Rotary Cut Radius Box Corners

You can cut a rounded corner for a box as a two sided job on your CNC as shown in a previous post:  HERE

You can also cut the rounded corner on the rotary axis of your CNC from the same rectangular starting block. 

16" Long 90 Degree Rounded Corner

What the CNC thinks it is cutting

Actual ends shown in the first image

The centers on the block ends must be a little lower than actual when mounting the block on the radial axis. The profile shape must be placed so all parts of the inner curve can be reached by the bit as it rotates around the center. Very little material is taken off the rectangular block compared to what would need to be removed from a cylinder of wood for the same result. No roughing pass is needed given the small stepover taken by the bit when cutting this shape from a block. For this example I used a 1/4" diameter ball nosed bit. 

Vectors Used

The starting block for a rounded corner with a 1" internal radius and 1.75" external radius is 2.5" wide and 1.0625" thick. Adjust the starting block size to encompass different sizes of rounded corners.  I recommend making the block 2" longer than the final part you need to keep the router/spindle chuck away from the rotary axis chuck and tailstock. 

An example Aspire CRV3D file for this specific project can be found on Vectric's forum here:  Forum.Vectric.com

The actual vector used for the final cut was created with the "Unwraps selected Object" tool you can only access while in a rotary job. 

I helped students with rounded corners for their cabinet projects several times over my teaching career. This is one creative application for the rotary axis of the CNC. 

Question, critiques, and comments are as always encouraged.

4D