Carpenter Bee Traps

Carpenter Bee Trap Plans

By Jim MacLachlan


Copyright 2017 by Jim MacLachlan

Published by Jim MacLachlan at Shakespir

Shakespir Edition License Notes

This ebook is licensed for your personal enjoyment only, but you can freely distribute this document. It’s freely available to anyone who wants to use it in multiple formats. Feel free to edit it to meet your needs, but don’t resell it & please keep the proper attribution.


[]Warnings & Disclaimers

READ THIS. I’m serious.

Use of any & all construction methods I describe or you think I allude to is at your own risk. I may use shorthand or do things that are dangerous. I’m not writing safety instructions since I don’t know what tools you’re using, your age, strength, or skill level.

Working with wood is inherently dangerous. Anyone using any of the tools or techniques in this book is personally responsible for learning the proper methods involved. You assume all risks and accept complete responsibility for any and all damages and injury of any kind, including death, which may result.

Before using any hand or power tool with which you are unfamiliar, consult its operating instructions, and if necessary, seek instruction by a qualified person well versed in its operation and appropriate safety techniques. It remains up to you to make sure what you’re doing is safe. The joy of woodworking, rewarding as it is, is not worth the cost of getting hurt. Please keep safety foremost in your mind whenever you’re in the shop.

In simpler words, if you hurt yourself based on anything in this document, that’s your responsibility.


By reading further, you agree to the above.


I may include hyperlinks to outside sites & articles. I tried to only use stable, safe sites, but click on them at your own risk. Things change rapidly on the Internet & are beyond my control.

[]Table of Contents

Carpenter Bee Trap Plans (top)

Warnings & Disclaimers

Table Of Contents

Key Terms

The Basics

Tools & Materials Needed

2×4 Carpenter Bee Trap

Log Carpenter Bee Trap


[]Key Terms

All measurements are in SAE units. There aren’t many & few are critical in this project. I live in the US where we still haven’t changed to metric for most things, especially not woodworking save for manufactured wood products we buy from overseas such as plywood. I have no knowledge of standard metric sizes in woodworking. For instance, I don’t know if most woodworkers use a 12.5mm or 13mm drill bit for 1/2”, so I don’t bother to try to convert anything to metric.

I was deliberately casual in the way I wrote this & use common terminology. If you’re new to woodworking, this should help you better understand how informal plans & ideas are presented on message boards & in speech.

1” = One inch

1’ = One foot or 12 inches

1-1/2” = One & one half inch, the same as 1.5”, but decimals are rarely used with SAE board measurements since fractions convert easier & are what our tape measures show.

A common board is a construction grade 2×4-8. That is nominally 2” thick by 4” wide by 8’ long. The dimensions are given in that order & the units are assumed unless otherwise specified. That’s only the nominal size of the board, the size when originally sawn. It was then dried which means it got smaller. It was then planed to even it out, so its actual size is 1-1/2”×3-1/2”-8’ when you buy it from a lumberyard. Each species will vary in how much it shrinks. All wood shrinks more up & down through the grain (radial) than across the grain (tangential) & very little lengthwise (longitudinally), & then most is finished to a standard size. The Wood Database explains it well & has a picture [+ here+] & Pro Wood has a handy chart of the actual dimensions [+ here+].


Read through the entire document before building one of these. There isn’t anything complicated or precise about them, but you’ll find that once you understand the basic concepts, you can adapt your materials & tools easily.

[]The Basics

Carpenter bees look similar to big bumblebees & they’re pretty innocuous for the most part. They rarely sting since we mostly see the males & they can’t; only the females can & they generally won’t. Like most bees, they’re an important part of the ecosystem, so I don’t go out of my way to kill them unless they’re causing a problem, which they certainly do when they build their nests in my buildings.

What I generally see is the 5/8” diameter hole they bore into almost any wood. A single hole isn’t that big a deal, although multiple holes can be a problem & are unsightly. The big issue comes from what I generally can’t see; the tunnel that the small hole leads into. These tunnels can be several feet in length & seriously weaken wood.

