Week 8 :CNC Machining

What?: Re-configurable architectural site model.

Software: Rhino 4.0, MasterCam

Tools: Techno CNC, Router (for sanding off tabs), jigsaw, sandpaper.

Materials: 8'x4' MDF board, 3/18" treaded rods, wing nuts



1. From Rhino to MasterCam: The first step is to set up my site model file and turn it into profiles from a 3d mesh. I accomplished this by first turning the mesh into nurb surfaces and then using the contour command in order to cut the surface at the given intervals (in this case the thickness of the mdf).

In order to turn your file from Rhino to MasterCam it is very important that you separate the different elements you have into different layers, for example, in order to drill the holes for the threaded rods I located a series of points, so I set up one layer that exclusively contained the points. This will make it easier to set up your different tool paths and different bit sizes once you get into MasterCam.


2. MasterCam, Milling: After separating your different components in Rhino you can import the Rhino file directly into MasterCam, I set up a couple of different toolpaths, one for each type of cut I need: Lines and Points.

It is also key to remember to put tabs on whatever you are cutting, this is important because without the tabs your parts will move around as you are cutting them and this is not only dangerous as they might fly and hit you but it will also result in damage to your parts..

Sidenote: I have heard from some fellow students that MasterCam is much more complicated than other software packages such as Visual Mill, so if you are inclined for this option here is a very useful tutorial that will take you through the steps for creating your cnc milling file.


3. Post Milling process: After the CNC has done its job, I had to cut the tabs so that my parts would fall off, I found that the best way to do this was with a jigsaw, it is also important to know that while the edges looked really dirty once the pieces were cut it was very easy and quick to clean them up with a router and some sandpaper, the router takes care of whatever remains of the tabs and the sandpaper clears all the fuzz in the edges of the piece.


4. Assembly: Since all the holes for the threaded rod and the connections were laid out on the Rhino file everything fit exactly as expected, it was really easy to put the tread and the wing nuts. I expect to make changes to my project later in the semester so my site will also change which is why I used wing nuts, they will make it easier for me to take pieces in / out and reuse the model.


4. Final product: An architectural site model that is easily transformed as your project changes thoroughout the semester, making it wasy to always have an updated presentation standard site model.

Replaceable parts..