CARPENTER BEE TRAPS - Optimized Design

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Project by FuzzyDove posted 03-24-2017 04:11 PM 9665 views 14 times favorited 14 comments Add to Favorites Watch

With my youngest son heading to college in the Fall, we came up with a project that he could build and sell at the local farmer’s market for pocket money. My house has a lot of exposed wood and carpenter bees are a huge problem. I’ve experimented in the past with lots of different designs (see Photo 5), but my final design is optimal on so many levels. It uses the least amount of cedar possible, can be built with limited tool set up, uses no nails/screws, is small in scale, and works with any bottle that has a standard plastic soda bottle screw top (square fuji water bottles look the best). For those not familiar, carpenter bees go in the 1/2” holes that are at a 45 deg angle and protected by an overhang (they are lazy and prefer to use existing holes instead of making new ones), but once inside they only see light at the bottom bottle hole opening which they go to as an exit, only to discover that they are trapped (they can’t figure out how to get back up and out). The traps work best once the first bee is caught because the stressed bee releases pheromones that attract subsequent bees. It is important to leave the wood untreated because the bees are less attracted to treated wood – hence, cedar is a great outdoor wood choice (plus the bees like the rougher texture). With this design you only need standard cedar that can be bought in any big box hardware (I used cedar fence pickets for the roofs to further reduce costs). When installing the brass hook on top, we pre-drilled tiny holes, added a few drops of water, then dipped the brass hook screw in Gorilla glue before screwing in. That ensures a lifetime of strength for the hook because of the expanding nature of Gorilla glue where there is moisture. One key item that you will need for this design is a 30mm forstner bit to create the hole that a soda bottle cap (which has had the middle of it drilled out with a 3/4” drill bit) goes into and is also glued with expanding Gorilla glue. We also found that building a little 45 deg sled for drilling the bee holes saved a lot of time (sled works on both a 45 deg and 22.5 deg setting for the angled sides). Other design spec/details are in the picture of my pencil notes. Overall, we have about $4 in materials in each finished trap. I can say, we hung a few a couple days ago and are already catching some!
Busy as a bee,
(Below is a copy/paste from an email that I sent to a fellow LumberJock who was going to build some traps. It should provide most required info)

1) When cutting the bodies, set your miter saw to the right side at 22.5deg. After the first cut (you will have a little waste with first cut because the board is presumably 90 deg to start), FLIP THE BOARD, and make a pencil mark on your saw fence to indicate where to cut to make the longest side 6.5”. Then make another mark so that the next cut is the same width as the board thickness (13/16” usually), which is one of the side wall centers. Now, Just FLIP THE BOARD and repeat the two cuts for as many traps as you are building or until you are out of board. The pencil marks and flipping make for very quick work of cutting the bodies.

2) For the angled holes, take the time to build a sled with alignment slots as shown in the pictures. One sled will allow for both drilling angles (holes are 45deg but since the L/R sides are already angled at 22.5deg, you drill those at the same to sum up to 45deg). NOTE: you can drill the front/back before or after assembly of the body (I prefer before), but do not try to drill the L/R side holes until after assembly of the body. Oh, also, I find that a 1/2” forstner bit creates a much cleaner hole (in soft cedar anyway) compared to a standard drill bit.

3) Since you are going to assemble with an air nailer, pay attention to not put any stables where the drilled holes would hit the nails.

4) I use a belt sander/jointer to even up the assembled bodies, but if you are going for volume it should be fine without if your cuts were consistent.

5) Cutting the roof stock and its angles is pretty straight forward. I cut the full length board angles on my table saw, then cut the short sides on my miter saw using pencil marks on the fence just like we did for the bodies but this time, when you make the second cut, both FLIP and SPIN 180deg the board so the drip line angle is correct.

6) I actually joint the bottom of the roofs and belt sand the top of the bodies to assume a perfect fit, but that is optional. You should build a little jig to center the roofs before air nailing on…. that would be a real time saver.

7) I did not take a picture of how I drilled the hole in the plastic bottle tops. Take the time to build a box that a soda bottle snugly fits in, then add water/expanding glue to get that bottle rock solid in the box. Now you can clamp the box in your drill press and safely bore out bottle caps. Without the box, it is a bit dangerous because there is no easy way to safely hold a round-ish soft plastic bottle in place. I’m sure there are other ways of doing it, perhaps with just the cap being clamped, but whatever works safely. I used just a full 3/4” drill bit to bore out the holes and it works great once you get it set up and centered perfectly.

8) On the hole on the bottom of the body that will receive the bottle cap, you must use a 30mm forstner bit and drill to a depth of just a tad deeper than the height of a bottle cap. You will actually be drilling into a rectangular opening, but don’t let that concern you – the 30mm diameter hole is slightly larger than the long side of the rectangular opening.

9) When gluing the bottle cap in the hole in the bottom of the body, it is critical to wet the hole with a little water and use expanding Gorilla glue.

