Gear

An intriguing model for you to download, print out and make. The gear model uses only cardboard to make this fully working mechanisms.
The download consists of all the parts and fully illustrated instructions ready for you to print out. You will need glue (PVA -white school glue) some scissors and a sharp knife.
teeth There are two gears in this model. Both are constructed in the same way. Start by lining up the points of the two red arrows and glue down the first fold of the teeth. Glue the remaining teeth into place using the purple arrows to help with alignment.
core Glue together the gear cores as shown.
gear Start with the end of the teeth with the red line. Glue this to one of the tabs on the core. The red line lines up with the centre of the core, the end of the tab lines up with the edge of the teeth. Allow the glue to dry then roll round and glue the teeth onto the core to complete the gear.
shaft Fold round and glue together the two centre shafts as shown here.
gear Carefully thread the completed shafts into the gears lining up the centre of the core with the grey line on the shaft. Make sure that the shafts and the gear are parallel with each other as the glue dries. Glue the washes into place on one end of the shaft. Slide the other washer into place but do not glue it yet.
box Fold round and glue down the flaps on the main part of the box making a triangular section. This will add strength to the box.
boxGlue the two parts of the box together as shown. Fold down and glue the four flaps top and bottom. Glue on the back of four end flaps and glue them down to the inside of the box. Assemble the handle as shown on the parts page.
box Carefully fit the two gears into the box. Threading the end of the shaft with the unglued washer into place first is the easiest way to do this. Once fitted glue the last of the washers into place. Finally add handle to complete the gear model.