I’ll admit it, I’m a bit of a snob when it comes to joinery for furniture. I learned to make furniture the old way, using traditional joinery, like mortise & tenon, dovetails, dados, etc. I don’t own a Festool Domino, and I have no plans to invest in one. I’ve never used loose tenon joinery made with a router. I’ve never built a piece of furniture using pocket screws for structural elements (though I have used pocket screws for other tasks). I don’t have anything against these construction methods, I simply prefer to make and use traditional joinery.
So it was with some hesitation that I approached the joinery in two of my most recent projects. I knew in my heart of hearts that traditional drawbored mortise and tenon would be the absolute strongest way to join the parts of the pieces I was making. I also knew that if I chose to go the route of using traditional mortise and tenon that I’d have to make and fit over 60 of them, which would be a serious time commitment, and I needed to get these pieces done in a reasonable amount of time while juggling several other projects.
An additional consideration was that the beds I was making were for my daughters, and they wanted to be involved in building them. At this point, I didn’t feel that they were ready to learn hand cut mortise and tenon joinery. Trying to teach them to make this joint at this point in their journey would likely be nothing but a lesson in frustration for all of us. They just wanted their new beds, they aren’t yet interested in the finer points of hand made joinery. So if the joinery were to take too long or be too much of a challenge for them to execute well enough for the beds (and repeat it 30 times each), they’d likely just get bored and walk away.
So, while the mortise and tenon would have been the absolute strongest way to join the parts, I had to take a step back and ask myself if the project really needed the strength that the mortise and tenon would provide. My goal was to avoid frustration and make building these beds as enjoyable a process as possible, for all of us. That meant that the process couldn’t be too slow or tedious. I needed to keep the girls’ attention during the build, but still make the beds strong enough to last their lifetime. In my mind, dowel joinery was a good compromise between speed and strength.
Dowel joinery gets a bad reputation due to the cheap way in which they are used in mass produced factory furniture. Make no mistake, if not used appropriately, dowel joints will fail catastrophically in short order. Round mortise and round tenon is one of the weakest joints you can use when the joint will be placed in tension. If you don’t believe me, just look at all of the failed factory Windsor style chairs that end up on the curb of almost every home in suburban America. In most of them, the stretchers just pull out of the legs as the factory does not use enough glue, they put the stretchers in tension between the legs, and the glue surface inside the mortise is all end grain. Anyone who knows anything about woodworking knows that an end grain glue joint will survive only until it is placed under stress. It’s not a viable joint and it will fail.
However, dowel joints are quite strong in shear (stress placed across the dowel), especially if the dowels are large enough, and enough of them are used. Just consider all of the drawbored mortise and tenons that have survived without glue for hundreds of years. In most of them, the drawbore peg remains completely intact and keeps the tenon tight in its mortise.
So for these beds, I was confident that dowels would be completely adequate for the application. In the case of the rails in the head boards and foot boards, I used five 3/8″ diameter oak dowels in each joint. Considering that an integral tenon in this case would have been made of soft white pine, one might argue that the oak dowels might be even stronger. However, there should be no reason that this is ever put to test. Further, these joints will never be put into tension as the weight of the mattress and sleeper will be straight down, across the grain of the 10 dowels. Additionally, the side rails, which will likely carry the majority of the weight anyway, are joined to the legs of the head boards and foot boards using steel bed rail brackets, so the legs will actually support the majority of the weight, not the dowels.
By using dowels in this application, my daughters and I were able to complete these two beds in just a couple of weeks from the first saw cut to the final assembly in their bedrooms. Everyone enjoyed the project and stayed engaged in the builds until the very end. Further, I am confident that these beds will last them at least their lifetimes, if not longer. In the end, everyone was happy, and that means the project was a success!