# How to cut a Box Joint on an plank



## cybrchef (7 mo ago)

I have a 84” x 14” x 1.5” piece of chestnut oak and want to cut a box joint at one end and use a 36” x 14” x 1.5” as the legs at one end of the future console table.

I have both table saw and router table but can’t figure out how to cut the fingers at the end of the planks.

What’s the best way to cut the fingers for the box joint at the end of the 84” plank?


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## NoNails (Jun 6, 2016)

I will assume with a 1.5" thk the fingers will be app 1" wide. I would layout the spacing and cut say 70% of the depth of cut on the table saw (I am more proficient on the saw vs router table) and finish the cut depth remaining cut radius by hand with my dovetail saw and clean up the finger bases with chisel as I would when cutting dovetails.


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## ChefPhish843 (7 mo ago)

I would use a hand router. Bring the tool to the work piece


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## Woodworking Wolf (Sep 17, 2021)

I did something similar years ago, but the boards were only 12" wide and 3/4" thick. I had seen jigs built for a table saw that would supposedly do the job, but I couldn't see trying to stand up an 8' board and running it through my table saw.

I had a dovetail jig that could cut box joints. I used the jig normally for the 36" legs, I just had to put the jig on a table that was tall enough for the board to clear the floor (the board you cut the fingers in is mounted vertically in the jig). For the longer board (84" in your case), I mounted the jig on the end of my bench 90 degrees from its normal position. That allowed the long board to be in the horizontal position, laying across my bench, so length was not a problem. It took a bit of work and thinking but turned out well. I realize you might not have a dovetail jig or if you do it might not handle boards your size. Plus, it would be a big cut for a router (assuming sizes @NoNails mentioned) and thus take multiple passes.

Check out this old thread. I find post #24 interesting and something I would try provided I wouldn't be bothered by the open cuts on the inside of the corner. You could always cover the cuts on the inside, maybe with a triangular piece, maybe including it as a design element. A plus would be that this piece might add some strength to the corner.








How should I cut this box joint?


I'm getting ready to start on a 4'x2' chest that I'd like to use a box joint for the corners. I have done a few box joints, all on a jig for the table saw, but they were on much shorter pieces that 2', let alone 4'. I'm not sure how hard it will be to cut box joints in a 4'x 2' panel on a table...




www.woodworkingtalk.com


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## FrankC (Aug 24, 2012)

If the back is not visible you can use a 8" dado head raised full height with the plank horizontal on your table saw as explained in post #24 in the above link.


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## woodnthings (Jan 24, 2009)

edited

See post 19 for the explanation and photos.


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## difalkner (Nov 27, 2011)

woodnthings said:


> There are only 20 posts in the link above.


There's a second page; there are 24 posts.


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## Woodworking Wolf (Sep 17, 2021)

difalkner said:


> There's a second page; there are 24 posts.


Yes.

While I referenced my liking of the way described in post #24, I gave the link to the first page so that the OP on this thread could see the different suggestions for how to do what he asked about.


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## Half Fast Eddie (Jan 12, 2022)

ChefPhish843 said:


> I would use a hand router. Bring the tool to the work piece


And square up the fingers with a sharp chisel.


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## GeorgeC (Jul 30, 2008)

ChefPhish843 said:


> I would use a hand router. Bring the tool to the work piece


Agree. A piece of oak that large will be heavy to maneuver.

gmc


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## B Coll (Nov 2, 2019)

cybrchef said:


> I have a 84” x 14” x 1.5” piece of chestnut oak and want to cut a box joint at one end and use a 36” x 14” x 1.5” as the legs at one end of the future console table.
> 
> I have both table saw and router table but can’t figure out how to cut the fingers at the end of the planks.
> 
> What’s the best way to cut the fingers for the box joint at the end of the 84” plank?


I would approach it like dovetails. I would do the leg first and transfer it onto your 84" top. Draw your cut lines with a marking knife. I would hog out the majority with a router being careful not to get too close to the cut lines. If you do not have them already I would make some fixtures, square blocks, to clamp to the surface and keep your chisel on the line, and square (plum). Creep up on a perfect fit. Remember, you can not put the wood back. Keep your chisels wicked shaaarp.


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## DrRobert (Apr 27, 2015)

My thinking is along the same lines as BColl^, except routing that thick of much material incrementally will be a chore.

Cutting on the waste side, I would drill out the bottom and saw the sides out with a handsaw, use either a router ans template or paring block to clean up to knife line. If he doesn’t have a chisel or those skills a router template is the best route 😁


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## Bob Bengal (Jan 2, 2021)

cybrchef said:


> I have a 84” x 14” x 1.5” piece of chestnut oak and want to cut a box joint at one end and use a 36” x 14” x 1.5” as the legs at one end of the future console table.











Finger Joint Jig


But this jig will make variably-spaced finger joints and ensure that both halves of the joint fit together perfectly. The simple design creates a hassle-free setup for perfectly sized and aligned joints. The keys on top of the jig are sized to match the fingers of the joint, ensuring a perfect...




www.woodsmithplans.com





This jig is shown with both the work piece and router vertical, but horizontal is possible too.


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