I used to make a lot of stuff out of plywood - laser cut or CNC routered.  I always thought it was a shame that these designs are never quite universal.  That is, if you want a tight fit, each slot needs to be the exact width of the actual plywood it's slotting into.  The process was always:

Of course, if you don't mind sanding down the slot afterward, you can leave the dimensions slightly undersized, but I always thought that defeated the point of having CNC precision.

Design

Designing a flatpack brutalist bed

deSign_r

I used to make a lot of stuff out of plywood - laser cut or CNC routered.  I always thought it was a shame that these designs are never quite universal.  That is, if you want a tight fit, each slot needs to be the exact width of the actual plywood it's slotting into.  The process was always:
- design
- collect materials
- update design with actual measurements (seldom are the labelled thicknesses of plywood or acrylic accurate)
- layout tool paths
- cut

Of course, if you don't mind sanding down the slot afterward, you can leave the dimensions slightly undersized, but I always thought that defeated the point of having CNC precision.