excessive bevel when cutting circles

[Geo-Con]

we are cutting 115mm diameter circles in 3mm mild steel sheet on our TM2 machine, with 100V on the AVHC and 180"/min feed rate. on 2 sides of the circle the cut is very good and on the other 2 sides we have excessive bevel, both in the positive direction. ie. a trapezoid cross section.
what could cause this? i don't believe it is torch head misalignment, as both bevels point in different directions. the cut is clean with very little dross. even parameter adjustments that result in a poorer cut still have this bevel. any suggestions are appreciated.
cheers
sean

[DSL PWR]

Try slowing down. It could also be your tip, so change your tip

[Geo-Con]

can anyone recommend the parameters to cut with? the last post was cutting at 80Amps, now we have reduced it to 60 Amps and at 45 ipm. the bevel is a bit less, but still there. anyone who has cut similar please let us know what speed, volts and amps. we are using a thermal dynamics cutmaster 151.
cheers
sean

[DISCONNECTED]

Try turning off the torch height control and slow down.Click on this link. http://www.centricut.com/TA_CuttingSmallHoles.htm

[Geo-Con]

thanks guys. cutting nicely now.
halved the amps to 40A, turned the AVHC off, used a small 40 amp tip and dropped the speed to about 65 IPM.
thanks for the help