Building a swarm trap is quite easy. This article describes how I build mine. These are Top Bar hives, making transfer to a larger hive very easy. I am assuming here that anyone following these instructions has cut the lumber so that the pieces are all cut to size and ready to assemble.
There are two steps that can be done first. I do either first, but both must be done before the rest of the steps are done. I like to start with attaching the 2×2 supports to the sides. So that will be step 1….
1. Attach the 2×2 supports to the sides. Place a 2×2 support on a bench or table. Stand a side on the shorter edge against the 2×2 support and clamp the two pieces together. By doing this, the two pieces should be square and flush.

The side and support pieces.

Align the side and support.

Clamp the side and support together.

Support the other end of the side.
Drill and countersink through the side into the 2×2 support. Countersinking is necessary so to make the inside of the hive smooth so comb can be cut from the sides if necessary. If you want to use glue, separate the pieces and apply the glue. Then screw the two pieces together. Repeat this process on the other end of the side, then repeat it for the second side. Make sure the 2×2 support does not cover the entrance hole. A shorter 2×2 support may be needed for the southeast edge because of the entrance hole, however, if the hole is in the correct spot, it should not be a problem.

Drill and countersink the side.

The drilled side.

Attach side with screws.

Align side and second support.

Clamp second side and support.

The completed side.

Both completed sides.
2. Draw the inside shape of the hive on each end. I start with the West End. I use a pattern piece cut using my hive jig (Described in Hive Jig on November 23, 2011. However, I also draw the entire inside pattern on the end pieces to make sure it all goes together correctly. Small errors can make a big difference in the hive dimensions. I mark the center of the pattern and the West End piece. Draw a center line and then measure and draw the pattern to the correct dimensions. Remember, on the West End piece, the top width of the inside is 18 5/8 inches, the bottom width is 7 3/8 inches and distance from top to bottom is 9 3/4 inches. On the East End, the width at the top of the inside is 19 1/2 inches, the bottom width is still 7 3/8 inches and the distance from top to bottom is 10 1/2 inches. This should be very carefully drawn out.

Draw the hive pattern on the inside of the end.

Complete drawing the hive pattern on the inside of the end.

The drawn pattern.
3. Attach the bottom board to the ends. First drill three holes in each end where the bottom board will be attached. Carefully align the top of the bottom board with bottom of the inside of the hive as drawn on the end pieces. Once it is aligned perfectly, drill through one of the existing holes in the end and attach the end to the bottom with a screw. Check the alignment and drill through the other holes into the bottom board and finish attaching the bottom to the end piece. Clamp the pattern to the other end piece and use it to hold up the bottom board. Align the bottom with the drawing on the end piece and attach the bottom board to this end. As with the other joints, glue may be used if desired once the pieces are properly aligned.

The bottom board, showing the correct shape.

Drilling the bottom board.

Attaching the bottom with one screw.

Aligning the bottom before adding more screws.

Attach aligned bottom with more screws.

Attach the bottom to the other end.
4. Attach the south side. Rest the hive on it’s bottom. Determine which side is the south side. The south side has an entrance in it. Actually I like to drill the entrance once the south side is installed from the inside. Turn the hive over so it is resting on the north side. Place one the sides on the bottom board and align the other edge with the pattern on the south side of the West End. The edge of the top of the side should be flush with the top of the West End. Flip the hive over so the widest part is down. Put a piece of 1x lumber under the west end and the side, and under the side only at the east end. The East End should be touching the table. Adjust the side so that both the side and the West End are touching the 1x lumber holding them up when the side is aligned with the drawn pattern on the West End. Make sure the side is also touching the bottom. Clamp the side to the West End. Attach the side to the West End. Check the alignment of the side on the East End. Make any corrections needed and clamp the side to the East End and attach it. Drill through the sides into the bottom board and attach the side to the bottom board. You might have to drill through the sides at an angle to hit the bottom board. To do this, drill about 1/16 inch straight into the side and then change the angle of the drill with the drill running. Once the south side is attached, drill the entrance hole from the inside if it has not been drilled already.

Drilling the end and side with the side clamped to the end.

Clamp the side to the East End.

Attach the side to the East End.
5. Attach the other side. Align and clamp the side to both ends, making sure it is against the bottom and flush with the top, aligned with the pattern correctly. Make sure that the hive entrance is in the Southeast corner of the hive. This is very important. Bees like the entrance in the lower south east corner of the hive. Since the hive is upside down and we are going to flip the hive over, the entrance hole should be at the top.
6. Attach hardware cloth over the inside of the entrance. A two inch square piece of 1/2 inch hardware cloth is attached with staples to the inside of the hive over the entrance to prevent birds and mice from getting into the hive. This won’t bother the bees a bit.
7. Drill ventilation holes. Drill between 4 and 6 ventilation holes using a 1/8 or 3/16 drill bit into the ends just above the bottom board for ventilation of the hive. The bees will plug any they don’t want. These ventilation holes won’t affect the bees decision to bring the swarm to the trap, so more is probably better than less.

The completed trap.
8. Attach the lid. The lid is just a piece of plywood. I like to be able to attach it over the top bars, or possibly without the top bars if I am using it to capture a swarm. I put a screw or an eye screw into the top and the ends so I can fasten the lid to the hive body with a bungee cord, strong rubber bands or even rope or string.
The hive body is complete. I recommend painting the outside of the hive with a relatively dark color to help camouflage the hive. The bees won’t care, but if it is less visible to humans, that is better. You don’t want people messing with your swarm traps. I recommend using an oil based primer and then coating the hive with an oil based paint. If you can get some mistakes from your local paint store, this can be an inexpensive way to get paint. The paint helps protect the swarm trap from the elements.
These hives are now ready to deploy. If placed on flat roof tops or on flat branches, they are fine as they are. If placed in a tree, a method for hanging the hive in the tree will be needed. For both deployment options, the 2×8 bottom provides a strong foundation to the hive. The tree hanger and deployment is a topic for another blog.
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