Mô Hình Động Cơ Boxer OHV 2 Xi-lanh

An overhead valve engine, abbreviated OHV  is a piston engine whose valves are located in the cylinder head above the combustion chamber.
In this model the valves are operated by push rods.
The boxer configuration with two opposite cylinders is used by motorcycle manufacturers like BMW,  Douglas, Harley-Davidson, Indian, Lilac, Zündapp, among others. 
The boxer engine is commonly used in aircraft applications because they generate a lot of power from a light engine.

The model is designed to be (de)mountable with bolts. As such the finished model is very suitable for educational purposes.

Model weight 0.3 kg.
Model dimensions 265 x 125 x 104 mm.

PRINTING
The parts should be printed on a smooth build plate.
Avoid elephant foot and over-extrusion.
I printed the model with PLA+ filament, layer height 0.16 mm. 

ASSEMBLY INSTRUCTIONS
Full Assembly instructions can be found in the file “ASSEMBLY INSTRUCTIONS.PDF”.

METAL PARTS
Four coil springs are needed for the valves, 10 mm width x 15 mm height. Wire thickness 0.6 or 0.7 mm (AliExpress).
If you wish the printed M5 bolts can be replaced by metal M5 x 16 mm Allen Bolts.

OPERATION
Turn the Cranked Handle anti-clockwise.
A Power Tool Adapter is added.