Eugene E. Killion in "Honey in the Comb", describes a false bottom or
slatted rack as follows:
"The false bottom is made with two railings that are 18"(457mm) long,
15/16"(24mm) in width, and 9/16"(14mm)thick. The slats nailed across the
top are 13-7/8"(352mm)long,3/4"(19mm)wide, and 5/16"(8mm) thick, one
crosspiece 4"(102mm)in width is nailed in front with the slats spaced
5/16"(8mm) apart. The wide board placed in front discourages the bees'
tendency to chew out the front bottom corners of the frames that are so
close to the opening.
To create a bee space all around, four small staples are driven into the
bottom of the two railings, extending out 5/16"(8mm), two more are driven
into the back end of the false bottom and a nail or staple is placed on
each side of the 4"(102mm) front crosspiece and back crosspiece. The bees
will not propolize the false bottom when these nails or staples are used,
but they would if the railings or slats were touching the bottom board.
The top of the false bottom must be 5/16"(8mm) shallower than the top edge
of the bottom board."
Killion describes the bottom board required for the false bottom as
follows:
"The bottom board we use was also copied from Dr. C.C. Miller's, which he
described as' a plain box, two inches deep, open at one end.'"
Killion's book also has good diagrams of all this equipment.
Honey in the Comb
Eugene E. Killion
1981
Dadant & Sons, Inc
ISBN Number 0-915698-08-0