Trying to cut down on project time, need help!

CNC Machines Shapeoko
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Hey there, I am working on a project for my church and need some ideas. I am making communion trays that look like cutting boards with 40 holes drilled in it. I am trying to cut down on job time, but not quite sure how. I am new to CNCs so I am not really confident with my xxl yet. I am cutting out 40 holes in 3/4" walnut. The holes have a 1 inch diameter. I tried doing just an inside offset with a tab, but the waste just went flying anyway. Carving out pockets for all 40 holes with a .201 is almost an hour cut time. are there larger end mills or drilling mills that could be used to accomplish this?

Any ideas?

BTW I have the carbide router.

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Seems like you might have some very conservative speeds and feeds. What is your depth of cut and feedrate?

Walnut is relatively soft so you can get a little more aggressive.

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You could: increase depth per pass from the default 0.04" to 0.08" (still ok with a #201 in walnut), and feedrate from 60ipm to 80ipm (with #201, at 18000RPM that’s a chipload of 0.0015", still OK)
and use tabs (say 2 per hole) to hold the inner parts, that would cut the 40 holes in 18 minutes:

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BUT then…cleaning up the tabs in 40 holes would probably take you almost as long as cutting the holes as pockets…

EDIT: the fundamental issue is that CC is not great at cutting small pockets, because of its retract policy. It will spend half the time retracting the cutter in the air…

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spindle speed - 19700
feed rate 65
plunge 32
depth per pass .1

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Which z-axis do you have? Might be possible to speed things up. And the thought of cleaning up 40-80 tabs over extended time to pocket… afters years and years of hand sanding, I will happily wait on the machine.

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I have the belt drive Z axis, I’m not too keen on 80 tabs either lol.

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Well actually I hate tabs too for that very reason, and last time I used them is about two years ago, this was just to address your point of waste flying away (I assumed your were using clamps). If it were me, I would use tape & glue workholding (as I always do), do inside contour cuts and no tabs, and that would probably work just fine. What I would do is choose the depth per pass such that the final pass is only cutting a very thin layer of material (removing the onion skin), hence very little forces, hence the tape would keep the waste in place easily, 1" is large enough of a diameter.
I would target a last pass of 0.02", so depth per pass of 0.73 / 7 = 0.104".

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