Dogbone fusion 360 plugin

Outside corners can be sharp, inside corners must be rounded. Since a round end mill is doing the cutting, the radius of any inside corner will always match the radius of the end mill. Sharp outside corners are easy, but there's no way to get sharp inside corners with an end mill on a 3-Axis CNC.

Dogbone fillet

This corner treatment allows for a flush connection between the parts because the end mill travels outside the corner at an angle so that the cut is made equally on each leg of the cutout.

This plugin makes that operation easy : https://github.com/caseycrogers/Dogbone Follow the instructions to install it.

Here is an explanation on how to use it : http://youtu.be/EM13Dz4Mqnc