Amada Fom2 4kw cutting 20mm

[Co2_Marcus]

Hello.

i have been cutting 20mm thick Laser quality S355 with oxygen and WACS 4mm nozzle and fairly pleased with the result.
edges are a tiny bit angled, kerf being wider at the bottom.

not sure how good quality cuts to expect and if this is as good as it gets with this machine
or what to adjust to get better results?
had some problems with too much water that lifted the laser head trace a bit too much, but right now it seems to stay between nozzle gap 1.4 to 1.6mm

here is some example of the results im getting.

any ideas on what to expect?
What to adjust or should i just be pleased with the results?

first when i started it wasnt cutting as good. changed cutting parameters and ended up with using 3600watt instead of standard conditions at 4000.
also had to lower duty to get good looking cuts.
right now im using 900mm/s, 3600watt, 500Hz, duty 80%, gas 0.07, focus 2.0

 

[Fermatseye]

Were you able to make progress? We have just commissioned a 2kW Amada and I am trying to learn the affects of the different parameters. Its sort of tough sledding with no guidance.
One problem I was having had to do with cutting larger circles (~2" dia), in which it would cut beautifully in quadrants 2 and 3 but would not cut through in 1 and 4.
Evidently this may be attributed to poor beam alignment, but multiple tape tests show that the beam (to my inexperienced eyes) is centered.