fluxcore vs solid wire

Why is it you can weld thicker metal with flux core than with solid mig wire? I have one of the portable Lincoln 170 amp mig welders & have to change from solid to fluxcore when I need to weld thick steel plate.

[cutter]

Originally Posted by metalneck78

Why is it you can weld thicker metal with flux core than with solid mig wire? I have one of the portable Lincoln 170 amp mig welders & have to change from solid to fluxcore when I need to weld thick steel plate.

Mostly because the shielding gas cools the metal at the same time the arc is trying to melt it.

[X-ray]

Dont know if this will help or confuse, but it will give you something to read: http://www.weldreality.com/discussio...asp?PostID=241

Looking foward to what the welding hoodlums have to say about this solid vs. flux core topic

Oops, danga your fast Cutter

[Franz]

Fluxcore and MIG are actually different processes done by the same machine.
Fluxcore is very similar to stick, with the difference being the flux is inside the electrode rather than on the outside of the electrode as it is in stick. The flux allows the wire to act differently than wire within a gas shield.
Also, there is definitely a lot less depositable metal in a foot of .035 fluxcore than there is in a foot of .035 solid wire. Less metal means the same amount of electrical power in the arc gives you more heat. More heat means you can deposit more metal, and dig deeper, even if it takes more feet of wire to do it.

[DDA52]

Didn't I read somewhere, not sure where, that flux core was closer to spray transfer with solid wire than short circuit?? Or did I make the coffee too strong this morning?

Thanks for the help, think I sorta understand how it works now. Looks like I need a bigger machine, or keep switching out my wire. Makes sence to me now why I have to weld much slower when using fluxcore.

[JTMcC.]

Current density (the ratio of current to the cross sectional area of the wire), the resistance heating of the relative (compared to solid wire) small/thin wire results in higher deposition rate. And the small cross section current path makes the arc stream assume a narrower shape, that results in more penetration.

JTMcC.

[fatfrank]

Kind of on the same topic. I have just been running flux core in my HH175 lately because I can make solid welds without grinding all the mill scale off my joints. If I do get a more powerful mig will I be able to burn through mill scale on new metal with solid wire? If I won't be able to, I probly won't upgrade, I'll just keep running fluxcore in my HH175

[Franz]

Originally Posted by fatfrank

Kind of on the same topic. I have just been running flux core in my HH175 lately because I can make solid welds without grinding all the mill scale off my joints. If I do get a more powerful mig will I be able to burn through mill scale on new metal with solid wire? If I won't be able to, I probly won't upgrade, I'll just keep running fluxcore in my HH175

Frank, when you get a welder with higher capacity, you'll be amazed what you can burn thru. Of course, you'll need to modify your techniques, or learn to dial it back and fill holes.

[fatfrank]

Originally Posted by Franz

Of course, you'll need to modify your techniques, or learn to dial it back and fill holes.

Franz............you trying to say something about my fit-up techniques?