This is a way to make an analog pot spin all 270 degrees while only having the control arm move about 90-100 degrees.  The gearing is almost 1:3.  I'm using it as a throttle control for an RC Arduino build.  

You will need

2 M3x8 Screws

1 M3x14 Bolt

1 M3 washer to place between the large gear and the housing.

I used PETG but I'm sure it would be fine with PLA, ABS, or any other filament.  20% infill.