Hey @Gormly,
I had a quick look, as you said the file should run just fine but here are a few notes:
- for depth per pass, you can generally push it up to 50% of the endmill diameter on a Shapeoko. Which is consistent with @RTWD’s advice of 0.1" per pass when using a 1/4" endmill.
- 60ipm at 18.000RPM using a 3-flute endmill like the #201 grants a chipload of 0.001", which is just fine. Do not slow down the feedrate below that value, this would end up reducing the chipload down to “the danger zone” which is when the endmill starts rubbing rather than cutting, and that’s a recipe for tool breakage (and burning wood/a dull endmill too).
- I don’t cut a lot of plywood, but @LiamN shared good insights in this thread, that should give you ideas about the influence of the various types of endmills for the job.