The bit I was using was:
https://www.inventables.com/technologies/solid-carbide-2-flute-straight-end-mill-10-pack
It appears to me (given my as yet limited understanding) that this bit is similar to the Onsrud 56-240 which has a chip load of 0.003-0.005 (according to Onsrud’s chart for hard plywood).
So given that Feedrate = RPM x chip load x flutes
then using the Dremel’s lowest possible RPM (5000) we have
Feedrate = 5000 x .003 x 2 = 30
But the RPM I was using was probably more like 10,000 so that would give us
Feedrate = 10,000 x 0.003 x 2 = 60
So it would seem that the Shapeoko should have had no problem cutting through birch plywood at 30ipm yet it bogged down, stopped, and drilled into the wasteboard at 10ipm.
So if this isn’t due to limited torque of the Dremel, I am clueless as to what might be causing the problem.
I am also clueless as to what sort of cutting depth would have been best for this. It isn’t clear to me how the Onsrud chart information should be used to determine depth of cut.
Please help!