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Assuming uncoated carbide, I would start with 450 SFM. So, now let's learn to do the math on that. SFM is Surface Feet per Minute. Your end mill is measured in inches. So, you have to do a conversion.
RPM = (SFM X 12") / (d X PI)
RPM = (450 X 12) / (0.375 X 3.1415)
RPM = 5400 / 1.1781
RPM = 4584
Now for feed rate. I would start with 0.004" per tooth. More math:
Feed = RPM X Feed per tooth X Number of teeth
Feed = 4584 X 0.004 X 2
Feed = 36.67 IPM
For depth of cut, I usually start with what I call 50/40. 50% of diameter for Axle and 40% of diameter Radial Depth of Cut (DOC). So, 0.1875" for the axle DOC and 0.150" for radial DOC.
Most of this information is in Machinery's Handbook. Examples of the math are in Machinery's Handbook.