A few observations on building supers:
 
1)  If you wish to be amazed, take a ruler out to your stacks of "standard"
supers.  I have found them to differ as much as + 1/4 inch ( a bit less than
a centimeter) from the the accepted standard height dimension.  I suppose
this has more to do with the shrinking and swelling of the wood than it does
with poor manufacturing quality control.
 
2)  To ensure accurate box building, two tools often overlooked are a
carpenter's square for the corners, and a flat surface to get the bottoms
flat.   You won't get good boxes by just banging them together by eye.
 
3)  Bee space between boxes is a function of the boxes and the frames in the
boxes.  This discussion thread concerns boxes; has anybody looked at frame
variations?
 
W. G. Miller
Gaithersburg, MD