Laser Cutting and Assembly

A project log for Bi-Copter V2

The objective of this project is to design a frame for an RC Bi-Copter in CAD with laser cutting in mind

SpencerSpencer 11/18/2016 at 22:010 Comments

I made the design to be laser cut and after finally getting the chance to use the laser cutter at my university it came out perfect! A big thank you to the staff member that let me make use of it.

As you can see there are a lot of parts. The parts did take a while to cut but it would have been hell to do this many small parts on my cnc. I'm really happy with how it turned out. They fit together perfectly and the frame feels strong. I started building it but I'm short one servo. I had three servo's but turns out only one of them is in great condition. Ones okay and the other totally busted even after a gear change.

Designing the motor buckets was a challenge but I think it turned out very well. The left side bolts to a servo horn with 2mm bolts. The right side is the free spinning side. I used a 1/4 inch side plate and 2 0.25 inch spacers also cut from the same sheet. I ran a 1/8 inch brass rod down the center and glued it all together. I trimmed the rod off after the epoxy cured. There is a bit of wobble in the joint. There might be better ways but this should be good enough.

The final motor mount came out quite well. The pivot action is smooth even with a little bit of wobble on the free joint. I put the motor on top of 4mm spacers to get the center of gravity just right. I want the COG to be right at the pivot point. My previous design had the pivot well bellow the COG and the off center torque was bad enough to snap the gears in mid flight. The whole assembly clamps onto a 10mm carbon fiber spare that insets into the left side.

As you can see the frame is mostly complete. I'm just waiting for a servo then I can finish it. I really like the current look but I do regret not painting it. Maybe I'll still do it but I really don't want to have to take EVERY thing apart. Hopefully my next update will be of it flying.

I'm thinking of uploading the files under Non-Profit Open Software License 3.0 (NPOSL-3.0).