9 Cylinder Radial/Rotary Engine Fidget

General
The radial/rotary engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankcase like the spokes of a wheel. It resembles a stylized star when viewed from the front, and is called a "star engine" in some other languages.
The star configuration was commonly used for aircraft engines before gas turbine engines became predominant.
RADIAL : stationary cylinders, rotating crankshaft.
ROTARY : rotating cylinders, stationary crankshaft.

A full-size display model you can find here: https://www.printables.com/model/949739-9-cylinder-radial-engine


Printing
I printed with PLA+, layer height 0.16 mm.
Use a filament with strong layer adhesion (non metallic), especially for the master-and-articulating-rod assembly.
Dimensions  87 x 88 x 19 mm.
Weight 0.04kg.


Assembly
- Assemble the master-and-articulating-rod-assembly, using the master rod and slave rods.
- Use a filament with strong layer adhesion (non metallic).
- Glue the master rod.

- Glue the Crankshaft Pin to one of the Crankshaft Cheeks.

- Place the assembled master-and-articulating-rod-assembly over the Crankshaft Pin.
- Glue the other crankshaft cheek to the Crankshaft Pin.
- Place the completed crankshaft in the crankcase.
- Glue the Crankcase Lid to the Crankcase.
- Click the pistons in the cylinders, large opening upwards.
- Align the opening in the pistons with the opening in the piston rods.
- Press the piston pin in each piston, pointing the open end upwards.
- Glue the turning knobs to the front and back of the Crankshaft.
- Optionally glue the "RADIAL" or ""ROTARY" stand to the backside of the engine.
 

Operation
Radial Engine: Hold the Crankcase. Turn a knob to rotate the crankshaft.
Rotary Engine: Hold te knobs between your thumb and index finger. Rotate the crankcase-cylinders.