You Wrote:
Imirie Shims (invented by George Imirie) are wood frames with the outside
dimensions of a hive body, and about 3/4 inch tall.  A 3/8" by 2" notch is
cut into one of the narrow sides.
 
Imirie Shims are used to provide an additional hive entrance during the
honeyflow, and during requeening by the "nuc" method.   A more detailed
description of how the Imirie Shim is used is in this year's Brushy Mountain
catalog, and I believe somebody posted a copy of the description on BEE-L
last night.
 
My Reply:
Having a second enterance between the bottom and second supers seems like a good idea. However, by providing  an extra 3/4 inch of space between supers you will create a mess with comb built between the frames above and below. Why not just make your 3/8 X 2 notch in the bottom of the super its self. Then you could just plug it against robbing, or when it's not in use. The concept is good though as it provides extra ventilation, and allows field bees to bypass brood area.
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Best Wishes,
Stan Umlauft
Bay Point, CA USA
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