Design

Designing for CNC

The main lesson I learned from this project was to design with the tool in mind. I had to make sure the bits could cut between the walls of the case and standoffs. I ended up increasing the overall dimensions of the case to accommodate for the 1/8" flat end mill. 

Acrylic Face Plate

For the face plate, I wanted to make wall to prevent the plate from falling into the case. I wasn't able to do this because the tool would intersect with the standoffs. Increasing the width the case wasn't a feasible option because that would make it hard to connect cables. So instead, I went with a simple recessed base that would hold in place with friction

Friction Fittings

To hold the two halves together, I added an inner lip along the edge of the top half of the case. I made sure to add a small offset (0.1mm) so there was a little bit of clearance to allow the two halves to fit together. I couldn't create certain geometry in the corners of the opening for the acrylic face plate because the 1/8" tool can't cut geometry with a smaller radius then the tool itself. So I ended up adding a chamfer to those edges.

Skinny Fingers

These fit in between the USB and Ethernet ports. I normally wouldn't make this, especially for 3D prints because they tend to be too thin and break easily. But with CNC milling, these areas can be cut just fine. I used a 3D pocket operation. Although I wasn't able to create sharp corners, the offset was enough to fit in between the ports.

Download Source and STLs

If you're interested in checking out the design source, I made the Fusion 360 archive a public download. You can also grab the STLs if you'd like to try 3D printing the parts – However, I don't know if the tolerance will be the same.

This guide was first published on May 03, 2017. It was last updated on May 03, 2017. This page (Design) was last updated on Nov 17, 2019.