For example, my mother had a CCA treated 2x4-16' holding up netting over a chicken run that broke in half seemingly under its own weight. The fracture occurred between the openings for two borer bee holes near the center that we'd never even noticed before. I cut it up & found several tunnels running for 2' -3' along the length in opposite directions. They came very close to crossing each other several times near the openings, so close that I was surprised the board held as long as it did. So when I see them boring into the overhang of my shop, porch, or handrails, it's time to get rid of them.

I don’t like using pesticides & many aren’t particularly effective since the bees don’t eat the wood they’re boring into. They just crunch it into sawdust & shove it out the hole which is why they’ll bore into treated wood. Effective pesticides are pretty nasty & only work for a short time, so I think the best way to stop them is to plug their holes & trap them. That kills just those that are being a pest. Occasionally other bees will get trapped, but not many.

I give them several carpenter bee traps to crawl into; nice chunks of wood with premade holes that lead to a glass jar. They land on the outside of it, climb up into a tunnel that leads up at about a 45° angle to another that goes straight down through a jar lid into daylight. Unfortunately for them, they’re stuck in the jar until I get around to emptying it & killing them. I’ve never seen one find its way back out.



The trap needs to be hung during the few months in the late spring through early summer that the bees are actively trying to nest. I put up several traps in an area since their preferences vary & if one bee is using a hole, another usually won’t enter. They’re cheap & easy enough to make that multiples aren’t a problem. Likely spots are where ever they’re normally active, but try to keep them out of direct sunlight as much as possible since they won’t go into one that is too hot. The traps don’t have to be particularly well sheltered, but bees don’t want to nest in wet wood, so I seal the top of the trap with wax or paint & try to hang them under overhangs such as the edge of a porch roof. The top of the trap is the most porous area, so I generally leave the rest natural. I occasionally paint them, but I keep it out of the holes. They generally don’t like freshly painted surfaces since they need to land on the trap before walking into the hole.

I don’t’ put anything in the jar, although I know some people have put an inch or two of water in them. I think that just makes a mess & it can be really nasty if a few days go by between cleanings. (Hot weather stewed bees. Yuck!) I don’t know if it does anything to the effectiveness of the trap or not, though. I never use any sort of pesticide & clean the jar if it gets dirty or stinky at all.

I try to check the traps daily & empty them. I take the trap down & hold it close to the deck. Then I unscrew the lid & quickly turn the jar upside down. Usually the bees fall right down & I squish them with my shoe. Sometimes one or two will stay up in the jar, but I can usually knock or shake them down easily enough.

Some still bore holes. In that case, I plug them with [+ a toothpaste sized tube of Liquid Nails+], a construction adhesive. The end of the small tube fits into their hole well & I just squeeze in a good glob. A bit will bulge out, but that’s easy to cut off once it is dry, although I rarely bother since it is a tan color very similar to the 2×4’s under my shop’s overhang. On the porches, it doesn’t match well, but the holes are small & usually under railings & other places that can’t be seen easily. The tube reseals well with a screw top & is cheap enough that I keep a couple of tubes in likely places. They don’t seem to freeze, but I keep them out of direct sun & I’ve had some around for a few years. I often seal bees & their eggs inside the holes, but I never see any come back out. I guess the volatiles are nasty enough to kill them off. That’s fine with me.


[]Tools & Materials Needed

Few tools are needed to shape the basic pieces, but it varies a bit depending on the style you’re making. A drill with 5/8” & 3/4” paddle (spade) bits is necessary for drilling the bee holes. The 5/8” bit can be used for the top of the jar lid, but it won’t be much good in wood after that, so I keep one just for that chore & another for boring into wood. A 5/32” twist bit is nice for drilling the pilot hole for the hook, if you use the size I recommend.

The jar can be almost any size from 8 oz. to a quart, but it has to be clear glass with a lid. I wouldn’t trust bees not to gnaw their way out of plastic & any coloring would probably lessen their desire to go down into the jar. I don’t know the latter for a fact, though. It could be that some color would attract them, but I’ve never read or heard of such. I was given a bunch of quart Mason jars without lids that I’ve been using lately, but I’ve used pickle, relish, jelly, & other jars over the years. The bees are seemingly unable to get out of the hole in the lid. They seem to need to land & then crawl into a hole. While they can get into a vertical hole in wood, the smooth metal of the jar lid affords them no foothold.

