Clamping workpieces vertically for perfect finger joinery and Y axis overhang

I know that you can’t cut square corners with a round bit and I really don’t care for the way dogbones look.

I just got my S03 XXL and haven’t built it yet (have to finish a honey do project then build a torsion table for the machine) but as I am working on designing my table, I am trying to think about the best solution for holding work vertically so that I can mill the end for perfect finger joints. I have been poring over the forums, youtube, and googling to see what others have done and I have come across some interesting solutions.

However I am trying to get a clear picture on a few things before I go too far down the road on a design.

I understand that the Shapeoko has some amount of Y axis overhang off the front of the machine which might be usable. The idea is that I will have a pair of T tracks on the front vertical face of my table end, I could clamp work in a vertical orientation and use that overhang to cut fingers.

How much usable Y overhang off the front of the machine is there?

55.5625 mm

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Interesting idea,I would suggest that you have this front facing support removable for a few reasons:

Unless you are planning on making joints all the time, t will be in the way or at least restricting access during normal operations;
You may need to move the machine for servicing so it could become an issue if it is attached vertically to your tracks;
You may want access from the front to put things under your table/enclosure and the tracks may be in the way.

One thing you may want to consider is tiling. You may want to have a trap door at the back of the enclosure to have a work piece extend behind. Tiling makes it possible to mill pieces larger than your bed by sliding them on the work surface.

You may also want an access door on the left side to access your controller without moving the Shapeoko. Other things to consider are dust collection (the noisiest part of operation) and you need to get the vacuum tube in without impeding movement, ventilation, lighting, access to the components for servicing and cleaning. If you ever want to upgrade to HDZ,you would also need to consider the height above the gantry.

My Shapeoko sits on a temporary torsion box and making a proper enclosure is on my to do list too and I’m looking forward to seeing how you make yours with the front T Tracks as I have many ideas but I have not finalized my design.

I hope this helps.

I published a design:



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Thanks @neilferreri!

This helps describe how much space I have to work with. 2 inches should be more than enough for my application.

@luc.onthego, Here’s what I am toying with.

I just used some random clamps in the model from the sketchup 3d model library.
The basic idea being that I can clamp to the front, with the rails recessed into the hardwood edging that I intend to use on the table. This is just a mock up. The top skins on the torsion box will not extend to the edge of the table.

Right now its 3/8s mdf for the internal structure of the table with 1/2" or 3/4" MDF skins and 3/4" hardwood edging on the outside to improve durability.

I am going to check out a local plywood supplier this week and may adjust my designed based on what they have available.


Please note that the overhang varies depending on which router mount you use and where you measure from.

I think it’s more like ~35mm on most machines (half the router diameter) and note that you really should measure to the center of the endmill.

I’ve gone in and edited the value to make it more pessimistic (which I’d thought I’d already done)

I am curious on these and I am playing with some designs myself: Do you typically use some kind of sacrificial backing board with this? If not, do you see a lot of tear out?

Used a #251 downcut bit, and left a roughing clearance and took a finishing pass — nicely crisp joints which fit perfectly (if a bit proud — need to add a surfacing pass of the board ends).

Interesting how you have this designed but I have a couple of concerns you may want to take into account.

I am wondering if you clamp only at the top, will the momentum of a long piece make it difficult to keep it properly perpendicular? The clamping is system is attached to the torsion box, not the shapeoko frame so any movement of the Shapeoko on the torsion box would mess up the alignment. It would not take much misalignment to mess up the joinery.

I can’t resist sharing what my friend designed and built.
Perry built this for one of the Shapeoko in the shop.
The video was used at one of SDFWA’s general meetings in San Diego.


Thanks for sharing this @TravisGood Do you have any more details other than the video? I can see whats going on here but just wondering if the spindle mount has been modified at all and what all is going on there. I found the JointCAM website and there are a few posts on the forums about jigs but nothing to the degree of finish as the one in the video.

This is pretty much exactly what I was thinking of but couldn’t find any real good examples of it so I was going through a little bit of development as a result.

I like how it cuts both sides of the joint in one pass…very clever.

To the points that @luc.onthego mentioned, I had considered the clamping apron. I will likely end up with something similar to what @TravisGood shared with a longer apron with t track down the front.

Also I fully intend to anchor the shapeoko to the table so that it cannot slide around. As I learned with my 3d printer, stability and rigidity go a long way towards accuracy. It goes for a lot of things actually. If you put more weight on a telescope than it is designed to carry then your accuracy will suffer as the mount struggles to maintain tracking.

So far thanks to everyone who has chimed in. I have a lot to think about

I built a fixture to allow vertical joinery on the SO3 as I’m not a fan of the mickey mouse ears joints that are common to horizontal joinery. I originally built it for JointCAM which is a very good software tool that helped me get started. I’ll continue to use JC along with other custom joints. Once you get started with vertical you will realize that the possibilities are endless.

Btw, the major challenge with the fixture was securing a tight fit on a platform that could not stick out beyond the front of the SO3 very far and use up the extra Y. If I were to do it again I might have considered using thinner alum. Also is the rigidity of the platform where we tapped 1/4-20 holes in the front of the SO3 and also the table that it was sitting on. That thing was not going anywhere. Here are some pics detailing the design and some interesting cuts inspired by Mirock.FixturePic SDFWASmall



Thanks for sharing the design. Is the front apron removable? One would have to consider the ability of using the apron in the design of an enclosure.

I looked at the joint CAM and it is interesting if a bit expensive for the amount of joinery I need to do.

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@pcrutchfield Thank you so much for sharing these details.

This is very similar to what I was thinking about for my machine and while my drawing doesn’t show it, I was already considering a clamping apron down the front of the machine.

Not sure what you mean here. is there an aluminum plate between the vertical clamp board and the table/shapeoko?

Are you saying that you drilled and tapped the front frame to accept the large knurled nuts? It looks like there are 4 holes in the front frame, 2 on the bench edge, and two more that connect the vertical end supports of the clamp board through the bed of the vertical clamp board and into the frame of the bench. Also is the machine itself bolted to the table?

Would you be willing to share the CAD file? I’m curious about some of the construction. As I work through the design of my table I am going to plan for this kind of jig as future upgrade and if I make some design decisions now, it will make retrofitting the clamping apron on the front easier.

It is removable but not easily via the 8 knobs.

Since we are looking for the most possible Y clearance in front of the machine using .25 aluminum for the material mounting base (the apron) instead of .75 baltic birch ply would give you .5 inch more. You would have to think of another way to mount the t track.

Yes we tapped the front frame of the SO3. The fixture is bolted to the S03 and the table effectively bolting it to the table.

I’ll send you a STEP file that will keep you busy for a while…


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Clearance is why my design places the stock directly against the front endplate.


I finally got my take on doing finger joints finished and I wanted to add it here.


Great video, I watched it last week, I will try to adapt your concept to my new Shapeoko bench and enclosure. I also want to make the jig a bit wider for making larger boxes