I´ve always found great passion in anatomy, making stuff and decorating for holidays. In this project I merged all together.
Materials: wood (I used pine), some thermoplast (I used ABS), fishing line, zip ties, glue.
Tools: Jigsaw, scroll saw, rotary tool, heat gun, tweezer.
Step 1: Bones
I started by gluing drawing of hand bones to piece of wood with spray glue. Then I cut individual bones out using jig saw and scroll saw. Later I used rotary tool with drum sander to shape square pieces of wood into more genuine and organic looking "bones". Then I used rotary tool with drill bit to create tunnels for "tendons" and zip ties to go in.
Step 2: Joints
For flexible joints I used offcuts from zip ties. I first drilled slots in bones with rotary tool, then I measured, cut and glued in the zip ties. They provide adequate flexibility and stiffness altogether. This was pretty straight forward except I needed to measure the ties rather thoroughly in order for bones to be equally distanced and also because some bones were drilled all the way through and some holes were "blind".
Step 3: Hand Attachment
I used ABS because it´s thermoplast and therefore it can be shaped using just heat and little bit of pressure. I started by cutting the shape. Then I placed pieces of steel along the bending lines, so only the exact area would be heated. After this I used heat gun on highest setting to heat the plastic. Then I shaped it and let it cool under pressure. After the attachment cooled down I drilled holes for the tendons to go through.
Step 4: Activating the Muscles
I tied the fishing line to the last phalanx (farthest from the palm) and fed it through all the other phalanxes all the way to hand attachment. There I tied the line to a ring for your fingers to go to, made also from zip tie. For these processes the tweezer was really irreplacable, especially if your hand are calloused and insensitive like mine.
This is basically how the real human hand works since finger doesn´t have their own respective muscles and are moved by muscles of palm and forearm.
I always wanted to do something like this and I´m very glad it came out as great. This project was not very hard or time consuming - it took only like two days to accomplish all of it, so you still have time to make it before the Halloween comes :-)
Check out my YouTube channel for other great projects. Thank you and happy Halloween :-)