Short, small screws are used to hold the jar lid to the base of the wooden piece. I generally use 1” drywall screws (#6), but most any screw about 3/4” long will do.

To seal the top against moisture, I either put on a coat of paint or wax. The wax is just paraffin sold at the grocery store for sealing jelly jars & I use a heat gun to melt it on.

The body of the trap can be made with any short (8”-10”) chunk of wood that is roughly round & roughly 4” in diameter for the log type. The other sort is made from 2 scraps of 2×4s about 8” long. Those are common, cheap, & easy to find on most construction job sites. I provide plans for using both.

I don’t like water to sit on the top of the trap, so I use a lathe to turn down the tops of logs. I suppose a chop saw could cut an angle on them, but that could be dangerous. A chop saw is perfect for cutting the 2×4’s to length & angling the tops, although a handsaw will work well, too.

If you’re using pieces of 2×4, a screwgun with four 2-1/2” treated deck screws is handy for putting them together. You can screw them in by hand or use nails, but I don’t recommend just using glue. It would probably hold together a few years, but if it fails, the jar will drop & break; a mess.


[]2×4 Carpenter Bee Trap

Find a couple of scraps of 2×4 about 8” long. I prefer SPF, the type used in interior house construction. You can even splurge & buy a brand new one for about $3.50 at any store that sells lumber or use a piece of 4×4, but I just use pieces I have left over from other projects. The 2×4 scrap I start with here is a bit over 16” long.



I marked it up to cut two 8” pieces.



IF you are using the full width of the 2×4, find the center line of the face (1-3/4”) run it up the entire length & across both ends. Cross it with lines at 1-1/2” from either end. I used a scribe to do both.


If you’d prefer your bee trap to be square, you’ll need to rip the 2×4’s to 3” wide.




Find the center line of the face (1-1/2”) & run a line at that distance up the entire length & across both ends. Cross it with lines at 1-1/2” from either end. I used a scribe to draw all the lines on both pieces of 2×4. On the right side, which will be the top, I marked in another 1-1/2”. That’s not strictly necessary, but it’s about where I want the top of the center hole to end.



I’ve marked where I’ll drill the holes & put an X where the screws will go to hold the 2 pieces together. They keep the screws well clear of the holes we’ll bore. On the right, I’ve marked the angle I’ll cut the top.



I drilled 1/8” holes into the top 2×4 & then screwed them together with 2-1/2” treated deck screws.



Here’s how we’re going to bore the bee trap. The center spade bit should actually drill in until the wings are even with the mark, not the point as shown in the picture. That’s just about the entire length of the bit. The 5/8” bit is used to drill the angled side holes, but you can use the 3/4”. It’s just a little harder to angle & drill, but it might be better if you plan to paint the trap since it will give the bees more room to land.



Clamp the pieces firmly with the bottom facing up. I’m using the vice at the end of my woodworking bench. The center is where my pencil mark meets the joint between the 2 boards.



Drill straight down the center. End grain drilling requires a sharp bit & tends to overheat it, so stop occasionally to let it cool off. Let the bit clear the hole of debris often. When you stop, check the depth by placing the bit against the outside of the 2×4’s. If anything, drill a bit too deep.



Drilling the holes that angle in to the center is a bit tougher. We need to start drilling in straight down & then angle the drill bit slowly to the correct angle. The block needs to be held solidly & you’ll need to keep a good grip on the drill. Keep the speed of the bit fast, & slowly angle the bit as you push in. On a soft 2×4, it’s really very easy once you’ve done it a time or two, but the first time can be a bit scary. Pick a place without any knots (They’re harder & more likely to catch.) for the first couple of holes until you get the hang of it.


Make sure the project is firmly held in the vice, get a good grip on the drill & start to drill in with the spade bit. It should have a long point as shown here:



That long point allows the bit to stay in the wood solidly when you start to angle it.



