Allen Dick writes
>
> I've concluded that the most practical escape boards for my purposes are
> the Quebec board, or a variation of that design.  However, I seem
> to recall discussion of the need -- to get the best performance -- of
> making a rim on
> either the top or the bottom of the board that is larger than the
> 3/8" rims that are typically sold.

I use these boards.  The rims on mine are probably about 1/2" and they clear
practically all of the bees out of the supers in a day.

I have not checked to see how effective they are over shorter periods of
time.

Frank.
-----
The very act of seeking sets something in motion to meet us;
something in the universe, or in the unconscious responds as if
to an invitation.  - Jean Shinoda Bolen

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