Community challenge #6: Creative Joinery (closed)

No sorry, I didn’t mean the shaper origin - it’s a fun toy but frankly I don’t understand the point of a $2400 CNC machine where you have to be the gantry. I meant the new workstation thing they are pre-selling. I bet you could take some of the ideas in their design and make good use of them for vertical work holding on a Shapeoko.

Actually mentioned that on the team chat as well — at some point, I’m going to finish working through my backlog of joinery designs and projects and eventually will be revisiting:

which I’d like to remake in a version using a Hirth Coupling for positive angular locking at some number of degrees (radians?) which makes sense.


Hello fellow C3D fans!
I am beginning another CNC contest marathon lol, at the last minute I decided to go for it and with some very helpful advice, was able to come up with what I think is a decent design representing joinery, art, and a tribute to C3D at the same time.
I try to create intriguing objects that are unique, look good on a desk and use contrasting materials, and throwing in a bearing never hurts!
Looks like I might be able to get most of it done by the deadline if I go straight through to the end, who needs sleep! Or not… lol… zZZzzZzz
My first joinery project, will see how it goes! Check for updated pics on this reply as I progress.

After about 24 hours of machine time, things are going pretty well, a few mistakes were made…
My joinery fingers were kind of big, but fit my router bit to perfection, making cleanup on the bottom edges and tabs really easy.
I got dumb again and designed aluminum parts that need 2 mm end mills and multiple tool changes… Worked out fine though with a Carbide 3D bit #282-Z and a #112-Z.
Broke one of the spokes off my center joinery piece, no big deal glued it back on… Got 2 of my pieces backwards and did not notice the grains did not match until it was too late. Gorilla wood glue sets really fast!
Oh and I designed my joinery center part 1 inch too long to use the black walnut I had in stock so I used a piece of my mystery wood which is a funny story…

I was in a small local woodshop buying stock and I see these sections of really perfect dark reddish wood 1 inch thick no warp being prepped for another customer…
Me: Can I get some of that? Is it hardwood?
Woodguy: Yes and it is cheaper then Walnut.
Me: Can I get 8 feet in 18 inch sections please? Whats it called??
*Guy in background fires up a table saw RAAAAWWAAAAAAA
Mills great, beautiful stock almost perfect no warp, no idea what it is. Pic below.

-Shapeoko Video-

Progress pics:

Wow what a journey this one was! Very happy with the results! I think in the future I will hold off on the Marathon builds though haha… zZZZzzZzzz

Fusion Link


Hey Will, I have seen you link to that fixture for cutting vertical joint several times and just about every time I click the link to see how it works. But with the one picture I haven’t managed to grasp the concept…would you mind posting more pictures?
Plan to make one sometime and need ideas!

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Hello Everyone,
This is my first post and contest to C3D, so hopefully I get it right,
but I have seen the contest for awhile and figured since I have the time now why not. Besides I needed a tool and bit holder anyway and since that was my next thing on my list to make, why not give it a go, nothing special just something simple.

left side joinery.c2d (743.1 KB)
right side joinery.c2d (868.3 KB)


Wow very nice! One of the best I have ever seen, congratulations on a job well done!

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I second that, beautiful Job Travis!


Great design as always Max! Look forward to seeing the finished product.


Hi guys,

This contest immediately put my mind on some of the most amazing joinery out there, Japanese joinery! There are many to choose from but I wanted to commemorate one of the most mesmerizing joints to me and that’s the Kawai Tsugite joint.

There are some impossibilities to recreating the original joint since it was originally made with chisels that can achieve sharp inside corners that an end mill cannot recreate. I simplified the project to be CNC-able by removing the inside geometry and creating the joint in a cube instead of a longer piece of stock. I further simplified the joint for my own convenience by decreasing the height of the inside pockets so I could use the C3D #201 end mill without rubbing. After finishing the design, I decided to use two contrasting pieces of wood to really show off the joint to be a desk display piece. And what a great display piece it turned out to be.

The two pieces are rotationally symmetric and slot together in three orientations just like the traditional Kawai Tsugite joint. They are made from Walnut and Maple and are finished with mineral oil. Together, the cube is 1.9" square.

The process:
To create the parts, I started with a piece of Walnut from my scrap bin, and glued 3 pieces of .75" maple together to get a piece of maple at the right height (pretty funky piece of maple but… using what I’ve got at home). I chopped the cube stock up on my miter saw to get two 1.9" cubes to start with. I then 3D milled a fixture (out of some fine pine 2x4 to preserve my very scarce wood reserves) to orient the corner of the cubes for cnc milling. There were some issues here with the stock being so tall inside my fixture and I started my cnc milling off with a crash! The material was not lost though since I was removing all of that material anyway :stuck_out_tongue: …I then decided to split the file up into two steps so I could move the router up in the router mount to get enough height to clear away the corner material, and then back down and re-zero to do the pocket features.

