There are a lot of ways to make box joints, so I won’t recap all the different tools/jigs possible, rather just go over what I used.

I use a «box joint cutter set«, which is a fancy way to say a reversible, two blade dado stack. Depending on whether you put blade A on the left or right will determine whether the dado is 1/4″ or 3/8».

To match the thickness of the stock, I went with the 3/8″ configuration.

I use Incra’s IBox as my jig. While the Incra’s I-Box is pricey, and it isn’t the fastest jig on the market (it is difficult to do gang cuts with it), the micro-adjustability and repeatability make it a great choice for small boxes. It works on both a router table and table saws (using a dado stack). If you do have an ibox, I high recommend watching Incra’s setup tutorial on it — it is a very dry, but effective learning tool.

I have my jig dialled in so that it cuts a box joint with a 0.02mm/0.0007″ narrower finger than the spacing. You may not want the finger and spacing to be perfectly exact otherwise they can get very difficult to assemble and run the risk of cracking/splitting during assembly.

Ideally, you want the box joints to be a hair proud of the material — 1mm/1/16th or so over — its better to have to clean up that material later than it is to have gaps or joints that are sunken.

Remember: Test on scrap wood, lest you scrap your project.

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