Keep the speed high as you slowly angle the bit.




I usually angle a bit more than I need to & then drill the hole in at the correct angle by eye. The hole should meet up with the center hole fully just before the mark as shown, but that means the side of the bit will encounter it much sooner. Once the hole is about halfway bored, the side of the paddle bit will start falling into the center hole so you’ll have to push forward harder & hold on to the drill tightly or it will get ripped right out of your hands.

Drill a hole in each side.



After all four side holes are drilled, look into them to make sure they’re clear. You’ll probably want to run the bit up them & the center hole again. Splinters & sawdust can get lodged in there & we want a clear path for the bees.


Now it’s time to get the jars ready. The left hand jar is an 8 oz. jam jar (strawberry, if it matters). The one on the right is a 32 oz (quart) Mason jar. I was given a box full (Yard sales are another good source.) & my wife picked up lids pretty cheap at the grocery store, but I don’t know the exact price. Either will work fine for this project since the lids are less than 3” in diameter.



Use an awl or a nail to poke a hole in the center. They’re thin, so I put the lid down on my wood benchtop & just push my sharp awl through. If you’re using a nail, a light tap with a hammer will do. You might want to use one of the 2×4s to support the lid. Don’t hold it in your hand! Both of these lids have a smaller circle in the center that made finding the center by eye easy.



Poke two more holes closer to the edge for the screws that will hold the lid to the base of the trap. These will also be used to hold the lid on a piece of scrap wood for drilling the center hole. I used 1” drywall screws into the piece scrap I cut off the edges of the 2×4 when I ripped it to 3” wide. Notice that I am drilling down, the direction the bee will be crawling. The drill bit will leave a burr & possibly some metal splinters on the lower edge (keep your fingers clear) but they will be pointing away from the bee’s direction of travel, so it won’t mind. You can use a file or some sandpaper to clean the hole up if you want.



This is going to dull the spade bit, so it won’t be good for boring wood again. It can be reused on more jar lids, though. Don’t try to drill too far through; just let the wings cut the metal free.



Remove the screws, put the lid together, & screw it on to the base of the bee trap. Make sure the center holes align, but they should do so easily since the hole in the trap is 3/4” while this one is only 5/8”.



I used a sliding miter (chop) saw to cut the bevels on the top, the end away from jar lid now. This could be done earlier, but I left it until I was sure everything else was going to work out & I stayed just off the lines I drew. The lines are for a perfect 45° angle that would make the top a point. I don’t really want a point since the next operation is drilling a pilot hole in the top for hook.



Drill a pilot hole in the top for a hook. The size will vary depending on the hook you use. I drilled a 5/32” hole for the #6 × 3-3/8” hooks I have going into the soft 2×4.



Screw the hook on & then the jar. The basic construction is done.



You can leave the trap unfinished, but I highly recommend sealing the top with something. Carpenter bees don’t want to go into a wet piece of wood & the tops of the 2×4s are amazingly porous. I melt paraffin wax on the top with a heat gun as often as not. In this case, I primed & then painted them.



Yeah, I suck at painting & picking colors. The paint was what I wanted to use up. Notice that I was careful not to get any in the trap holes, though. They need the rough wood to land on before they can enter the trap & they usually won’t chew through painted wood.


[]Log Carpenter Bee Trap

This form is for advanced woodworkers since it requires a lathe, most everything is done by eye, & it relies on instructions from the previous section.

I have a small woods & since the Emerald Ash Borer has killed off most of my ash trees, a lot of limbs available. I often use pieces of their limbs or others they crush as they fall to make carpenter bee traps if they’re about 4” in diameter. This is chunk of a walnut branch that came down in a storm. It’s about 5” in diameter & 8” long. I cut it on the chop saw to make sure both ends were smooth, but any saw can be used. The smoother the cut is, the better. Try to make sure the bottom is at 90° to the center line of the log. Remove all the loose bark that you can.



Poke a hole in the center of the lid with an awl, center the lid on both ends by eye, & drive the awl in a little to mark the center.

