Weighing each side and adding the two weights gives a pretty accurate
answer provided the floor resting bars are close to the side of the
floor (I have seen hives with the resting bars some way in - in which
case the moments are against you)
It makes life easier if you make up a lifting hook to bring the spring
balance up to nearer face level. My one is made from a 8mm (5/16) steel
rod 700mm(28") long with a 50 x 10 (2"x3/8") square hook at the bottom
to hook under the edge resting bar of the hive floor , and a 20mm(3/4")
round loop at the top for the spring balance. This brings the spring
balance up to a more readable level when used on hives mounted on 300mm
(12") high hive stands.
Here in East-central Scotland our single brood box" Smith "type hives
need to weigh at least 35kg (77lbs)-weighed without roof - to get them
through the winter. Usually when returned from the heather they'll have
packed enough heather honey into the brood chamber to have reached this
weight. The girls who don't make it on their heather holiday usually
need feeding with sugar syrup-about 5 or 6 kg (11 to 13 lbs) made up at
1kg to 1 imperial pint of water(there's mixed units for ya). I remember
my father saying that the allowance during wartime rationing in UK was
about 12lbs sugar per hive.(remember our UK hives are smaller than most
places -50,000 cells for a UK Smith or National as opposed to about
61,500 for a standard Langstroth brood box).
 
Safe wintering
 
Alan Riach
Bathgate - Edinburgh,Scotland.