Vertical pendulum, Move the box and the main shaft at the front rocks up and down. This mechanism is destined to be used in the heart of a paper animation, perhaps a hopping frog or a moon walking spaceman. Build the project and bring it alive with your own character!

As usual, members can download the project for free, thanks for signing up. Non-members can download the parts for £2.50

Vertical Pendulum in action.

Print out the first two parts sheets onto thin card (230 micron / 67lb), the third sheet contains hinges, it should be printed onto standard 80gsm printer paper. Paper makes a good flexible hinge.

Glue the two pendulum pieces back to back then glue down the two side flaps.

Glue the paper hinge into place.

Fold the feet round and glue them down. Note that the creases are valley folds.

Glue the two sides to the grey areas on the base. Note that the writing faces towards the longest foot of the base.

Assemble the two struts and glue them into place on the grey areas.

Assemble the top piece and glue it into place using the grey areas for alignment.

Glue the pendulum so that it hands from the front strut.

Assemble the top link as shown. Note that the tongue is completed by folding over the tab and gluing it down to make double thickness card.

Assemble the bell crank as shown. The tongue is the same as the previous link. Glue two paper hinges into place as shown.

You’ll need four coins as weights. UK 2p coins are perfect. 25mm in diameter, 7 grams in weight. Wrap each pair of coins tightly in an off-cut of card as shown.

Glue the coin packs to the pendulum front and back.

Glue the bell crank to the lower strut

It needs to be free to rock back and forth.

Connect the upper link to the upper strut with a paper hinge.

Thread the vertical shaft onto the two tongues and lock it into place by gluing the two tabs into place.

Glue the lower link to the front of the coin pack using a paper hinge.

Connect the lower link to the bell crank via the other paper hinge so that the top of the bell crank is sitting horizontally.

There it is! Move the model and the vertical shaft rocks gently up and down. Next step, add your own character!