Optional: If you want to inset the jar lid into the base, draw a line around the jar lid so you’ll know the hole size.



Knock the drive spur into the bottom of the log.



Mount the log on the lathe. I cleaned off all the loose bark I could without digging holes in the side of the log. Still, once I started turning, more bark ripped free & flew around, so I try to stand to the side until it I think the rest is solid.



Turn the top into a smooth dome. There doesn’t need to be a lot of fall, we just don’t want water to sit on it.



Most of the bark came off this log now & the top is rounded enough. I think the bug trails are neat looking. If I tried harder to remove all the bark, I’d likely scar them, so I’d rather dodge the flying bark. Your call.


Optional: If you want to inset the jar lid into the bottom of the bee trap, reverse the log on the lathe. Knock the drive spur in as little as possible. Any dents it causes will catch water, unless they’re filled or sanded out. If you want to do this, leaving a slightly longer & larger tit when turning the top is a good idea.



Use a parting tool to cut the edges of the bottom hole & set the depth. It’s not a big deal if it is a little too deep.



Clean out the bottom to the desired depth. I like to hide the jar lid somewhat, but I don’t bother doing it entirely. Check that the lid fits & make sure the tit on the tailstock is less than 3/4” in diameter.



Mount the log securely in a vice & bore the bottom hole. I don’t bother marking a depth, just eyeball it. Look at the pictures of the 2×4 bee traps at the beginning of the document if you want to measure.



Once the center hole is drilled, I remount the log in the vice & drill the first side hole. Again, read the instructions for the 2×4 bee trap for measurements & instructions.



After the first side hole is drilled, I mark the others. Depending on the size of the log, knots, holes, & such, I may only drill a total of three, so I mark it accordingly on the bottom.



Mount the log back in the vice & drill the rest of the side holes.


Pull the log out of the vice & seal the top. I used paraffin wax that comes in blocks from the grocery store for sealing jellies. Use a heat gun on low to warm up the top of the log well first & then wipe the block around it. That lets the wax soak into the grain & I don’t worry much if some slops down the sides. Obviously, don’t get the top hot enough that you set fire to it & be careful when you set it down since you’ve got a lot of sawdust & other flammable stuff around.



Screw the lid on to the bottom. Pilot drill & put the hook into the top. Once the jar is screwed on to the bottom, the project is done.



There are a lot of plans available for trapping carpenter bees. I’m not sure where the idea for the ones I make came from, but I believe they’re common knowledge. A quick search will turn up many plans that are almost identical. I hope this helps beginning woodworkers & pointed out some different techniques or materials. While it was some work to create, I wouldn’t feel right charging anything for it.

If you find an error or have ideas & experiences to share, please email me at [email protected] or find me on GoodReads.com. We can discuss working more in the General Craft & DIY group there. Admission is free & I’ll try to answer questions, but please remember this is a hobby project done in my spare time.

If you enjoyed this, take a look at some of my other books on Shakespir.com.


Carpenter Bee Traps

Carpenter bees look similar to big bumblebees & they're pretty innocuous for the most part. Like most bees, they're an important part of the ecosystem, so I don't go out of my way to kill them unless they're causing a problem, which they certainly do when they build their nests in my buildings. I don't like using pesticides & many aren't particularly effective since the bees don't eat the wood they're boring into. They just crunch it into sawdust & shove it out the hole which is why they'll bore into treated wood. Effective pesticides are pretty nasty & only work for a short time, so I think the best way to stop them is to plug their holes & trap them. These are the plans for a couple of different traps; one using 2x4 scraps, the other a bit of tree branch. The basic idea is simple. The bees find a nice chunk of wood with premade holes that lead to a glass jar. They land on the outside of it, climb up into a tunnel that leads up at about a 45° angle to another that goes straight down through a jar lid into daylight. Unfortunately for them, they're stuck in the jar until I get around to emptying it & killing them. I've never seen one find its way back out.

  • Author: Jim MacLachlan
  • Published: 2017-09-01 17:35:11
  • Words: 4409
Carpenter Bee Traps Carpenter Bee Traps