Would a little flux core unit be alright for small body work jobs? (welding in filler plate into rust holes etc..) only reason im asking this is i have an opportunity to pick one up for 2 bills, and gas can get pricey...only thing that paranoys me does the inert gas inside this "flux" actually produce mig style welds? i cant wrap my mind around it and im convinced i will encounter porosity

 

I've been able to get nice welds with a stainless flux-core wire. It wasn't porous at all and it's been holding together very well. The only problem is that they're "ugly" because of the crap that floats on the top of the puddle. Once they're scraped or brushed off, the welds are pretty nice, but no, they won't be exactly like a MIG weld.

 

flux core wire welds on there own are kinda gritty, but with 75/25 gas they make some of the prettiest mig welds possible.even mild steel wire comes out shiny and blue tinted, and stainless wire gomes out nice and golden.the only problem with flux core on body work is that, flux core wire tends to burn hot, and on light gauge stuff u might run into problems.

 

couldnt resist so i went out to the garage and laid a bead:


mild steel flux core, 72/25 gas 3 passes welded spray arc, notice the lack of spatter, another reason i like flux core wire. but like i said good for heavy stuff not for light gauge.i think for 200 dollar theres a lot off thing u can weld with it tho.

 

Go with a gas welder. It's the initial investment that kills you. Get the biggest tank you can, here in the states, I pay $21 to have a 20 ft/2 tank filled or $45 for a 390 ft/2 and believe me, the 390 lasts a long time on a MIG.

 

how much is a 20fttank cost initially?...i migth be able to buy a 390 from my shop teacher for cheap...

 

I would definitely get a regular mig welder before a flux only.

They work fine but if you plan to do use it a lot or keep it for a while then you will regret it.

 

Ok, there is a bit of misinformation floating around in this thread.

First, we need to distinguish between the different welding processes involved.

MIG, or metal inert gas, is an obsolete term for GMAW, or gas metal arc welding. It has been changed mainly because of the fact that many gases used by the current GMAW welding process are NOT inert gases. These include carbon dioxide, hydrogen, oxygen, etc. An INERT gas, is a noble gas located to the far right of the periodic table. Helium, argon, etc. GMAW also uses a wire feeder and gun.

FCAW, or flux cored arc welding, is NOT THE SAME AS GMAW. Typically flux cored power sources are used on thick weldments, or where shielding gas wouldn't be an option, such as outdoors. Weld beads from FCAW can be just as clean and pretty as those from a GMAW machine given proper setup and skill with the machine. FCAW wire does NOT contain a gas on the inside of the wire. Think solder flux and you will understand the concept.

Now that we have done that, we can look at why "flux cored 'mig' welder" is completely wrong. There is no such thing as a flux cored mig welder. However, there IS such as thing as dual-shield welding. It uses a GMAW power supply with FCAW wire and is typically used with very heavy weldments. FCAW welds are not typically "gritty" as Rob... points out, and if they are, it indicates improper setup, lack of skill, of poor machine quality.

 

like the flux on SMAW, thats how the gas is created without adding additional gas.

 

there's no way you can weld body panels without gas. I've tried and it burns right through

 

^ ^ you just suck!

ive welded body panels with 1/8" stick welder , my flux core, regular mig, tig, you name it. i wouldnt say that it was right or couldnt have been done better but i can get it put together. as far as a flux core blowing holes in thin metal, its all just a matter of getting you and your machine set up right.

 

Flux is there to be used without the gas if u arent able to get the gas where your welding, in the case where you have acess to gas you can use it with the flux wire, it will have a layer of slag over the weld to protect from the air as it cools, but if you dont want flux than change out the wire and get gas, and yes you can weld body panels with flux and no gas.

 

I found that flux core wire doesn't come in as small diameter as mig wire, so I would get a bit more burn through but it is possible if you're careful. You could get a mig setup that accepts flux wire too.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by reactone &raquo;</TD></TR><TR><TD CLASS="quote">I found that flux core wire doesn't come in as small diameter as mig wire, so I would get a bit more burn through but it is possible if you're careful. You could get a mig setup that accepts flux wire too.</TD></TR></TABLE>

That's because GMAW wire is solid. FCAW wire is hollow.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PolishSasquatch &raquo;</TD></TR><TR><TD CLASS="quote">how much is a 20fttank cost initially?...i migth be able to buy a 390 from my shop teacher for cheap...</TD></TR></TABLE>

If you can get a used tank, you can save a lot of money. Depending on where you live and where you buy the tank, prices will vary. But locally for me, a 20 ft tank is $100 brand new filled. A 390 ft tank is $175 brand new filled, you own the tank. Your paying for the welding and inspection, and valve. The extra material isn't that much so a larger tank isn't that more expensive. But like I said, for a stationary welding outfit, or if you can deal with a 390 ft tank on the end of your cart, the 390 tank only costs $45 to fill, vs $21 to fill a 20 ft tank. Makes no sense unless you need that tiny tank for one of a few reasons...