The frame is made from wood... 3/4" x 3/4" fir for the arms, and 1/4" plywood for the body. It's cheap and sturdy... It will take some pretty serious abuse, and if you break it it's easy to repair. The power system (motors, motor controllers, battery) is pretty standard, and uses easily obtainable parts. The flight controller board is an Ardupilot Mega.
About us: We're Mark Harrison and Andreas Oesterer. We've been flying planes, multicopters, and assorted drones for a couple of years. If you like this instructable, come visit us and see what else we're up to!
Almost all the images here have interesting and laboriously typed "image notes" -- mousing over them gives details about what is being shown. The default view of little pictures don't show the image notes, but you can see them if you embiggen them by clicking on the first image of each set.
tl;dr: click on the first image of each set to see photo commentary.)
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