This is just a guide on how I go about making moveable hands for my stop-motion character. I thought I'd post it up in the hope that it could help other people out.
First of all you're going to need a mould, so see my other guide on how to make one if need be.
Next, get some super sculpey/plasticine in one halfof that mould, whatever colour you'd like your hand to end up. Be sure to really wedge it in there, get all the gaps nice and tight.
Now, on top of this layer you've built up, lay the soft wire 'bones' of the hand that will allow it to be a bit stronger and hold its shape. You can see two types I use here, the simple hoop usually suffices if you're using a medium that holds together quite well, but you may want to go for the individual finger bones if you want something that's going to last a little longer. Just make sure the wire you're using is nice and soft! Push them down below the surface of the scupley.
Next, lay down some more sculpey on top of the 'bones', making sure to cover it all, don't worry too much about neatness at this stage, just making sure that the 'bones' are well covered, with excess sculpey if need be. It's better to do too much than too little here. Then place the other half of the mould on top, and squeese firmly (but don't break the mould).
Carefully open up that bad boy, and marvel at the little hand you've created. You may need to trim away and excess 'squeesed out bits' around the edge.
Next, using the strongest point of the arm, carefully peel out your hand. Then its just a case of trimming the wrist off, to expose the 'bone' and smoothing out any rough spots.
And there you have it, a hand ready to fasten directly onto the character, and easily replaceable as it deteriorates!