>1:For engineering reasons (that I won't go into here) I would like to run the entrance as 3/4" ID tube approximately 16" with 1- 90 degree turn. I could run 1", but it weakens some details. Is this entrance reasonable? Do I really need to keep a min 1" ID? This will be a 3 deep frame hive.
3/4" will work.
>2: The walls this hive will most likely live on all face north and receive virtually no direct sun, so the entrance won't get any.....does it matter?
The entrance? Not really. The hive? Yes, you don't want a solar wax melter in your living room with live bees in it...
> How Much? Certainly with the normal hives, activity seems correlated to when they get good sun on the entrance....even more than outside temps.
An observation hive won't produce honey, so does it matter it they get to work earlier in the day?
>3: How much of an issue do folks find trash at the bottom of hive? Do people provide greater space down there for the debris and dead? Is some sort of screened bottom/tray worth while?
I guess if you want to get fancy, you could put one in. I've never had an observation hive that had anything of the sort. The Draper one I have has a lazy susan and a large space in the bottom and I do find myself shaking that out now and again... most hives (observation or otherwise) will need the debris removed in the spring after the winter die off. I just take it outside. I have also been know to clean it on a cold winter day by just unhooking the tube (which is usually full of debris) and dumping that on a paper plate and then scraping out what I can reach from the hole. Then take it outside before some of the half dead bees decide to wake up...
>4: the way I am designing this hive it is functionally similar to the Bonterra swingview (but mechanically quite different). It is hinged from the wall, and the hinge pin will serve as entrance. I can run the entrance as either top or bottom. All the observation hives I have seen have bottom entrances. Arguments for one over the other?
The top will have less debris clogging it, as you pointed out. The bees find them either way.
> I can see top entrance helping with keeping the dead from clogging it up...but might it provide too much ventilation in this case?
Ventilation should be adjusted by changing the vents to the inside. I see no issue with a 1" top entrance.
>5: does light penetration via vents need to be addressed?