Welding with flux core wire?

[David_viny]

I have read somewhere that using flux core wire on body panels can cause paint issues. Something to do with the flux leaching out of the weld and effecting the paint. Is this true? I'm thinking of doing some bodywork, mainly rust repair and I have a flux core mig that id like to use. Id rather not rent/buy a gas setup for the mig just to do a few repairs.

Thanks,
-Dave

[robertjra]

I would like to know this too I was going to start my smothing of the fire wall with flux core

[elitecustombody]

I would invest in a MIG welder,I know alot of us are on the budget, but for smaller projects,even Harbor Freight or Ebay MIG welder would be a much better tool,than flux core welder, $300-400 and you're good to go. If you want, I'll sell you my Lincoln ProMig 135 for $250 shipped,it's dusty,but works, I have used it for no more than few months, the wire feed sometimes chews the wire,so I just bought a Hobart. Now that I mention Hobart, you can pick one up at Northern Tool for $460,well that's what I paid,but worth a try.

[DarkoNova]

I know it's different everywhere, but the thing about MIG is where do you get the gas? And how much is it? Yeah you can get the welder and wire for like $400, but then how much extra is the gas/regulator/tank, etc. I think this is why everyone goes for flux core welders since the gas stuff just adds on a ton of cost.

I want to buy a welder to do some panel work, but can't make up my mind on just getting a Harbor Freight flux core unit or getting the cheapest Eastwood unit and then getting all the gas stuff.

[bdahlg68]

Flux core is lower up front, but not necessarily cheaper. The wire is quite a bit more expensive and if you burn through a panel, well... Look for an Airgas, they're everywhere and they should be able to fill cylinders and may also sell them. I have a flux core unit that cost about $150 from Northern Tool. It's a great welder for the money, but I'd still rather have a MIG I can run 0.25 wire in. Plus, it only has 2 heat settings, and that just isn't enough for welding sheet metal. If you can afford to pick up a gas MIG, do it. If it's going to prevent you from being able to doing a project, you can probably get by with a flux core unit, but again, I don't think the final cost will be significantly different if you get a good deal on the MIG.

[ErikLS2]

I don't think you'll find too many people that bought a flux core machine for welding clean steel that didn't at some point wish they'd gone with a MIG to begin with. They're good for farm guys or building maintenance guys fixing gates and stuff, that's about it. Look on Craigslist for a used Lincoln, Miller or Hobart. The gas is a non-issue once you see how much use you get out of it and the much better looking weld it produces.

[robertjra]

I got a harbor freight welder for $59.00 used with a 2 yr warn.. it works ok but I will get a mig after all of you are saying how much better it works

[bdahlg68]

I'm actually quite happy with the Northern Tool flux core I have, so I'm thinking I'll eventually pick up their next step up MIG.

http://www.northerntool.com/shop/too...2691_200332691

and I like the cabinets they have too....

http://www.northerntool.com/shop/too...0615_200460615

and they sell cylinders...

http://www.northerntool.com/shop/too...7977_200317977

[absintheisfun]

I started off with a flux core/mig made by Clarke, and it treated me well for a good 3 years. I ended up getting a Miller mig and like many have said, I wish I would have done it sooner.

Flux has its place, but Mig is definately cleaner and easer.

As far as effect on paint, I've never heard anything about Flux being bad for paint applications. In the areas that I have used my flux, it has had no effect on my primer or filler.

[BuzzKillian]

As far as the gas goes... I got a 1200# bottle from Weiler Welding. It was $110.00 for 100 year lease and I just had it filled (read exchanged) for like $30.00.
I have a Hobart 175

[grenade inspector]

based on personal experience, flux cores are great farm welders but they aren't for works of art.

[elitecustombody]

I know it's different everywhere, but the thing about MIG is where do you get the gas? And how much is it? Yeah you can get the welder and wire for like $400, but then how much extra is the gas/regulator/tank, etc. I think this is why everyone goes for flux core welders since the gas stuff just adds on a ton of cost.

I want to buy a welder to do some panel work, but can't make up my mind on just getting a Harbor Freight flux core unit or getting the cheapest Eastwood unit and then getting all the gas stuff.

The regulator,gauges and hose are included with the welder.You can buy the cylinder for couple hundred or rent it from local welding supply store.If you're in Cali, it can't be all that difficult to find a store near you, because most of them supply hospitals,clinics and countless local shops that need gas everyday.I own a few tanks that are about 4.5 feet tall and it costs around $25 to fill one up at local Airgas.

[DarkoNova]

The regulator,gauges and hose are included with the welder.You can buy the cylinder for couple hundred or rent it from local welding supply store.If you're in Cali, it can't be all that difficult to find a store near you, because most of them supply hospitals,clinics and countless local shops that need gas everyday.I own a few tanks that are about 4.5 feet tall and it costs around $25 to fill one up at local Airgas.

Ah, see I didn't know the regulator, gauges and hose came with the welder. I just looked at the Airgas site and found out they have a store literally 10 miles from me. Gonna have to check them out next week!

[nekkidhillbilly]

northern tools are century built and century and lincoln are the same company

[elitecustombody]

And Hobart is made by Miller.

[John Wright]

the flux leaching out of the weld and effecting the paint.

I'd be curious to hear an explanation for this...

The flux inside the cored electrode("gasless" FCAW) produces a shielding gas and also a slag system to further shield the molten puddle until it cools below a critical temperature. The slag also acts like a dam and helps hold the fluid molten puddle in place.
If you chip/brush/clean the slag off...how can it leach out? I think somebody is feeding you a line hoping you will take the bait.
70ksi steel is 70ksi steel whether it comes from FCAW(cored wire) or GMAW(solid wire) is irrelevant. Even if welded with GMAW, that can leave silicon islands on the cap of the weld bead and that must be removed before paint will adhere. GMAW is easier to use on sheet metal because it doesn't dig as deep as FCAW and allows you to weld on the thinner materials without burning through.

[elitecustombody]

^ I agree, if the weld has been cleaned up,it shouldn't affect the paint in any way.It's just that flux core is not ideal to use on car's sheetmetal.

[Happyfunballs]

FYI, I filled up my little bottle the other day (4ft tall) and it was nearly $60. Make certain you understand the bottle rental/purchase/lease agreement.

[elitecustombody]

Yeah, Praxair was raping me at almost $70 to fill up for years,until I sat down and called around and found best deal at Airgas for less than half

[Happyfunballs]

Airgas was $10 cheaper for the refill but wanted an yearly fee that was 5X the rate I currently have for 5 years. I've been with CeeKay for so long I was "grandfathered" into their good rates. Whatever.