homemade National type hive extra frames

[GorgieBees]

Hi folks! As a newbie I'm looking for advice on a hive I got built as a joint project with a school. They made a national hive from scratch and in the Brood box I can fit 12 frames, so I have built a dummy frame there, but in the super it seems I can fit 15 frames (SN2 with no spacers). Should I build dummy frames and if so how many should I make? 4 seems a bit overkill, and that's 4 less frames for honey. Thanks in advance.

 

[itma]

You should indeed be able to just fit 12 Hoffman spaced frames (normally DN4/5) into a National brood - when everything is new!
Its different once you get some prop and you are trying to avoid rolling bees between frames. Hence the use of a dummy board!

The super should have exactly the same "rail length" as the brood box.
SN2's need some form of spacers - castellations and frame-lug push-on spacers being two commonly used.
Frame spacing in supers is ultimately down to beekeeper preference - within the bees' limits!
But brood frame spacing is about the space needed for brood cells and nurse bees attending to them - it has much tighter tolerances.


Dummy board (rather than frame). Should be thinner than a frame, and flat towards the frames, and hang vertically.
Think in terms of 9mm ply (14"x8" for a national brood) with a 'topbar' made from 10mm square stripwood. Close enough. But better if you were to edge it all round with strip, while still retaining the same 'face' dimensions as a standard frame.



Hive internal dimensions (and thus beespace) are the really critical factors.
Bees (and/or beekeepers) usually manage to work around other problems somehow!