This is a simple gear system that can be entirely 3D printed with no supports. It is intended to demonstrate to younger children how gears work and what their functions are.
To assemble the gear box you will need to print:
2x drive gear
(the files are named accordingly)
A small amount of glue may be necessary at the point where the pins join the base since they are smaller than the base holes to ensure that they account for any error margains on certain printers.
The two drive gears go at each end of the base and are connected using the 'pin1' file. The two gears go in the middle and are connected using the 'pin2' file.
I designed this simple gear mechanism because I think that simple models like this really help children, or people of any age for that matter, to really grasp the concept of simple mechanisms. This is a two way gear system because if the user turns the different tnd cogs, the opposite end cog will either spin quickly or slowly depending on the gear direction.
I think this design is suitable for the HOPE3D because it is small, simple can be mass produced by anyone with a 3d printer. There are no supports and the design is all small enough to be printed on any convensional home 3d printer.