This instructable will show you how to add a moving jaw to a skull, pumpkin or other holiday prop. I used this one to make my 3 Axis Skull on my Cauldron Creep talk when a motion detector went off. This circuit does not require any programming to sync up with and audio source, but I will include some arduino code to control an MP3 player for taking it further, as well as show you how to add a trigger sound to an audio file if the source audio has lots of ambient noise preventing the circuit from detecting the correct time to open and close.

Here is an early jaw test using a Charile Essers youtube video as the audio source. No editing of the original sound was made.

In most of the videos I've included you'll see either the skull moving in 3 axes with a NOD, TILT, and ROLL, or it performing a regular Cauldron Creep motion (as designed by Devils Chariot). This instructable will focus mainly on the jaw motion. I will eventually post instructables on each of the different parts but wanted to focus on each mechanism individually.

If you just can't wait for that massive set of instructions, and want to tackle that HUGE time consuming project, here are links to essentially everything else you will need:

3 Axis Skull Options:

1) Triaxial Skull Labs (I based my self build off of this design, which Don shared in another forum, but used a modified socket universal joint instead of a spring. Condolences for your loss, you will be missed)

I am loath to give out the instructions without Don's permission. The gist of it can be gleaned from these handy assembly videos on youtube, or are available HERE if you are a member of the garage of evil Halloween forum.

2) Halloween Bob's Designs

3) Skulltronix

4) DIY, here's a video of the mechanism in my skull



Cauldron Creep:

1) Devils Chariot

2) Scare FX stirring witch

DIY Cauldron:

1) I followed these steps.

I've also included tidbits, code, and other useful stuff on all of the above in the remaining steps here.

** As you can see I tend to include a storm of links in my instructables, you've been forewarned... ONWARD!!!!