I hear flux core tends to be a little hotter because of the larger wire size involved (larger so it can contain the flux) so with metal already thin by rust, this may be a problem. I have never personaly tried flux core though. I run .025 steel wire with a mixture of 75% argon and 25% CO2. This setup works well for me, but requires having the tank for the shielding gas.

http://www.farmindustrynews.com/ar/farming_continuousfeed_mig_welding/index.htm


BiggerHammer
"The key is in knowing where to hit it"