A top bar hive from an old fridge
(originaly published in THE BEEKEEPERS QUARTERLY)
The top bar hive (tbh) is a long hive which uses no frames, just top bars 3.5cmwide. It has a lot of advantages - it is extremely cheap, it is simple to make and it is very flexible. All these factors make it an ideal hive for a beginner, but someone who enjoys experimenting with hive construction will also find it of great interest. For instance, it is possible to change the thickness of the top bars to investigate the influence of this width on comb development, and the hive walls can be made of different materials to test their usefulness. It was my initial idea to make the hive body from adobe, a clay/straw mixture. I have spent some time researching this age-old building material and I am convinced that it must be ideal for hive construction particularly due to its ability to maintain a constant hive temperature and humidity. Unfortunately, it is too time consuming for me to make such a hive from this material, so I needed to think of another way. It came by chance. At first I didn't recognise the opportunity, but there it was on my way to work one morning - an old fridge that someone had dumped in a ditch near my home. Initially I was very angry that someone could show such disregard for the countryside, fly tipping is all too common and once someone starts it soon escalates. Still cross, I made my way to the bus, then on the tube as I was nearing work (why do thoughts unconnected with work come to mind the nearer one comes to the work place?) I suddenly realised that I had there in that ditch the ideal body for the tbh! I now became extremely anxious about the fridge - what if some public-spirited person decided to clear it away? Was it worth cancelling lectures and going home early so that I could ensure possession of it and put my mind at rest? I don't know how I got through the day and as I made my way home a feeling of excitement alternated with that of impending loss. What joy though, when I saw it lying there untouched, I saw it though not as a fridge, but as the finished hive - with the door as its roof - full of deep combs, overflowing with bees. I was so excited I wheeled it home on a barrow and within two hours my tbh was complete! So, how does an old fridge find a new life as a tbh?
First I looked at the cooling system. Unfortunately it had been damaged so there was no chance to get the CFC re-cycled. I removed this and all the electrical connections and sawed the door away from its hinges. Lying on the floor, open to the top, I used what was the bottom motor housing as a porch and through this made a hole into the cabinet. I cut pieces of 3.5cm thick wood to the same length as the top breadth of the cabinet for the top bars and made a wooden frame around the fridge door so that this would just overlap the sides of the hive. The roof was then hastily covered with some old scrap linoleum. Two hours work and it didn't cost me a single penny!
A few days later a strong colony was going to swarm, so, using the Taranov board I made an artificial swarm and hived it in the fridge. To ensure that the colony built combs both straight and parallel (and with no brace comb) I used, initially, ordinarycombs in frames to separate the top bars. I then gradually moved these frames to the back of the hive and replaced them with top bars which had been fitted with starter strips of foundation. At the end of this season I extracted 20 kg (!) of honey from the combs in frames and there is still enough honey left in the 13 top bar combs at the front of the hive for winter food. Next year I will use no framed combs in this hive and all the honey produced will be cut-comb as ordinary extraction methods are impossible with these combs - their catenary shape, their large size and their fragility will not allow them to go through the extractor.
Using the tbh gives me a great deal of pleasure. What I like most of all about it is that the bees use the whole of the inner cross-section of the fridge (45cm wide x 42cm deep) to build their combs! It is a great experience to hold in one's hands such enormous, fragile, gently-waving, bright-yellow, freshly-built combs full of honey and brood! I know that normally are used much smaller combs (30cm x 20cm) which are much easier to manipulate, but in comparison to my combs beekeepers using smaller frames are missing out on a marvellous experience. In my opinion, deeper combs are much better for wintering under our Czech climate. On the other hand though, it is certainly better to use the sloping sides for the side walls (14 degree or bigger incline from the vertical). I did not follow this usual guideline and I am paying for it. Each time I want to inspect the combs I have to cut them away from the hive walls with an extracting knife! This difficulty can be overcome though if I add two internal walls made from plywood - I must do this next season.
The colony should survive the winter well in the tbh as the fridge is well insulated (4cm thick styropor), it has enough ventilation (the rear dummy is made from straw) and the plastic inner walls do not soak up any moisture. The fat that the combs are currently joined to the side walls should give an additional advantage - the bee space between the combs is closed making it easier for the colony to keep warm and will aid rapid spring build up. This sudden increase in bees next season and with them having no possibility of constructing more comb, may well lead to swarming, so another task for next year is to re-queen the colony with a non-swarming strain. And, if the next season is a good one, I'll be making my way to the CFC re-cycling point to get some more empty fridge's!