Morris Dovey’s Bevel Platform for CNC Tenon Routing
I built this plywood fixture because I wanted to hold boards at an angle while I routed angled tenons.
Side view - the protractor scale was routed using a 1/32" end mill. Each of the marks was cut with four 1/32" passes for a total depth of cut of 1/8". Each tick mark is one degree...
...and between the one-degree tick marks I peck drilled a hole to mark half-degrees. In actual use I do the setup with a digital protractor that is accurate to a tenth of a degree.
Here's the jig mounted on the ShopBot - set up and ready to rout an angled tenon on the end of a 1/4" x 3" rock maple board.
This close-up shows how I use a piece of 3/4" baltic birch plywood with a small piece of scrap (of the same thickness as my workpiece) to clamp the work in place while routing.
This should give you an idea of the need for accuracy in setting up. The photo doesn't show it very well; but the stock being cut and the 3-flute end mill are both 1/4".
Here's a look at the first batch of just-cut tenons. The top piece is the (flipped) first test cut in scrap material.
And this is the first "dry-fit" test of the joint.