And from the start of the write up:
Wood Stock Required: Do NOT stain or paint the wood as the bees are only attracted to unfinished wood. A softer wood is preferred by the bees as well, so a good outdoor-durable choice is cedar or cypress, but inexpensive pine is fine, it just will not hold up well in the elements. Despite the “wet dog” odor when cutting/sanding, regular cedar that is available at any big box hardware like Lowes/Home Depot, is what I use. For the box bodies, just buy one board of 1” x 6” x 8’ [nominal/actual thickness varies by store/lot but is generally either 13/16” or 7/8” thick]. In general, only the first/last cuts yield any waste, so and 8 foot long board will easily yield 7 trap bodies (8 is possible if no knots or mistakes). If you are only making one trap, the minimum length for the body stock is 13.25” long. For the trap roofs, I use the less expensive cedar fence pickets (in the garden center at Lowes instead of with the other lumber) which are size as 5/8” x 5-1/2” x 6’. Each 6’ picket will yield about 8 roof tops.

14 comments so far

View frankie voyles's profile

frankie voyles

128 posts in 2071 days

#1 posted 03-24-2017 04:17 PM

cool. it’s time to put them out in sc.

-- frankie v

View cmmyakman's profile


346 posts in 3871 days

#2 posted 03-24-2017 08:42 PM

Very cool. I don’t have a carpenter bee problem, but I did, I’d appreciate all of the engineering and research you put into this project.

-- You can't fail if you don't give up.

View Desert_Woodworker's profile (online now)


7982 posts in 2429 days

#3 posted 03-25-2017 02:26 AM

Auchwitz for the bee’s :( If a person wants to kill life then do it in a humane way. This is as sick as the electrontric mosquito zappers in the 1970’s designed to stop mosquito’s but they didn’t- they killed the other non bothersome insects.. Terrible project why not use Kyklon B like the Nazi’s Yes I experience “bee” invasions around my home but to go to the extremes as a woodworker to make and profit from extermination and to sell them for $$$ :(

-- Desert_Woodworker

View leafherder's profile


1986 posts in 3167 days

#4 posted 03-25-2017 01:18 PM

I know how damaging a carpenter bee infestation can be. Anything that can alleviate the problem without using dangerous chemicals that can harm humans, animals and plants is worth the money. I also like the fact that this project is environmentally friendly by using renewable resources (wood) and promotes recycling by reusing plastic bottles. Thank you for posting.

-- Leafherder

View Mainiac Matt 's profile

Mainiac Matt

9972 posts in 3543 days

#5 posted 03-25-2017 01:45 PM

Fuzzy Dove… Great project. Very clever.

Desert_Woodworker…. Please stay in the desert, you appear well suited for it.

-- Matt -- I yam what I yam and that's all what I yam

View oldrivers's profile


2708 posts in 2781 days

#6 posted 03-25-2017 06:53 PM

Very neat project, congrats on the Daily top 3 you did a great job. What is the market price for one of the traps?

-- Soli Deo gloria!

View propcarver's profile


33 posts in 5044 days

#7 posted 03-26-2017 09:52 AM

Nice Job. I’ve fought the battle with these pests for years. The bee trap is the only solution that works.

To Desert_Woodworker
I took a look at your blog. Over a year ago you said ”many of the Big names have left (including me, or soon to) ”. Why are you still here?

I’m sure the Anti-Defamation League will be happy to assist you with the proper spelling of “Auschwitz” and the actual facts surrounding the events referred to as “The Holocaust”.

View recycle1943's profile


5813 posts in 2837 days

#8 posted 03-26-2017 12:06 PM

FuzzyDove – GREAT job, my only criticism is that I can’t copy your drawing. How am I supposed to copy your idea if you don’t publish printable diagrams ? ( LOL )

@Desert_woodworker – WHAT ??

-- Dick, Malvern Ohio - my biggest fear is that when I die, my wife sells my toys for what I told her I paid for them

View oldguy2's profile


330 posts in 2642 days

#9 posted 03-26-2017 04:39 PM

Thanks. Simple idea and very workable. Nice to think about a sell-able product also.

View dublittle's profile


1 post in 1640 days

#10 posted 03-27-2017 06:12 PM

I really like this trap and would like to make a couple to use around my house but like recycle1943, I cannot read your drawing. Can you send me a message with it attached? (Or publish a clearer copy) TIA

View FuzzyDove's profile


64 posts in 4589 days

#11 posted 03-28-2017 10:52 AM

Thanks everyone for the support and positive feedback, especially those who rallied against the negative babble of over opinionated gadflies. I now realize the picture of my notes lost resolution when I uploaded it to LumberJocks, so I’m working on writing up detailed instructions that I can email directly to those who are interested (just go to my profile and send me a message with an email address for me to send the instructions to).

View recycle1943's profile


5813 posts in 2837 days

#12 posted 03-28-2017 03:31 PM

just sent a pm
btw – congrats on the top 3 recognition

-- Dick, Malvern Ohio - my biggest fear is that when I die, my wife sells my toys for what I told her I paid for them

View SpecialK's profile


1 post in 2223 days

#13 posted 04-01-2017 12:19 PM

Great job. My 4yr old (HD Kids workshop regular) would love to help with this project. I don’t have enough posts to pm you, so you see this and don’t mind, we’d love the instructions. Our bees are constantly destroying our deck and are eyeing the brand new swing set. Thanks!

View Winnie208's profile


1 post in 1593 days

#14 posted 05-13-2017 11:00 PM

These would help our carpenter bee problem. Great looking project. I am new to your blog and would love to have the drawings and instructions. Thanks again

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