3/4" Mild Steel Disintegrating

[Stout]

I'm trying to cut 3/4" mild steel into a signature styled piece of art but the part is so narrow that it just melts. I'm running about 90 amps at 20 ipm. The final part needs to be about 1/4" wide but the heat retention is just too much. Any suggestions? I did cut it originally in .250. The original was hand cut with a torch and is .750 thick.

Victor

[jimcolt]

You could do this with a high definition class oxygen plasma on 3/4" at 200 to 260 amps.....the cut speed would be much higher with less heat input. This type of part with web sections that are thinner than the thickness of the material is not a good process for an air plasma system at power levels under 120 amps. A good candidate for water jet cutting!

Jim Colt Hypertherm

[WSS]

A water table would help big time. You can use a pump up sprayer to cool the hot sections before the arc has a chance to get to the melt temp.

WSS

[mkreed75]

Have you tried leaving it on the table and just cutting a few paths at a time? Maybe give it 10 mins between cuts this has helped us on some things.