A Curious Contraption


For the past few months, we have been collaborating with the lovely Sarah Alexander of Cabaret Mechanical Theater, scheming up all sorts of playful ways for people to engage with the amazing world of automata (including an automata idea generator twitterbot, inspired by Paul Spooner's machine for computing the names of 13,500 ventriloquist dummies). 

Paul Spooner's excellent automata machine 

Paul Spooner's excellent automata machine 

Cabaret Mechanical Theater has a traveling show called Curious Contraptions that is making it's way around the US right now, and Sarah asked us to dream up a sign that could go along with it. I knew I wanted to make something mechanical, and Cabaret has written an excellent guide to making things move, called Cabaret Mechanical Movement, so that seemed like a good place to start. Automata use all sorts of interesting cams to get different motions, and I thought the sign could be a good place to showcase some of them and encourage visitors to look for them throughout the show. 


I came up with a rough design, where each letter in the word CURIOUS has a different type of cam to make it move in an interesting way, except for the I. For that letter, I decided to try making pin gears (luckily there are some helpful hints in the Cabaret Mechanical Movement book!) Paul Spooner and Matt Smith often use pin gears in their automata, and they are just super cool. Paul and Matt, that is : )

pingear test.jpg

So far so good . . . the next step was making a "cam kebob" with different types of cams, to see if I could make the whole word move. 

cam kebob2.jpg

I used threaded rod and nuts to hold the cams in place, so that everything would be adjustable (very helpful when you are tinkering with something new!)The next step was clamping together a rough frame for the sign, and cutting out the letters on a scroll saw. Who needs a fancy laser cutter! (we do. we really, really do)

cam kebob.jpg

It worked, but I could tell that powering the whole sign with a little motor and pin gears was asking for trouble, so I decided to go for a bigger, slower gear motor, and to try making some wooden gears. There is an awesome resource for this, an online gear generator that lets you design your own gears and download an svg that you can cut out on your laser cutter (or print out on copy paper, glue to a piece of plywood and cut out on a scroll saw) 

That seemed to work, so I added another gear and another cam kebob to animate CONTRAPTIONS, and tested it out . . .

And discovered that my plan to move CONTRAPTIONS was not going to work! I had made a kebob of eccentric cams, and thought each one could lift a lever with a letter attached to it. Turned out it was way too much weight, and the whole thing stopped working. So, time for a redesign.

Now the cams were pushing the letters out, instead of trying to lift them up, and it worked beautifully. Whew!

Next challenge, we realized that having the wooden gears exposed could be a pinch hazard (and who can resist touching things? I know I would be tempted). I switched the design around to place the gears on the inside of the box, still visible, but out of reach. 

Hopefully this sign will be a nice invitation to the Curious Contraptions show, inspiring visitors to look closer, and to make their own curious contraptions in the cardboard automata workshop. 

I just packed the sign into a crate, and it's on it's way to Albuquerque right now. If you are in the area, go see the show at Explora! It opens February 17th, and runs until May 20th, and the automata are amazing. 

keep dry stencil.jpg
Nicole Catrett