How much better is solid core MIG wire with gas
then flux core with no gas (on them little Lincolns)
I've ran the neighbors Lincoln SP-135 Plus with
flux core and no gas, but wondering how much
better it would be with the gas (and solid core)
Specifically, what can one expect to be better
as far as characteristics, and what those characteristics
might be. i.e. speed, smoothness, wire speed?
(can you move slower, less wire etc?)
In my experience, it's like night and day. Using C-25 to shield
ER70S6 wire, you can get beautiful welds with minimal spatter. That
is, the welds are paintable with no further grinding, in most cases.
Wire feed speed seems about equivalent between processes. I only use
flux core when either I don't have access to a gas cylinder, or I'm
out in the wind (like on my back, under a truck). Personally, I hate
flux core. Maybe other weldors have more luck with it.
3 things needs to be mentioned,
1; flux core will give much deeeper penetration than solid with gas
2; with flux travel direction should be "backhand"
3; flux can be used with dirty or rusty metal it will self clean the
metal as you move along.
solid wire (MIG) preffers clean metal.
When you switch from fluxcore to solid wire and gas you will have to change
the polarity so you're dcep (electrode pos) With the lincoln it's just a
matter of changing two wires around. I always thought flux core (dcen)
penetrated better than dcep-mig. But the weld beads look alot neater with
the c25 mig configuration. There is less spatter, and no slag to scrape off.
There is a noticable difference between the two. If you're going to just
weld busted stuff and you're not concerned with the neatness, use the flux
core. You wont have to buy or rent gas, and you can take it anywhere with
ease. If you do change to gas, you wont want to go back. As far as voltage
or wire speed (amperage is adjustable as well), the machine should come with
a chart. I have a miller and it's located right on the inside cover.
The only thing you lose with MIG as opposed to self-shielded Flux-core,
is the ability to weld outside.
MIG is an indoor welding process.
Even a slight breeze will rip away upour gas shield and give you
Other than that the welds are cleaner, faster, and more versatile as to
The advantage would be for your gas supplier only.
Flux core is also known as inner shield and hard wire / gas as
There is such a thing as dual shield where the wire has an inner core
of flux-like additives, but also requires an outer gas shield. This
uses a specific dual shield wire (such as ESAB 7100 ultra) that is
different from standard flux core inner shield wire.
The inner shield for flux core needs to have components which form a
gas shield, as well as components to deoxidize/clean the metal being
welded. My understanding is that with dual shield, the gas shield
obviously provides gas shielding and the components in the wire core
are more for cleaning / deoxidizing / floating out crap, etc.
I have welded a bit with dual shield in Ernie's class and it is a
magnificent processs. You get high penetration like with innershield
and very little spatter like with outershield. The flux/slag comes off
very easily to reveal beautiful welds.
If any one in Seattle wants to trade for a 10 lb. spool of 0.045 dual
shield wire--email me. My 170 amp MIG box doesn't have quite the
necessary grunt to run this stuff.
dantzler (AT) d r i z z l e dot c o m
Normal Flux-core wires are more properly called
Adding gas to a flux-core wire gives you "Dual-Shield", or more
correctly "Gas-Shielded Flux-Core".
The wires are both Flux-core, so they are a metal tube filled with
flux, but they are very different wires, and can't be interchanged.
Self-Shielded runs in DC Electrode Negative, while Gas-Shielded runs in
DC Electrode Positive.
Dual-Shield takes quite a bit of power out of a machine, and is best
run in larger MIG machines, but a small 220volt MIG could run 0.035"
Dual-shield, just not all day long.