309L FCAW 2G and 4G suck back

[FullfusionDND]

Hi all,

I'm having a bit of trouble with root pass suck back using .045 DW-309LP (Kobe) FCAW filler to weld 2G and 4G open groove on dissimilar metals (HSLA, high CE). Using similar parameters in the 2F and 4F I'm getting great results, as well as intermediate and cover passes on the grooves.

I'm running an Invision 456MP MIG mode @60% inductance
28.5v
350ipm
100% CO2

Is there anyone with any tips on how to eliminate the suck back? I'd normally just toubleshoot for a few hours but the material I'm using is limited in supply and quite expensive, so I need a fast track.

Thanks in advance,

FF

[M J Mauer]

Welcome to the forum.

[nfinch86]

Co2 ?

Hello & welcome !
Are you running 100% Co2 on stainless ?
I may be wrong , but adding Co2 ( carbon ) to a stainless weldment would seem counter productive ? -Yes - No ?

Norm

[FullfusionDND]

100% CO2 is pretty standard for FCAW Stainless. It's a AWS A5.22 309LT1-1/-4 meaning it can be used either with 100% CO2 or a mix of 20% CO2 balance Ar. The "L" in 309L means it's a low carbon filler (0.02%) to make up for any carbon picked up from the base metal or the shielding gas. 309LSi Solid wire stainless would use 98% Ar mixes with either CO2, O2 or sometimes hydrogen.

I seem to have decent results now using cooler parameters on the root pass, not 100% there if there are any welders more experienced with this wire than I.

FF

PS: nfinch86; I used to live in Delhi, worked at titan