This is a printable knob designed for the crank handle of a GasBoy 1230c rotary hand-operated fuel pump. It should work with any 1200-series GasBoy pump as well as in any application where a 5/16-inch axle/bolt is used to retain the knob. This is designed to fit snugly on a partial-thread 5/16x5" bolt when the 1-inch-long thread is fully engaged. It uses standard 5/16 flat washers as end caps, though if you desire a smoother operation it could be easily modified to accept a bearing of your choice. The handle is quite chunky and is designed for operation in all weather, with or without gloves.
Maker Geeks PETG
however you use this hande, choose your filament appropriately. PLA does not survive outdoor conditions very well, and due to it's brittleness may not be an ideal choice for this application. PETG, or ABS are probably ideal for most uses.