This was such a great idea for a contest! I would’ve never thought to make a display piece for this awesome joint and now I cant stop playing with it XD

Here’s a video of the action:
compressed Kawai Tsugite (3.8 MB)

Files for the fixture and for the joint:
CNC (3.4 MB)


This project is actually the base for a iPad or tablet holder. However, having run out of material, time and design ideas for the addition bearings to the actual holder, I’ll have to call it good at this point. Hoping that @CNCInspiration will have bearing setup suggestions to share :wink:

Intending to use a .125 end mill allowing cutting through .750 material all of the joint corners needed to have their radius’s set to allow machining and final fitment without gaps. Creating a circle at .126 and doing a lot of boolean operations to smooth worked like a charm.

After spacing the joint components, they where joined using boolean operations to create the desired right side joint half. This was then copied and rotated 60 degrees opposite the first joint. To allow the finished pieces to join and allowing for glue, I then did an offset path of .002 to shrink the second half. Both halves were then boolean joined into a single 60 degree segment.

To check design fitment, I created five copies rotating each an additional 60 degrees and joined each at a common mid point.

I used to the default feeds and speeds for a .125 end mill in hardwood. Once cutting was underway I was able to comfortably raise this to 140% in Carbide Motion.

A measuring tool that not only does X, Y but also diagonal would be very helpful…please! Spacing the joint objects required a lot if creating blocks, rotating, resizing and repeating. I suppose a straight joint would be much simpler to achieve good spacing. Or being better at math than having been gifted with.

If you decide to use this tool path, use caution as there are no tabs. Instead I left an onion skin of .001-.002 by setting the Z to the machine bed then raising and resetting Z to the material thickness. Removing the skin only took a few strokes with 220 sandpaper.

The real test for the design and machining would be here, will the last piece fit? :
With only a few light taps with a block and mallet, success! This after the first finish coat of polyurethane:

7X5 60 Degree.c2d (1.3 MB)


Your’e so brave! XD I’m still firmly in the .010"-.020" onion skin camp


My machine bed is very flat and the piece was large enough I felt that I’d be able to hold it if necessary. The easy going speeds and feeds also helped with my confidence level!


WOW! Both of you guys have perfect edges on those pieces!
@BlindedSands Love the Cube! Perfect fit! I had never heard of a Kawai Tsugite joint before, I would like to make one. And the magnets are a really nice touch. Very well done!

@MikeG Those C’s are so small! Was it hard to get them together? I had to use a rubber mallet on my last section and I broke a piece lol. I don’t see a gap anywhere! Those inside corners look tight!
My bearing setup might be too small for your needs, might have to go up to a larger size. I can give you the bearing housing I used, I just washer them up and leave some clearance for a nice spin. I bore or drill my base hole to 13/64 and tap with a 1/4-20.
1/4 ID bearings
Drill and tap 1/4-20
Fusion 360 link for Bearing Housing

Really nice work guys, very impressive!


Pretty sure that wood is Sapele. Great project!


Thank you @MrHume, good to know! I really like it, very nice wood for machining.

Sapele originates from West Africa, and it can be most easily found in countries such as Tanzania, Nigeria, and Ghana where the individual trees can grow up to impressive height of 45 meters in the air (with some rare examples going up to 60 meters), with the trunk diameter that can almost reach 2 meters (6 feet).

Sapele used for musical instruments

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Thank you for the kind words Max, from a craftsman like you that’s a great compliment!

Let’s say it was a very snug fit. Once the first two pieces were machined I was excited to see if they fit. They did, but it took squeezing a bit from top to bottom to get there. The last piece was the really interesting one as I thought about just gluing it up in case I couldn’t get it back apart. But it did and I was able to take it apart again with a lot of patient squeezing. Actually thinned the glue a little before applying which I’m glad I did! Having the rubber mallet and block ready was key as they were required to get the final few thousandths of alignment.

Thanks for the bearing setup. I was considering using a complicated thrust washer system but yours will make it much easier!


Thought I’d show you all what I ended up doing for the table base, I decided that the prototype I made took too long to cut, and honestly, I didn’t think it looked that great for a table base.

I ended up cutting the two parts for the legs and dominoed them. I just love the precision of designing exactly what I want, cutting on the CNC and simply cleanup and glue!

I made two bases:


Really nice Michael! What kind of lumber did you use on these final pieces?

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That looks really awesome, very cool design, interesting to look at. Love the finish!

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Thanks! The red wood is tigerwood. The other one I can’t find the English name for it. “Louro-canela” is what we call it here.