Can argon/CO2 mixture be used for CO2 flux core

admin

I was reading some info on Ed Craigs website (weldreality.com) and he talked about using argon mixture instead of CO2 on flux core because it gave nicer results.If CO2 is the specified gas for a flux core mig wire then if I used a mixture of argon 85% / CO2 15%, would this work OK or would it stuff up the weld quality.That's the mixture I have at present for my solid wire welding, and here in Australia, a large mig bottle rental is $200 a year plus gas.Thanks,Keith.
Reply:it depends on what is specified by the manufacturer. mine can run bothDynasty 200DXPassport plus w/ spoolmate 100victor 315c oxy/(act and prop)Miller digital elitemilwaukee power tools
Reply:Originally Posted by turkit depends on what is specified by the manufacturer. mine can run both
Reply:Some FCAW-G wires are made to use CO2, some are made to use C25 (or similar mixed gas), and some can use either.btw, there is no such thing as a "flux core mig wire".MIG wire is wire used for MIG, aka GMAW.  It is a solid wire.If you have a tubular wire with a flux core, you have an FCAW wire.  That wire may be self-shielding (FCAW-S) or it may be a gas-shielded fluxcore wire (FCAW-G aka 'dual-shield').You can have a metal-cored wire, which is classed in it's own grouping (sort-of).  It uses shielding gas.examples:Hobart FabCo RXR is a gas-shielded fluxcore wire (AWS E70T-1C, E70T-9C) made for use with CO2 shielding gas only.  The "C" in the AWS-class call out means CO2 only.Hobart Fabcor 86R is a metal-cored gas-shielded wire (AWS E70C-6M) that uses argon-CO2 mixed gas blends.  The "M" in the AWS call-out means mixed-gas.Hobart Excel-Arc 71 is a gas-shielded fluxcore wire (AWS class E71T-1C, E71T-1M, E71T-9C, E71T-9M) that can use either pure CO2 or argon-CO2 blends.Read the specs on the wire and see what it is made to use for shielding gas.And no, don't go and run some gas if the wire is an FCAW-S wire.  You would just be mucking around with the arc and metallurgy.Hobart  The best laid schemes ... Gang oft agley ...
Reply:Thanks very much Hobart,I'll see what's available that can use my existing gas.Keith.
Reply:There are many flux-core wires for mixed gas, but few that are meant to be used with 85/15. Most that I have seen specify a minimum of 20% CO2. Still, unless you are building the proverbial bridge over the daycare center, the odd 5% probably won't make a huge difference. Ask your supplier what they have available that will work with your mixture.JohnA few weldersA lot of hammersA whole lot of C-clamps
Reply:Thanks John,I went Googling for flux core wires yesterday and that's exactly what I found. I wonder if I can buy a CO2 fire extinguisher so I only have to pay for gas. I forgot which forum it was where someone was using one of them.Keith.