Just an update on my 3D printed quad project. I have just published my quadcopter v2 to Thingiverse.com. I've flown my first 3D printed quad for over a 100 hours and although it worked really well there were nagging issues with the design that needed to be addressed.
The biggest issues were with the arms. The legs, although lightweight, proved to be very brittle. I must have superglued the legs back on 10-15 times. So I went ahead and beefed them up a bit. The are now wider and have extra support added in weaker areas. They are still very light and although they could still break off they are MUCH more forgiving of a brisk landing or lateral loading. I also got tired of taking the whole quad apart if I wanted to get between the top and bottom plate to work on something so I designed the new arms to have M3 lock nuts press fit into them. This makes it similar to a dji arm where you can remove just the top or bottom plate without having the arms fall off. Lastly I have added mounting patterns for motors with a triangular pattern as well as the more standard 16x19mm.
Because I have been flying with the APM now for a while and thoroughly enjoy it I thought I had better design v2 around it. The new top plate has 50mm mounting holes for standard flight controllers like the kk2.1 and kk blackboard. They can be mounted orthogonally (kk2.1) or at a 45 deg angle (blackboard). The APM however mounts with vibration dampening bushings from hobby king. I stuffed earplugs inside to make them a little more rigid and the results were good. When vibrations were measured, without any prop balancing, the vibrations were half of the limits that 3DR prescribes. Extra holes have been added to help with weight and make it easier to route wires and the top plate has an added area for the APM's GPS/Compass module.
I slightly retouched the gimbal as well. I added a GoPro 3 case on top of making the gimbal arms easier to assemble, again using M3 locknuts.
All in all it is very similar to my original design but I feel that that one was the test bed and this one has a much more professional feel to it. I hope to see more of them printed and flying. I can't say how much I have enjoyed designing this and bouncing ideas off other people who have printed and are flying it.