This project is an offshoot from the development of the Flip Face project, it features a pair of gears. One with forty teeth, one with eight teeth. Members can download the parts from the link above, thank you for signing up!

Print out the parts onto thin card (230 microns / 230 gsm) Score along the dotted lines and cut out the holes before carefully cutting out the parts.

Glue the two large gear squares back to back but with one rotated at ninety degrees to the other so that the grey stripes on the back piece on the picture above would be horizontal.

Glue the teeth to the gear body using the grey areas for alignment.

Leave the last section of teeth unglued.

Roll round the gear body and glue it together.

Glue the last tooth down. Carefully shape the gear body so that it is as round as possible.

Apply a thin layer of glue one of the gear sides and fix it to the gear body using the grey gear  outlines for alignment. Press it down on a flat surface for ensure the glue is gripping well.

Slide in the axle.

Fit the other side into place making sure that everything lines up.

Glue the stiffening parts to the front face of the large gear.

Flip the gear over and glue the remaining stiffeners on the back. The combination of vertical and horizontal stiffeners help keep the gear flat as it rotates.

Fold round and glue together the two side pieces as shown above. Note the the triangle tube sections top and bottom are right-angled triangles.

Assemble the handle in three steps.

Fold up the two sections of tube.

Fold them one inside the other  then roll the long tab round and glue it down.

Glue the axle into the large gear lining it up with the grey centre line. Glue the two axle supports  into place front and back, these will both support the axle and keep it lined up straight.

Glue the two washers into place lining them up with the grey lines on the axle.

Carefully cut out the teeth to complete the big gear.

Fit the two box pieces to one of the box sides using the grey areas for alignment and drop the eight toothed gear into place.

Fit in the second gear then glue the other box side into place.

Glue the handle onto one of the shafts – the choice is yours. If you glue it to the small gear, the large gear will turn only a fifth as fast as the large gear. If you glue it to the large gear then the small gear will spin at five times the speed!