Warning : This is my first project here at instructables, so I'll apologize if there might be mistakes, typos or other faults. In the end this is a FREE, good for nothing, fun project that intoduces you to basic kinematics with stuff that can be found in any place where there is a shaving guy, some cd/rack with old CD:s and time to burn.
( If the above video doesn't show you can watch it at http://www.youtube.com/watch?v=jTUqKATp2eM )
Step 1: Parts.
What you need for this project if you would like to follow my lead is:
4 BIC razors (minimum)
A scavanged watch. Naturally you'll need some kind of body, and a blastic housing for a watch is the choise for this project.
A small saw. I actually used a lazer-cut bred-knife without problems.
Drills or a hot needle . All the joints are wire-connected which makes it essential with holes roughly the size of the wire. A hot needle (keep it over a flame) will do, but it's messy as the plastic evaporates with ridges and the needle easily gets stucked as it cools. Use a drill if you have one.
Metal wires. A myst for joints. You can actually use tooth-pics or similar as alternatives as long as there are no serious friction or too loose joints (this is the main job; finding that right looseness of joints and yet keep them sturdy). I also used brass-wire (quite flexible) for the connection of the arm-to-leg movement.
A good glue-gun. If you want all the parts to stick this is a must. Super-glue or similar will also do it, but plastic has a tendency to flex and crack the glue-points over time.
A CD, a big CD-case and a felt-pen hat or similar as an axle . The spider is attached to the central column of a CD-spindle (one of those where you have like 50 CD-R records from the store. Through the column I used a wooden flower-pin as an axle. The axle is then attached to the CD which is locked to wheels from a toy-car . The wheels are connected to a lever that you turn to move the whole thing. I also attached an axle under the cd which have two toy-wheels attached to secure the position of the CD-record.
I also used square pearl that I found in my daughers playpen which elimitaded the need for some drilling in the casing, but I don't think they are needed. Yet you'll need some kind of extension between the upper and lower case to created enough space for the mechanics.