Why are you getting any waste at all? Don’t sift out any proportion of the grinds, just use it to calibrate grind setting. (mix all the grinds back up & brew)
If you do want to explore sifting for drip, dial in the grind (you might end up around 10-11% under 500 for a Chemex?) then just exclude the particles larger than 1600, or whatever gives you about 15% remaining on top of the largest sieve? Sifting out the largest component is also quicker than sifting out the smaller particles.
This shows some 500-1400Kruve sifts, expect a 1600Kruve in the top to allow about another 4-5% to pass through?
Kruve 500-1400