Category Archives: Boards

Dummy boards

Can you have too many dummy boards? Well, obviously you can, but having made half a dozen last winter and another three last night I’ve yet to suffer from an excess of them. In fact, I’m going to have to make some more this weekend.

National hive dummy boards DIY

Dummy boards …

I’ve run out of dummy boards this year for three reasons. Firstly, I’m using the Demaree method for swarm control much more and so have two brood boxes to control free space in (and I usually remove frames of stores in the top box). Secondly, I’ve been using three frame nucs for queen mating, some of which are in five frame nuc boxes. Finally, with several swarms captured in bait hives, my colony count has increased.

Dummy boards are brood-frame-sized (length and height, but not thickness) pieces of something, with a simple top bar. The something is probably ideally a nice piece of red cedar about a centimetre thick. However, all mine are 9mm plywood from the offcuts bin in my local timber merchant, or stuff I’ve recovered by dumpster diving during refurbishments at work (I have no shame). I cut a piece 355 mm x 205 mm and simply glue and nail a top bar from 9mm stripwood along the longest, straightest edge.

Eleven frames plus dummy board

Eleven frames plus dummy board …

I’ve seen all sorts of designs on the web. Some made from a Correx-lined standard brood frame, some with side spacers and some with insulation. Although there is a case to fill a large amount of excess space with something like an insulated fat dummy (e.g. when housing a nuc-sized colony in a full brood box) most of the time a dummy board will simply be occupying a small strip of space that would otherwise be filled with brace comb. Typically this is when you have eleven brood frames in a National-sized box. When new, you can squeeze a dozen frames in. However, as soon as there’s some propolis it gets nearly impossible to add or remove the last frame without rolling bees. In this case it’s better to use eleven frames and a dummy board.

Spacers and any other embellishments seem totally superfluous to me. If there’s space for a full frame I’ll use a full frame, so why purchase a full frame dummy board lined with Correx? If I want the dummy board to be a certain distance from the adjacent frame I’ll put it there … and in a couple of hours the bees will have propolised it into place. Finally, if you use poly nucs, or have roofing felt on the roofs of adjacent hives in the apiary, a dummy board makes a great place to stand the smoker when not in use during inspections (from experience I can confirm that neither poly nor roofing felt appreciates exposure to a hot smoker 🙁 ).

Note: After writing this I checked the price of dummy boards with major beekeeping equipment suppliers (I’m thinking of writing about beekeeping economics in the winter) and was horrified to see that they varied between £5.75 and £6.12. Dummy boards are the perfect example of something that is well worth making … even more so because the most expensive one is plastic, so would melt under my smoker 😉


Poly nuc insulated eke

Insulated eke with block of fondant in place

Insulated eke

The lid on Paynes poly nuc boxes is very thin.  This, and the internal feeder, are the weakest features of what is otherwise a well designed, robust and useful box.  You can improve the box hugely by butchering it removing the internal feeder.  This generates an eight frame nuc box which is also a good size (and weight … when struggling up or down a ladder) for housing all but the largest swarms. However, other than during the summer, the lid is far too thin.  On a morning with a heavy frost the thawed patch above the cluster is very obvious.  I’m convinced that top insulation is very important; I build crown board with internal insulation or roofs with integral Kingspan insulation for all my full-size hives.  With a little ingenuity and some primitive woodworking skills it is possible to construct an insulated eke for these Paynes poly nucs that has the additional advantage of allowing you to feed fondant to the colony.

Construction details

Construction details

Kingspan and most other expanded polystyrene-type (that’s probably not exactly the correct term, but it’s a description most will understand) insulation is 50mm thick. Since my woodworking skills are limited and I lack anything other than a simple saw I have to work with the softwood  sizes available off the shelf (at my excellent local Shepherds DIY store). Therefore, using 46 x 21mm softwood I build an eke, with simple rebated joints, that fits onto the nuc box, outside the short raised lip. This then needs an additional shim of 9 x 21mm softwood around the top edge. I add a thin strip of 3mm thick stripwood to the inside top edge of the eke and then create the raised lip (over which the lid will fit) using 32 x  9mm softwood (this is much easier to show in a photo than to describe). The intention is that the lid fits neatly over the ‘new’ raised lip, forming a reasonable seal against the weather.

Jablite cut to fit

Jablite cut to fit

After adding two to three coats of a suitable bee-safe wood preservative like Ronseal Fence Life I prepare a block of Kingspan or Jablite insulation, carving out a rebate to fit the raised lip of the eke … again, the photo should make this much clearer. FInally, cut a hole in the insulation to take a “carry out” food container with fondant. Don’t discard the piece you cut out … use it to fill the space if you’re not going to be adding fondant.

Inner corner detail

Inner corner detail

In the summer I usually use 2mm Perspex crown boards on these poly nuc boxes. After an inspection they can easily be slid across the top of the box, pushing bees away and down out of the way. These crown boards have no feeding holes in them. Therefore, in the winter I prepare a sheet of thick translucent polythene with a suitably placed flap over the top bars, add the fondant block and the insulated eke, topping the entire thing off with the 2mm Perspex sheet and the poly lid. The latter can easily blow away – make sure you strap it down or add a brick on top.



