"Worm Tracks" on top of weld bead when using Lincoln 71M dual-shield flux core

[Baxter]

I'm new to using dual-shield and so far I really like it, with one minor exception. I'm using lincoln 71M .035" DCEP using a Miller 250X Ar/CO2 mix@ 30 cfh. Overall I am pleased with results. I am however getting small, randomly appearing Jalapeno-shaped craters in the weld bead about 1/8" long. I've found increasing the gas flow up to 45 cfh significantly reduces the number of craters, but it doesn't totally eliminate the problem. The weld itself is sound, with no visible porosity - these are small surface imperfections. Has anyone else experienced this?

[86k10]

Try increasing your stick out (should be around 3/4"-1") and or lower the voltage. What are your settings?

[HT2-4956]

http://www.lincolnelectric.com/en-us...ess-welds.aspx

[TimmyTIG]

I'm new to using dual-shield and so far I really like it, with one minor exception. I'm using lincoln 71M .035" DCEP using a Miller 250X Ar/CO2 mix@ 30 cfh. Overall I am pleased with results. I am however getting small, randomly appearing Jalapeno-shaped craters in the weld bead about 1/8" long. I've found increasing the gas flow up to 45 cfh significantly reduces the number of craters, but it doesn't totally eliminate the problem. The weld itself is sound, with no visible porosity - these are small surface imperfections. Has anyone else experienced this?

Yes, all the time. Moisture in the wire flux seems to be the main culprit.
On the first 36 inch weld I did the sub arc fill and cap on last weekend, I had some chicken track looking marks. They were only on the surface. I had used a half full bag of flux that was in the heated and supposedly de-humidified rod room. The flux was in a closed and rubber banded plastic bag, but still got wet somehow.
I dumped that flux and got a brand new bag and the chicken tracks went away on the second weld.

[ferrret3238]

I was getting some of that also when I ran some dualshield on a snowplow I was working on. It was a used roll from ebay and there was a little rust on the outside of the spool. I cut off a few layers and it still did it. I figured it was just moisture in the wire so I took the wire and set it on some aluminum foil in a baking pan in the oven. I let the wire cook at 225 for around a hour to boil out any moisture in the wire and it ran a lot better. I stuck it in a bag when I was done welding but I will probably just bake it again before I have to use it again. It was Lincoln Ultracore 71A85 .045. It ran very nice welds.

[HT2-4956]

ferret,

In your case, when you get gas marks it'd probably be more accurate to call them ferret tracks. Eh?

[DerekV]

http://www.lincolnelectric.com/en-us...ess-welds.aspx

WOW - thank you for sharing this. I have the same issues as the OP and this literally covers everything. Lincoln has excellent educational articles/documents. Again, thank you.

[A_DAB_will_do]

I was getting some of that also when I ran some dualshield on a snowplow I was working on. It was a used roll from ebay and there was a little rust on the outside of the spool. I cut off a few layers and it still did it. I figured it was just moisture in the wire so I took the wire and set it on some aluminum foil in a baking pan in the oven. I let the wire cook at 225 for around a hour to boil out any moisture in the wire and it ran a lot better. I stuck it in a bag when I was done welding but I will probably just bake it again before I have to use it again. It was Lincoln Ultracore 71A85 .045. It ran very nice welds.

Baking can help with moisture related problems. But be aware that the wire may have a feeding lubricant on surface that's applied when the manufacturer puts the wire on the spool. IF you bake at too high a temperature, that lube can be affected by the heat; or vaporized and lost. The wire may have problems with feeding through the gun if the lube isn't there or altered by heat.

Check with the manufacturer for guidance on baking flux cored wire, and remember if some is good, more is not always better.

[Baxter]

I've been varying the wire feed speed and voltage a little to see if that helps. I started out at 310 ipm with 22.5v . I havent tried lower voltage than that. I will continue to monkey around a bit. Overall I'm very pleased with the 71M. It really has good penetration and cleans up easier than 7018 stick, with comparable penetration. The link posted by HT2-4956 (http://www.lincolnelectric.com/en-us...ess-welds.aspx) really helped. Thanks.

[ferrret3238]

I was nervous about burning out the flux in it at first but decided to try baking it anyway. It was what caterpillar spec'd out for attaching the carriage to attachments so I decided to try it. I thought if I kept the heat low and just above boiling it wouldn't hurt the flux or the coating and it was rusty so maybe it wasn't even coated or just worn off? It is a 44 lb spool that I got for $45 so if it didn't work I was prepared to just throw the roll in the garbage. Even after all the prep work it would still leave "ferret" tracks lol!! if I tried to do a weave or move the gun around too much.

[TimmyTIG]

Those tracks are just on the surface, you can grind them off, if they bother you.

I would be more worried about the rusty wire clogging up my liner.

[HT2-4956]

I was nervous about burning out the flux in it at first but decided to try baking it anyway. It was what caterpillar spec'd out for attaching the carriage to attachments so I decided to try it. I thought if I kept the heat low and just above boiling it wouldn't hurt the flux or the coating and it was rusty so maybe it wasn't even coated or just worn off? It is a 44 lb spool that I got for $45 so if it didn't work I was prepared to just throw the roll in the garbage. Even after all the prep work it would still leave "ferret" tracks lol!! if I tried to do a weave or move the gun around too much.

ferrret3238,

If I were you I think I'd be sorely tempted to go have a rubber stamp made of a Ferret paw print. And then with the aid of an ink pad it probably wouldn't take me long to have "Ferret Tracks" on all kinds of stuff as a way to mark territory, property or the things I built / welded on.

For safeties sake though you'd have to exercise some restraint. For instance, it probably wouldn't be a good idea if any of your friends or coworkers started finding "Ferret Tracks" on any of their wives or girl friends.

[HT2-4956]

Baking can help with moisture related problems. But be aware that the wire may have a feeding lubricant on surface that's applied when the manufacturer puts the wire on the spool. IF you bake at too high a temperature, that lube can be affected by the heat; or vaporized and lost. The wire may have problems with feeding through the gun if the lube isn't there or altered by heat.

Check with the manufacturer for guidance on baking flux cored wire, and remember if some is good, more is not always better.

More good info. I know you helped me out quite a bit a couple years back with info concerning that "dry lubricant". The big thing you helped me understand at the time that really helped was how that if you used a wire wiper you'd lose any of the benefit that dry lube gave you toward smooth feeding.

Based on our conversations I'm pretty sure that the light grey powder you see on the floor of this feeder unit is that dry lubricant you speak of that the wire wiper that was on there knock off. And I'd have to guess that the darker stuff you see piled up around it is more of that dry lube that's been laying there long enough to absorb moisture from the air.

In general this picture makes for a pretty good poster showing what a piss poor program of wire feeder maintenance ends up looking like.

[Baxter]

310 ipm 22v. Its a brand new spool of Lincoln 71M .035 wire from my local welding supplier, who I've been dealing with for many years. I think the stickout might be a part of it too. I'll also try a different contact tip when i get going with it again.