After building a couple of 3D printers and a CNC router, I found that many of my friends would quite reasonably inquire as to what I actually make using these machines. For a long time my reply was that I used them mostly to make 3D printer and CNC router parts, after a while allowing me to come to the realization that my obsession with these machines was, quite literally, feeding itself.
All that changes with my latest project: to build a heavy-lifting, full-featured aerial hexacopter drone with as many parts as possible being CNC routed or 3D printed in-house.
The first thing that I had to settle on was what design to use. I had been following the progress of many projects at DIY Drones. One of their very active participants, Jeremy Guillory, published this blog post describing cutting a bunch of hexacopter frame parts out of Lexan (polycarbonate) using a water jet. He also supplied the CAD DXF file that I could use to make those same parts with my CNC router.
The next step was to figure out what material to use. People have been building multi-rotors out of almost every light/strong material imaginable. At the Holy Grail high end is of course, carbon fiber. But the cost is very high and if I mess up a cut, I waste a lot of money. I could have also done it in fiberglass or Aluminum. In the end, I was persuaded by a fellow I met at this year's NYC Makerfaire that I should use a material called Dibond. Dibond is a composite material consisting of a polymer sandwiched between two super-thin sheets of Aluminum. It is light, yet strong and rigid. It also has some helpful vibration dampening qualities. Best of all, it happens to be inexpensive. I bought 5 1/8" Dibond sheets for about $10 each, shipping included. Cutting all the parts required 1 and a half. I had to kill the job at one point when an inadequately-secured part got sucked-in by the bit but I was able to zero out the CNC machine and continue.
The Aluminum arms can be acquired quite inexpensively from HobbyKing.com ($0.88 each!).
My goal, beyond documenting this build is to leave my fellow makers with instructions to build their own full-featured aerial robot at the lowest possible cost.
Stay tuned for more shortly.