Clearer boards

One visit or two? If you shake the bees off the frames (or use a leafblower) you can clear supers in a single visit. However, juggling all those frames on a hot day with the air full of bees can be a little trying. Although it takes two trips, I prefer the less disruptive approach of using a clearer board. The usual approach is to insert a Porter escape into the hole in the crown board and return the following day to find the super largely empty. But not always. Porter escapes have moving parts and a bit of propolis or a fat drone can easily block them. There are a number of alternatives, with Thorne’s selling about eight different types of escapes, as well as the conventional Porter unit. I’ve used several alternatives but have settled on the design shown in the picture (which I originally found on the Beekeeping forum described by ‘Poly Hive’ but they’ve lost all the images in a server crash) as it works extremely well. It has no moving parts, clears supers in as a little as a few hours – probably due to the space underneath and the widely separated exits – and, most importantly, is simple and inexpensive to construct.

Clearer boards

Clearer boards

Construct a flat, square and true eke from 46 mm x 21 mm softwood (see a previous article) and cover it on one side with a sheet of 4-6mm plywood. Glue and screw or nail the sheet of plywood in place. From now on I’ll refer to the ‘top’ as the plywood. Acquire a rhombus escape from Thorne’s (hint, these are always discounted in the sales, usually to £1). Cut the lozenge-shaped rhombus in half across the shorter diagonal using a small fine-toothed saw (see image). The resulting triangles should be offered up into opposite corners of the underside of the clearer board. Before fixing them in place drill a 2-4cm hole through the plywood – as close to the eke as possible and as far from the rhombus ‘exit’ hole. Refer to the picture which should be self-explanatory. Finally, fix the rhombus halves in place – I simply fixed them down with a thin smear of Gorilla glue. Slap a bit of wood preservative all over the exposed bits once the glue is dry.

Clearer board in use


Put the clearer board underneath the bottom super you want to remove, with the plywood sheet at the top. Return later in the day or after leaving in place overnight. You should find that the supers are more or less empty of bees and can easily be removed for extraction. The bees will be densely clustered on the underside of the clearer board. For some reason the bees usually seem very well tempered and can be given one good shake to return them to the brood box.

Perspex crownboards

Crownboards cover the hive under the roof and are typically ply with one or two holes designed for feeding and/or Porter bee escapes. Since the most basic function they serve is to prevent the roof being propolised down they can be as simple as a sheet of thick polythene cut to size. The semi-translucent stuff they wrap new furniture in is particularly good. Assuming bottom bee space this can be laid across the top of the frames, easily peeled up for inspections and discarded once it gets too messy. With good insulation above, condensation is not a problem.

Perspex insulated crownboard

Perspex insulated crownboard

However, I prefer crownboards that are rigid with inbuilt insulation, that lack holes and that allow me to see the colony with the minimal possible disturbance – for example during autumn feeding. For a few years I have used Perspex crownboards. These need insulating to avoid condensation so more recently I’ve been building reversible Perspex crownboards with inbuilt insulation.


Build a square (flat and true … by clamping it to a 46cm square template of thick plywood) eke out of 46 mm x 21 mm softwood, using simple screwed and glued joints. Cut 4mm thick Perspex or polycarbonate to 46 cm square.  Don’t be tempted to use 2mm Perspex, it tends to warp and this ruins the resulting bee space.  Use a strong sharp knife and a metal straightedge to carefully score the Perspex deeply and then (with a surprisingly hard) sharp blow, break it along the scored line. This is easier if you clamp the sheet to a table edge, using a piece of wood to hold the sheet down and prevent it from moving. Place the Perspex on top of the eke and then cut four strips of 6mm thick softwood ~45cm in length to create the bottom rim of the cover board, overlapping slightly at each corner. Note that 9 mm is too thick and usually results in some brace comb being built on the underside of the Perspex. With the rim in position use a 3mm bit to drill through the thin rim and just mark the Perspex – you probably need 2-3 holes per edge. Remove the softwood rim, but keep a record of the order they were in as you will need to put them back in exactly the same positions. Remove the Perspex and drill through it at each drill-marked point using a 5-6mm bit. This is critical. If you screw the rim in position through a hole in the Perspex that is too small you will inevitably crack the Perspex. Put the Perspex and the softwood rim back in their original positions and fix the latter in place with 4mm x 30mm screws. Now for the insulation. Kingspan and most other expanded foam-type insulation is available in 50mm thick sheets. Kingspan is particularly suitable as the foil cover makes it a bit more robust. It can be easily cut with a sharp knife. Cut the sheet to size to fit within the thick rim of the cover board. Use gaffer tape to seal the edges of the insulation and to create two simple ‘handles’. Finally, fix an additional rim of 9mm x 21 mm softwood around the thick (upper) rim so that it is deep enough to accommodate the Kingspan.

Fondant and Apiguard

Fondant and Apiguard

In normal use the Perspex sheet is placed immediately over the brood box and the insulation can be lifted out to view the colony. For Apiguard treatment in the autumn or feeding small blocks of fondant in the spring simply remove the insulation and reverse the crown board. Put the insulation on top and replace the roof. If you use fondant in the autumn the addition of a separate 46mm eke below the reversed crown board gives sufficient space to accommodate a single 12.5 kg block split into two halves directly on top of a queen excluder. The bees will usually eat enough within a couple of weeks to allow the removal of the eke. Once it’s all gone, remove the empty plastic bag and the QE and reverse the crownboard.

No condensation under a well-insulated Perspex crown board

Midwinter cluster

In mid-winter you will usually find the cluster immediately below the Perspex – the warmest spot in the hive. This image (left) shows an older style simple Perspex crown board (with a blocked feeder hole, something I now omit) from which the 50mm Kingspan insulated cover has just been removed. Despite the sub-zero temperatures there is no condensation.