When I lent my services to a collegue who was working on a film about 12 years ago, I was introduced to the world of cnc. I remember watching this huge machining centre milling out a slab of mdf and turning it into a fantastic set of gears. I knew that it would have taken me hours to achieve the same thing with traditional power tools. I decided then that I would invest in a cnc router for my own business Oxenham Design. At that time I could turn on a computer, but even to check email seemed like a crazy set of operations. I persevered and learned every piece of relevant software I could get my hands on. I am now fortunate enough to be using Vectric's ASPIRE software, and Techno cnc routers, which has helped us to create some amazing projects, both in part, or in full. I thought that this blog would be a great place to share "behind the scenes" adventures with the software, materials and equipment we use, as well as the projects we build.

Tuesday, 8 March 2011

After bringing in the face portion, and this is where Aspire shines, I was able to slice the model into 3" thick components. We chose 3" styrofoam for 3 reasons. 1 was our under gantry clearance 2 was our cutting tools flute length. I wanted the cutter to be able to cut the material in 1 pass. And 3 was that styrofoam is LIGHT! After moving the components around to maximize our sheet space, I defined where I wanted the cutting borders to be. I obviously didn't want the router to waste time by cutting the flat portions of the top of the material sheet.This was very easily done by selecting a component in the 2d window and selecting the "fit vectors to bitmap" feature. This let me define the top of the sheet and automatically create a boundary vector. I also put a border around the base of the component as well. With our 3 day deadline, these features are indispensable!
 The next step was to apply a toolpath that our router would use to machine the parts. I used a 1/2" ball nose cutter to reduce machining times as the model was definitely large enough that it would still have lots of detail. After running a simulation, I could see that the eyes didn't have the detail I wanted. Easy enough. I drew a vector bounday around each eye and applied a 1/8" cutter tool path to just that area. The final step was a cut out pass.

I have gotten far more efficient with my toolpaths over the years. I purposely stayed away from all the vertical edges of the model by limiting the tool to not going all the way over the edge. All of the vertical edges would be undercuts anyway, so it is way faster to do it this way and just do a final cutout. We still have to do SOME manual labour!  

1 comment: