CNC Finger Joint Box

One of the notable features of the Shapeoko is that it has the working area projecting past the front of the machine (~1 1/2"). This allows one to cut large or oddly shaped objects within that projection --- one intended use for that is clamping boards on end to the front of the machine and cutting joints into them. There are a number of possible joints which may be so cut (see Joinery).

Discussion of this at: http://community.carbide3d.com/t/cnc-finger-joint-box/8880 (which at this time, has a more complete discussion than this unfortunately incompleat page)

Also see: https://community.carbide3d.com/t/design-into-3d-boxes-magazine-storage/16238 which systematically works through the design considerations.

See: https://cutrocket.com/p/5cb25f3380844/ for a fixture design

Any box design starts with the dimensions, for this example we will use:

6 in wide 3 in long 4 in high.

Finger joints are determined by:


 * the size of the endmill which one uses (1/4" for this example)
 * the thickness of the material (we will use typical nominal thickness 1/2" craft boards, actual thickness: 0.375")
 * the spacing and number of the joints / pins
 * additional material removed for the glue line

and the box itself will be determined by how the top and bottom are applied. In this instance we will cut grooves on the interior for 1/8" plywood.



Essentially all one needs to do is do the math to determine what length the boards need to be cut to, and where any grooves need to be positioned for a lid and/or bottom, and then work out the spacing for cutting the joints into the ends --- this is easiest if one can mount all four boards at the same time, otherwise, the two boards for a given corner should be positioned to be cut at the same time, positioned in a fashion which will match the assembly orientation.