Mechanical Foamcore Models

I’ve been asked a lot about how to get started building mechanical contraptions and I always mention Keisuke Saka’s excellent book Karakuri, how to make mechanical paper models that move. The book has actual printed template pages that are meant to be torn out and used as building materials. The first time I encountered this book it was on loan from a friend that had built most of the models already, so I set out to replicate the basic mechanisms using materials that I was comfortable with, and that were quick and easy. Foam core, paper clips, skewers, paper, and plastic bits from yogurt containers.

I like this approach because paper craft can be intimidating for new makers as it requires patience an precision, and when it comes to working mechanical models it is sometimes easier to take a more forgiving approach.

These pieces are not new work. They were the precursors to the one month of small machines project so I wanted to document them even though they aren’t pretty. Page 6 of the books offers a summary of the basic mechanisms:

Most of the models are built on a foam core base that is roughly 2.75″ x 2.75″ by 2″. And for the completists out there, I didn’t build a Crank B.

Cam A – The rod makes a repetitious vertical motion
Cam B – Two rods make a vertical movement alternately.
Cam C – The rod makes a repetitious horizontal movement.
Cam D – The rod slides repeatedly in a linear motion.
Crank A – The rod sways repeatedly in a circular motion.
Crank C – The turning of the crank is converted into vertical motion.
Gear A – The gear turns horizontally to the handle.
Gear B – the gear turns perpendicularly to the handle.
Geneva Stop – A wheel makes turns in a discontinuous rhythm.

For making the gears I used I printed them on paper, glued on the foam core and then cut by hand. The Gear B needs some beveling to make it work.

This is a really good set of mechanisms to get started. Each mechanism will have a set of problems to solve, and solving these problems in whatever material you choose will translate to other materials. I like foam core and hot glue, but you might choose cardboard or wood. Good luck with your builds!

Also if you want an easy way to share these, grab them from my giphy channel here: Cam A, Cam B, Cam C, Cam D, Crank A, Crank C, Gear A, Gear B, Geneva Stop.

The garden gnome

The text by Hundertwasser that inspired the gnome drawings:

The absence of kitsch make our lives unbearable.

We can’t manage without romanticism.

The garden gnome symbolizes our right to dreams and our yearning for a fairer, better world.

The garden gnome is a bulwark against the soulless, nihilistic dictates of our times. Just as we hunt Dracula with garlic and crucifixes, so we use the garden gnome to drive out sterile, tyrannical dogma.

Aggressive rationalists and passive dreamers of a better, more beautiful existence part company at the garden gnome.

Long before the christian world picture, long before the gods of the ancient Romans and Egyptians, long before history was ever recorded, we were able to talk to the birds, the animals, the plants and the trees, indeed even to water, rocks and clouds, and communication brought harmony.

Thus it is written in fairy tales.

The garden gnome, together with the elves, pixies, gnomes, giants and the whole host of magical beings, is a last survivor from that distant past.

Man lives by virtue of his identity, by virtue of his memory of the roots of his being. We may now be very “intelligent”, but we have forgotten the language of nature.

Hence the small gnome in the garden.

You talk to the grass and the birds for me.

I no longer know how.

And ask nature for forgiveness for the evil we do her, and help me against the cold, all powerful enemy.

I no longer know how.


April 1990

(I found this piece of text in Harry Rand’s book about Hundertwasser published by Taschen).