Bailey Comb Exchange
A Bailey Comb exchange is an excellent technique that can be used for a couple of reasons:-
1) Replacement of old brood frames with new. If you haven't gotten around to replacing your comb for some time and the comb in the frames are black and/or full of grotty drone brood a one-time change may be the answer instead of wasting brood with a shook swarm or changing just a few frames at a time.
2) Moving bees onto different sized frames. You might have purchased a colony on standard sized frames and want to move to say, 14 x 12's or Commercials.
A good time to do this is in spring before you need to put a super on the hive, or in late summer after the supers have come off.
The procedure is quite simple. You'll need a brood box with the new frames in, as well as a queen excluder. An eke is also beneficial to make a top entrance. And if you use an eke, you'll need an entrance block or some means of closing the bottom entrance when the top one is being used. An eke is a rectangular frame of wood - say 25 or 50 mm high - that can form a spacer between the two boxes. In it a hole is made in one side to allow the bees to fly.
This is what you do. (Note there are shorter methods than this but there's no rush, - let's work with the bees!).
Place the new brood box with frames on top of the brood box you want to replace. (No excluder for now). Place a feeder on top of this surrounded by an empty super and leave them for a week - continue feeding with 1:1 syrup if the feeder becomes empty. If the weather is cool - say in spring time - then put some old cloth or insulation around the feeder. Hopefully the bees will realise there's food above and use it and start to draw comb. Once there is some comb drawn you can remove the top box and find the queen in the lower one. What we want to do is to put her in the top box but with the queen excluder between the two boxes. If you are simply replacing old comb with new you can put her on the frame she is on in the top box, closing up the space below by pushing the frames together. If you are moving onto a different sized frame you may need to cage her until the hive is back together and then allow her to walk out of the cage and onto the frames of the new brood chamber. So in order, from bottom to top you will have:-
Floor; Brood box with brood and bees and no queen; Queen excluder; New brood box with queen and some of the comb drawn; Crown Board; Feeder with empty super around; roof.
If there is plenty of nectar coming in, you may not need to feed over the next week. However you now have the queen upstairs and the bees will start to work to enable her to lay in the new comb. Leave for another week or so. When you inspect you may be disappointed that there is not wall to wall brood but remember that the bulk of the bees are with the brood in the lower box so it can take a while to really get going; although I would expect the queen to be laying evidenced by the presence of eggs and small larvae. You should be able to find the queen fairly easily as there is usually not a huge number of bees in the top box at this time. If you moved an old brood frame up, then now is the time to move it down - without the queen of course. It's also the time to add the eke over the queen excluder. This means that the queen is in the top box with brood. The flyers are now able to enter by the top entrance in the eke and you now need to close off the lower entrance. It will take a little while for the bees to work out that they need to use the top entrance, but they will. So in order, you will now have:-
Closed off floor; Brood box with brood and bees and no queen; Queen excluder; Eke and entrance; New brood box with some drawn comb and queen; crown board; feeder with empty super around; roof.
The colony can now be left until all the brood has emerged in the lower box. This will be 3 weeks if you moved (a frame of) brood up with the queen or 2 weeks if you didn't. Why the top entrance? The reason is that bees like to have food above them and not below, so they will tend to remove food from the lower frames and bring it up and around the brood-nest. So what we hope is that they have cleared out the old frames for you with little or no wastage! (This is also a technique of getting bees to clean-out a part-used super as they don't like food under the brood-nest).
Once there is no brood and quite possibly little food in the lower box, it can be removed along with the eke and queen excluder and the lower entrance restored. If there is more foundation to draw, you may wish to feed - and in autumn you will want the hive to be full of stores in any case. With the old comb and pathogens gone, it is said that bees on new comb do well and can overtake a colony that has been kept on old comb even though it has had to create all new. What do you think?
What to do with old comb? It's tempting to keep it 'just in case' but that will usually mean that you use it yet again in an emergency so the best thing is to melt it down or dispose of it as soon as possible! You might want to keep a couple of the better frames for use in a bait hive. Old comb can be useful as a firelighter for a fire or chimnea or fire-pit too. Very old combs will give you almost no wax and a lot of mess trying to obtain it so it's probably not worth the bother trying.