I've built a couple of KAP related templates and put them up on thingiverse.
The first was a picavet for the rubber band and pop bottle rig designed by the smart folks at www.publiclabory.org. http://www.thingiverse.com/thing:29308
. To be honest, I haven't used it with a camera after building my first autokap rig. I have been using it with a liter of water as a dummy load.
Recently I've been playing with a light weight camera rig. I've used different plywood, from 2.5 to 5 mmm. I intended to use carbon fiber for the struts, but I find aluminum so much less involved to work with that I may not get around to it. Here's a picture of the most recent prototype.
. Currently around 430 grams as an arduino AutoKap. There's some obvious fine tuning to be done. http://www.thingiverse.com/thing:34200
Thin wood works fine if you orient the grain & avoid side blows. I broke several picavet arms when a pop bottle rig tipped and dragged. For the current rig I ended up doubling the side supports, but I'd love to find some 5 or 6 ply in 3mm and see if that was enough.