i posted a similar question in the longe but figured it ould fit better here.

i picked up a flux cored welder friday to weld my exhaust up and was curious as to how strong the welds are for other things such as weld in suspension mods, subframe connectors and such.

curt

 

Provided you weld it properly with the right temp setting they're just as strong as any other mild steel wire weld. Difference with the flux core is it does not need an inert gas to weld properly, think of it like an old arc welder when using flux core wire. The welds will not be as pretty and you'll have alot of spatter then if you had gas and steel wire.

It also burns quite a bit hotter as well, so becareful as the exhaust is pretty thin.

 

Flux core = very ugly welds.

 

you can still stack nickels with it, but the spatter leaves much to be desired. They do make an aresol can of anti-spatter spray, much like a can of spray paint, and you spray it on everything you dont want spatter to stick to. worked very well when we welded aluminum to keep it from streaking/buring material not directly being welded, but have'nt tried it on flux so cant say with certainty.

takes longer for it to get inital burn into metal and a little more finesse puddling, but you can make the weld itself look pretty...cant say too much for the area around the weld though

 

yeah, i used the welder on a few scrap peices and there is plenty of splatter. i was told to get the wire speed just right and use the aresol spray to avoid excessive splatter.

 

You can also get a little more penetration with a smaller MIG as well, the duty cycle is'nt as long, but you load up some .035 flux core in a similair welder and you can burn a little deeper into thicker material than using steel wire and inert gas. Not much thcker, but if your welder is rated for a 3/16" max penetration with steel wire and gas, you can load up some .035 flux core and get weld 1/4" pretty good. You will get sunburnt easier and the ole fingers will get alot hotter alot quicker using flux core

Also the flux core is mainly used by farmers or construction trades for feild repairs since all they need is a generator to supply power and not worry aabout dragging around a cylinder with gas. Works 10x's better on rusty steel than regular wire/gas does. Basically an arc welder/stick welder but in a MIG package.

 

How about a roll bar install with flux core wire?

Advisable or just rent a gas mig?

 

That's a no-no. It states very clearly in the NHRA rulebook (and probably the IHRA) All 4130 chromoly tube welding must be done by approved TIG heliarc process; mild steel tube welding must be approved MIG wire feed or TIG heliarc process. Welding must be free of slag and porosity.

Flux core welding is not MIG welding. Plus flux core welding produces slag.

 

What he said!

 

If the tube was chrome moly then yes a TIG application would be ideal, but if this is a standard run of the mill roll bar/cage (like 90% of kit bought roll bars/cages) it's mild steel not 4130, so MIG with either steel or flux core is fine. Might not win an engineering show but will work none the less!

 

Just for clarification Flux Core is not the same as MIG. MIG welding is actually GMAW. Short for GAS METAL ARC WELDING. Flux Core welding does not use a shielding gas and is not the same thing as MIG welding. Flux core produces slag and flux that must be removed. And as in a previous post, is not NHRA legal to use on a roll bar or cage.

 

I never have much liked the flux core or arc welding.. having to chip the lag off was never much fun.... I like my gas welder.. does everything you need it to do.. just takes some skill... and patients... espeially on the overhead stuff...