Skandia AR 500

admin

I am putting together some targets & stands and a friend has supplied some plates of AR 500.  I will be welding some mild steel square tubing on to the plates as brackets to set these targets on.  This plate is some pretty hard stuff.  I am using .035 FCAW with a Lincoln 180 wire feed machine.  Do I need to pre / post heat the plate material??  Any advise is appreciatedThanks
Reply:Ar 500 welds with standard low hydrogen process. Preheat is only needed on thicker plates. North American steel recommends 7018 I've good success welding ar 400 with 7018 as well er70s6 wire. I'm really not up to speed on flux core wires but I think that a wire that qualifies as a low hydrogen process and was rated for the thickness of plates that you are using would be fine.Tough as nails and damn near as smart
Reply:I tried a couple of small beads on that stuff and it was a different puddle.  But, I have to admit it was after a couple of beers in the garage.  The plate is 3/8" which will be thicker than the tubing, so I will give it a try and maybe turn up the amps from what I usually run this wire at.
Reply:Used  E-70T-1 with both CO2 and 75Ar&CO2 for welding AR500 plates for military document and weapons' safes. All welds were fillets in the horizontal position.
Reply:Weldinglifer I guess that you area career military guy.  Thanks for your service to our country.  I spent some time in the AF in the late 70's.  Is this E-70T-1 wire flux core or a MIG wire.  I can hook up the gas for MIG if needed.  I have a 10# of Flux wire on the now but change can be done.  maybe I should try to convince my wife I need anothe buzz box (like I just sold to get the wire feed machine)Thanks
Reply:E-70T-1 is a FCAW wire, E71T-1 or ER70S-3 or -6 all will work quite fine. The E-70T-1 will give the best appearance if you can position the work in the Flat or horizontal position.
Reply:So you are saying use a flux core wire with a shielding gas as well?  This can easily be done in a flat position
Reply:ak,E70T-1 wire is a certain "type" of wire, which has a Tubular (hence the "T" ) construction, aka it is a wire filled with some flux aka FCAW.But the detail is that there are MANY different types of FCAW wires.  The wire weldinglifer is refering to is most likely more properly called out as AWS A5.20 mild-steel  flux-cored E70T-1C/M where the E = electrode7 = tensile strength in 10's ksi0 = flat/horizontal welding position (a "1" would mean all-position)T = tubular aka fluxcore wire1 = more performance characteristic ratingsC/M = shielding gas type (C=CO2 and M=mixed gas)There can be other designations in the wires 'specs' as well.And yes, some FCAW wires use not only the fluxcore for the shielding but use a shielding gas at the same time.  FCAW-G (where the G indicates Gas) aka dual-shield as opposed to FCAW-S (where the S indicates Self-shielding aka no-gas used).But your Lincoln 180 machine most likely can NOT use most FCAW-G wires because it can't produce enough arc voltage at the welding amperage in order to run.  The 180-class machines can usually run (some) FCAW-S wires.  The wire you are using with the 180 machine is most likely an E71T-11 or E71T-GS wire like Lincoln's NR-211-MP wire.  Those types of wire are FCAW-S wires that can run with a relatively low voltage for the amperage being used.Also note that if you -are- using Lincoln's NR-211-MP wire, that there is a thickness limitation on the workpiece with that wire of 5/16 inch MAX thickness for wire diameters of 0.045 and smaller (which is all the wires sizes you could run with the Lincoln 180 machine anyway).  Your 3/8 inch thick plate is thicker than that, so if you -are- using the NR-211-MP wire then Want a recommendation on what wire to use?  With the machine class you have, just use regular solid wire and shielding gas.  The usual recommendation for welding AR plate is to use low-hydrogen procedures, and your best bet for that with a small machine and a home shop is CLEAN solid wire and gas shielding.  With stick, the recommendation would be to use a fresh sealed can of 7018 (or 7018 that has been dried and then stored in an electrode oven).  Mild preheat would be beneficial but not absolutely required for 3/8 inch AR500 plate.  Except that you do have to pay attention to minimum plate and air temperatures when welding AR plate (and other things too) and in Alaska that can make a difference as opposed to say Florida or southern California.    Standard low-hydrogen welding procedures should be followed.  Clean all grease, oil, paint, or other contaminants, clean all rust and corrosion off the welding area, clean the steel down to clean shiny bare metal, everything clean and dry, etc, etc, etc.  The best laid schemes ... Gang oft agley ...
Reply:MoonriseThanks for the greater details.  Clean, gas w/appropriate wire, store plates inside prior to work, clean, some preheat, grind, clean again & weld.  Possible multiple passes needed.  Possible a little post heat as well.  Happy shooting to follow