Stripes after finish pass on pocket bottom
I've been struggling to get a clean surface finish on the bottoms of pockets with my CNC router. There are usually faint rows from the parallel finishing pass that don't appear to be bumps or cusps. (photo attached)
After roughing, I'm using a 0.25" diameter, cove-nosed end mill (radius 1/16") to skim the final 0.03" off the bottom with a step-over varying from 0.125 to 0.06 (doesn't seem to make a difference). 80IPM, ~15000RPM
Lastly, I do the contour of the pocket with the same mill.
Pronounced "corn rows" that run in the same direction of the grain. Basically it looks like stripes of high-sheen area where a clean cut was made next to stripes that look dull and abraded, as if sanded. The final profile that finishes the walls and cuts to the same depth as the floor leaves a really nice, clean finish, so I know the mill is capable of doing it.
I've used a flat .25 end mill to finish the bottom of the pocket and this doesn't leave stripes that are as noticeable--it leaves a uniformly dull finish, like what you'd see from sanding with 200 grit paper. Contrasts with the clean profile left by the bullnose. Zeroing the two tools exactly the same is also a challenge, sometimes there will be 0.001 or less that's visible.
Tramming: I've trammed the machine using a 5" diameter tool to <0.001 about the y axis. I've had less success tramming about the x axis (the same axis as the wood grain) maybe 0.002 over that 5" span, but this error should go to nearly nothing when using a tool that's 1/20th the radius as the test tool.
Scraping/sanding/planing inside the pockets isn't an option--besides being time consuming, they're often too small to work inside. The products are home goods where surface finish matters a lot.
What bits do you use to cleanly finish a surface? Is it possible to get a surface as nice as a hand-plane?