There have been numerous discussions, on various beekeeping websites and forums, about the weight of beehives. Many beekeepers wish to monitor the performance of their bees, or perhaps they wish to ensure that their bees have sufficient stores when winter is approaching.
During the periods when nectar and pollen are being collected by the bees, the increase in weight of the hive can give a good indication of the amount of honey being stored by the bees. If the hive can be weighed accurately then the actual weight of honey can be estimated easily by subtracting the weight of the hive components and the weight of the bees and brood.
During the winter months, when the bees are feeding from their stored honey, the hive weight reduces, and if the weight of the hive components is known accurately then it becomes easy to estimate how much stored honey is still available to them in their hive.
In the various discussions on this forum about this subject of “weighing hives”, various opinions have been expressed. Some people with years of experience just rely on hefting their hives, to determine whether their bees have sufficient stores. The comments about hefting seem to be very subjective, indicating “very heavy”, “heavy enough”, and “not heavy enough” (or some similar sort of explanation).
Some people have expressed a very real desire to be able to accurately know how much their hives weigh. This can present a dilemma to them, about what kind of weighing system to use. Some people may wish to use remote sensing equipment, which represents a level of cost for each hive they wish to monitor. Even if a beekeeper chooses a weighing method where the same piece of equipment is used to weigh each of their hives, many of the devices have been cumbersome to use. Some people have spoken of using a luggage scales, or spring balance, or similar device – but these all require the actual lifting of the hive. In this respect they are doing hefting with a weight measuring device. For people who have many hives, this requires a level of physical exertion which can tire them more than they would wish.
Having described a situation where hefting (of whatever kind) is exhausting, and in many instances gives only approximate results, I have “put on my thinking cap” and come up with an elegant solution. I have designed and built a hive lifting tool which incorporates digital-scales, which enables hives to be weighed in a matter of a few seconds per hive.
My hive lifter weighs just over 4kg, and can lift hives which have only 40mm clearance below the hive base. By this I mean if there is 40mm clearance between the ground, paver, or pallet on which the hive is placed, and the underside of the hive base, then my hive lifter platform can slide under the hive. If there is greater clearance, then the hive lifter can be used with a space as great as 400mm between the ground and the hive base. The hive lifter can be adjusted for any clearance between 40mm and 400mm in just 10 seconds or less, and a weight reading can be obtained in another 5 seconds.
If all of the hives in an apiary have similar construction (with similar ground clearance), then the height adjustment only needs to be made once, and accurate weights can be determined in just 5 seconds for each hive. No heavy lifting is required, as the operating lever has a 10:1 mechanical advantage, meaning that a weight of 50kg can be lifted with just a 5kg effort onto the operating lever. The hive needs to be lifted by only a very small distance – a centimeter has been sufficient – and does not cause any disturbance to the bees.
I have deliberately made my hive lifter to weigh just one end of the hive, to enable the device to be compact and light in weight, although it is robust in its construction. By weighing the rear part of the hive an accurate assessment can be made, rather than the approximation which can be made by manual hefting. If the actual weight of the hive needs to be determined, then it is necessary to repeat the measurement process at the front of the hive, and add the two values together (rear weight, plus front weight). It is because a weight reading can be obtained so easily and quickly that it is possible for the front of the hive to be weighed before the bees have much opportunity to react if they might wish to do so.
If anyone has an interest in knowing more details, please send me a private message.
