Gears mesh when the teeth over lap enough that one gear turns the other.
September 10, 2012
How many teeth?
Place the axle through the x hole in the middle of a gear
Turn one gear in a gear train clock wise.
Which way does each of the gears turn?
Bushing on the back can stop the gears from falling out.
How many gear trains can you make?
Drive one gear one time around.
How many times does the last gear go?
