The clevis: http://www.thingiverse.com/thing:5889 needs a mate.This thing, combined with a female clevis, will form a joint. Depending on what you attach the inserted bars to, very interesting degrees of freedom will ensue.This thing has a M3 hole in the position where a matching clevis can be joined. You can use an M3 bolt/nut combo, or make the hole any size you like and use more exotic fasteners.the most ideal situation would be to put tiny little ball bearings in there, and a nice precision pin as a joiner. But, using a simple 3mm piece of ABS filament will also do the trick and if you melt the end a bit, provide you with a quick fastener.1) Excitedly look at your design for places where you can use a clevis joint 2) Print this thing, and the clevis female thing. 3) Line up the holes, and put a piece of ABS 3mm plastic in there. or Use whatever fastener you like. Whatever your choice, it needs to be able to pivot around the hole, and it needs to hold the two pieces together. 4) Secure a shaft into the larger hole with glue, or whatever suits your material 5) Rejoice!