half half half drawer method questions

[festal]

Hello all.  So I've been youtube learning and decided to try out the half half half method for drawers for my hand tool rolling cabinet.
Its not as easy as people on youtube make it out to be lol
Not having 1/2" and 1/4" baltic birch plywood doesn't help.

I think i got the fronts and sides figured out but what is the correct way to measure for the bottom panel?

 

[guybo]

take an actual measurement and subtact enough for slip fit,however I have used this to calculate material,just plug in the values then hit calculate it will give drawer bottom sizehttps://www.hingmy.com/cabinetcalc3.php

 

[festal]

take an actual measurement and subtact enough for slip fit,however I have used this to calculate material,just plug in the values then hit calculate it will give drawer bottom sizehttps://www.hingmy.com/cabinetcalc3.php

Thank you

 

[guybo]

you are welcome