After the problems I've had queen rearing this year, I ended up getting a couple of queens from a friend of mine. I prepared the two hives 24 hours before hand by removing the drone laying queens from both. At the same time I made a nuc with purely nurse bees from two of my good strong colonies to combine with one of the now queenless hives, I shook in 5 frames of bees which were on brood frames with eggs and larvae and waited 20 minutes for the mature bees to find the entrance and fly back to their normal hives. I sealed the entrance then moved them to my other apiary. Late the next day I put in a queen cage with the candy cap still sealed and left them for 3 days before returning and removing the cap to give the queen the best chance of being accepted before she was released from her cage.
Another 3 days later I was checking one of my other hives when I saw what seemed a non-stop flow of wasps entering the nurse bee nuc to rob it. I opened the nuc to find hundreds of bees and about 30 wasps dead inside but thankfully the queen and about 200 bees were still alive. My only option was to capture the queen in a queen clip and shake remaining live bees out into the queenless hive I was going to combine them with and coat the queen clip and the whole colony with lots of powdered sugar.
3 days later I released the queen from the clip and she calmly walked down between two frames, I will check in two weeks time to see if she has started to lay or if she was attacked and killed.
Last year I only had a minor problem with wasps, but this year it has become a major problem at one of my apiaries. I have had to close down the entrances to a narrow slot on all the hives even though some of them are strong the wasps seem desperate to get in. If the problem continues I may need to fit a plate loosely over the entrance to confuse the attackers how to get in.
All in all, this year hasn't been to good with the problems I've had and the long spells of hot weather and very little rain which has badly affected the nectar flow.