Toshi-Nuki Shelves – Build 2

Following from the last post on building the Toshi-Nuki Shelves, which was mainly about cutting mortises, we continue on with… more mortises. Or in this case a few quick and simple mortises cut with the Festool Domino. I don’t own a Domino, but a friend of mine has one so I’ve been playing around with it here and there. I definitely wouldn’t give up traditional joinery in favor of one, but I’m beginning to appreciate the domino more and more for certain situations.

When designing this shelf, I decided to join the posts in pairs, using short rails going front to back. My plan for the posts was to make them round, so those short stretchers needed to have a matching round cut-out to cleanly join the round posts. If I had used traditional mortise and tenons to join the short rails and posts, it would have been a lot harder to cut out the round profile into the end of the rails, due to the tenon sticking out. So to make the whole process simpler I opted to use dominos. (if this all sounds a bit hazy, stay with me, and hopefully the process will start to make more sense as you see the process unfold).

You can see the domino mortises in a few of the posts below. Each post required 3 domino mortises.

With the last of the mortises cut, I could move ahead with making the posts round. The posts are about 1200 mm long (nearly 48″) and are a bit too long to turn on the lathe. I also didn’t have a router or large enough round-over bit handy, so I opted to use a combination of power and hand planes to make these round.

I started by making a simple jig to hold each post at a 45 degree angle.

Then I ran each post through the planer, taking off the corners until I was left with an even octagon shape..

Then I grabbed a power planer to take off the corners of the octagons. That little cutout on the front end of the planer works great for this kind of work. It’s easy to ride that cutout along the corner of the post and get even consistent cuts.

Here’s how things looked after taking off the corners of the octagon shaped posts.

Lastly I used a hand plane to take things a step further towards round by smoothing out the hard edges, and doing my best to get an even series of narrow facets flowing around each post. I used a flat plane for this. I could have used an uchi-maru-ganna 内丸鉋 (a Japanese plane for cutting a round profile) but I actually prefer the faceted texture you get from using a flat plane. I’ve done this now on a few different projects and I really like the result you get by leaving a faceted surface. All those little facets have a really subtle way of accentuating the linear flow of the grain when light hits the surface. It’s almost imperceptible, but it’s definitely different than a perfect round post. Flat planes are also so much easier to sharpen than round planes, so that’s another bonus to this approach.

With work on the posts more of less complete, I moved on to cutting the joinery in the long shelf supports. The long shelf supports pass through the posts, and are joined to the posts using the watari-ago joint (upper right in drawing below).

I previously milled the 6 shelf stretchers to width and thickness, but didn’t cut them to length. To ensure that these parts would all be the same length I ganged them up and clamped them together, while I cut them to length on the sliding table saw. From there I carefully kept the whole bundle together and proceeded to cut the notches that will mate with the watari-ago notches in the posts.

Here is one set of notches after roughing on the sliding table saw. This looks like one piece of wood, but it’s actually 6 pieces stacked together.

I used a trimmer to clean up the cut, and to establish the final depth of 6mm.

Next up I cut a rabbet down one side of each shelf support. These rabbets will house the actual shelf boards.

I used the groover for this work. The groover is messy and spews chips everywhere, but it’s quick and leaves a really clean cut.

One final step after running the groover, was to clean up the corners where the rabbet stops. I didn’t take detailed photos of the process but essentially I used a trimmer router to remove most of the waste, and then a chisel for the final clean up to leave a clean square corner.

Next up was the work on the short stretchers. These are the pieces that I mentioned in the beginning. They needed a round cutout on the end to mate with the round posts. Why not just cut a recess in the posts for these pieces to inset into? Mainly because gaps will be more visible that way. After handplaning the short stretchers there’s going to be a certain amount of inconsistency in their final size. Pairing that with a pre-cut recess in the post and there’s a good chance some gaps will show up. In general, with inset connections vs connections that butt into one another with a shoulder, the visibility of gaps will be less if you use a joint with a shoulder. I’ve been thinking about the carpentry work I did here in Japan over the past few years, and on very few occasions did we ever cut a visible joint that didn’t have a shoulder, and I think cleanliness and a gap-free finish are the driving factors there.

So that’s was my thinking for these joints as well. Nevertheless, making a round cut into the end of a piece of wood is not exactly a straightforward task. But I had one idea in mind that I wanted to try out, using a sharp forstner style bit to cut the end of the short stretchers. So I bought a 40 mm diameter bit to match the diameter of the posts, and made a really simple jig to hold the stretcher for cutting.

The jig is pretty simple. First I drilled a hole in piece of scrap with the 40mm diameter bit. Then I cut an opening, centered on the hole, just big enough to slide in a stretcher. From there I attached another piece to act as a fence, and to give me the ability to clamp the stretcher in place. The hole I drilled worked to not only align the stretcher for cutting, but also served to support the drill bit as it cut the end of the stretcher.

Here is the stretcher after drilling out the end. you can see my layout line, which just meets the bottom of the cut.

When all was said and done, the setup worked out pretty well. I only needed 9 stretchers but I cut a few extra pieces just in case I had any screw ups. The cut looks slightly rough in the picture below, but it was actually really clean. There was a slight bit of tear-out on the very bottom of the cut, but all of that disappeared later after handplaning. I have no association with the company, but I have to give a shout out to Star M bits, which is where I got the 40mm forstner bit. I’ve been consistently impressed by the quality of all their products (drill bits and hollow chisels for mortisers) and their ability to cut cleanly.

Next I cut domino mortises into both ends of each stretcher, to mate with the domino mortises I cut in the posts. I also used a soto-maru-nomi 外丸鑿 (lit. outside round chisel) for fine tuning the fit. The posts ended up close to 37 mm diameter and the bit I used above to cut the round on the stretcher was 40mm. So I pared away a tiny bit of the inside of the surface to get a better fit. I really didn’t need to remove too much material, so this process went pretty quick.

Then it was time to hand plane everything. Starting with the short stretchers.

I still get excited about plane shavings. There’s something magical about being able to take thin slices of wood, and seeing the grain structure and patterns that emerge.

Then I moved on to planing the long stretchers. A few of these pieces had some serious curly grain. It’s hard to get good images that really show what a difference hand planing makes. But after a few passes with the plane, these figured pieces really started to shine, and any trace of tearout from the milling phase of work disappeared. I don’t know if I’ll ever get tired of handplaning. It’s one of the most satisfying steps of the process.

After planing I moved on to gluing up the posts and short stretchers, using dominoes. I took a cue from my former shops mates in Brooklyn and made my own dominoes using some scrap pieces of cherry I had lying around.

Here is one of the post and stretcher assemblies after gluing. This was a pretty satisfying step, to finally see these little latters start to come together.

Here’s how the fit between the round posts and stretchers worked out. With a bit of clamp pressure any hint of gaps along the seams closed, making for a really clean fit. I really love the look of this kind of joint. Cutting joints like this takes a bit more effort to work out an effective process, but the result is worth it in my opinion.

Well, I thought I would be able to wrap up this project, but this post has gotten pretty long. So I’ll save the final details and finished images of the shelf for next week. Stay tuned, and thanks for reading.