Hypertherm 600 dross problem.

[pottsie454]

I bought an older 600 from a guy on ebay. When I recieved it, it was obviously used quite a bit. The torch has taken a beating. First thing I noticed was I was getting some air from atop the white cup while in use... Is this normal? Its not alot of air, but I just know if it is normal or not.

I change all the copper consumables and with lots of different setting I am still getting quite drossy cuts. Here are a couple pics..

1/4 plate, new copper, 72 psi of clean air while cutting, amps max, using a straight edge with a consistent cutting speed

Any ideas?