Fine cut causing melting near pierce point

[singleslammer]

I just got my fine cut consumables. Ran a 14 gauge sign with pretty good result. Some of the smaller hole (interior of letters) had some globbing dross that indicates too slow a cut speed, I ran 100 ipm I think. Then I ran an 18 gauge sign and am having tons of glob buildup on small holes and am now experiencing a strange melting where the pierce point arc curves into the actual cut. I tried speeds from 80 ipm all the way to 250 ipm. The higher speeds improved the globby buildup but my gantry was getting really inaccurate at those speeds. I tried 5 signs with all sorts of different settings. The initial settings were set per the Hypertherm book of 78 volts and 45 amps. Seems pretty hot but am not sure how to adjust for lower amps. Suggestions?

[tcaudle]

Depending on your table you may not have the performance to cut small objects / holes at anything close to those speeds. Like running a NASCAR car on a gocart track. The thinner material needs higher feedrate. First thing is to do smaller holes at LOWER feedrates and turn off your THC and consider changing the arc gap (cut height) or lowering the cut current for those cuts.