Do you guys use gas or gasless when welding aluminized steel? The people I've talked to told me it's ok to use argon/co2 but it seems to me my welds are a little dirty. Wondered if flux-core is better for this. Thanks

 

Aluminized steel? I would think you exhaust is a 400 grade stainless..rather high carbon content...I would just run hard wire not flux core with 75/25

By dirty what do you mean? porosity (holes)?

 

No holes, just black burn marks around and discoloration. And that gray stuff that looks like cobwebs, which I assume is the aluminizing burning off. No, it's all mild steel with a coating of some sort, like galvanized.

 

If your welding galvanized then the welds will look dirty...Make sure you have good ventilation...The gas that emmits from galvanized products is toxic.

 

I know Ill get **** this and sayin I dont know how to weld, but I would rather weld exhaust and small metal with a flux core welder over a gas welder any day. So much easier and less to worry about. Yes they can look nasty if you dont have it set right and going to fast. If you have the heat and speed set good, go slow and make steady small circles it can almost look like a tig weld once cleaned up.

 

No...I wouldn't say that at all..everyone has their preference..Hard waire is the popular choice because it uses less heat and is more controlable out of position than flux core.

 

the flux core welder ive always used is a small 110 with .030 wire at were I used to work, exhausts was one of our things we did. Dont get me wrong I do love my 220 for other things..

 

Well my whole point is that they say to use flux for "dirty" metal like if there's any rust or whatnot, so it may be appropriate anyways. But nearly everyone so far says they use gas. My welds look fine, I just wondered if I could get better results w/flux on coated steel

 

Take a steel brush to it first and see if that helps...Butif your welding galvanized stuff there isn't a whole lot you can do

 

Use a gas mig on a low low heat setting, also the right wire speed, but base it on the thickness of the material your doing. If it is galvi, simply grind away the galvinized and it will weld fine.. Even when you stick weld or use a flux core wire, the cleaner( ground, cleaned up) the metal the nice and easier the weld will be.. Mig it and be done... The flux is basically the cleaner for what your welding as is the gas in a mig..