Feed/Speed Calculation with Custom Power Curve
I've created a custom power curve for my machine in HSMAdvisor. I realize this power curve may not be correct or realistic for my mill (a Tormach 770MX), but when generating a cut formula I noticed something curious.
If I let HSMAdvisor select the RPM and Feed Rate, it returns 10000 RPM (machine max) and 66 IPM (see screenshot) for a 1.48ci/min MRR. However, if I manually set the RPM on the same cut to 7500 RPM, the software calculates 97 IPM for a 2.18ci/min MRR -- presumably it's able to do this because there is more spindle power available (in my imaginary custom curve) at 7500 RPM than 10000 RPM: 0.38 HP vs 0.55 HP.
Should HSMAdvisor select the RPM and Feed that produces the highest MRR along the power curve, or am I missing some other factor?