Lockable Ball & Socket Pivot Joint For Helping Hands

One thing I really want to be able to do with the maker bot is make more things to help me make more things.

This is an experimental design for a lockable pivot joint intended to be used (with about 5 brothers) in making a set of helping hands to hold circuit boards etc.

This should print without any problems on a makerbot (although it's small at the bottom so may be a little unstable - need to watch that :)

The sections join onto each other and the nut can be used to tighten the joint or lock it in a fixed position.

This could also be used to create pose-able armatures.

The full design for the helping hands is not ready (I've not finished modeling the clamp grips (variations of the same mechanical principle).

This is my first attempt at a screw/bolt thread, if anyone tries to print this out please let me know how it goes, I try very hard to respond to feedback in my designs and I'm happy to take suggestions.

UPDATE:
An updated version of this part can be found in my helping hands design: http://www.thingiverse.com/thing:2972