeding wire at a 45 degree angle against a non conductive surface (wood) and it should feed smoothly, into a curl. Adjust the feed rollers untill there is just enough pressure, that the wire feeds continuoulsy without stalling.

Also, first try running some beads on 1/8" clean steel, and you want to run the recommended settings in your machine table/cover. Run a drag bead, and adjust wire feed until you get a cosistent arc, no sputtering and it will be a steady sizzle sound (like bacon). No gas with this wire.

I only have the regular drive rollers and I've adjusted the feed rate and it feeds fine. I still get a black nasty weld... It's a good solid weld that you couldn't break, but it seems like the weld is contaminated because the weld bead is all black. If I have time tomorrow I will run a bead on some super clean metal and possibly shoot a video. I'm not the greatest MIG welder with the limited experience I have but I know that it could look alot better than it does.

My experience with Flux Core is your metals being welded have to be really clean. Grind or sand the areas being welded. Mil scale, rust, dirt or other contamination that you can occasionally get away with using gas mig or stick will wreak havoc with flux core. I'm on my 3rd 10# roll of Lincoln NR211 and still occasionally have bad runs with porosity, nasty looking beads, or the black color that you are referring to. As a rule the flux on a good weld will be a white/tan color and 90% of it comes off with a wire brush.