Here is my first upload. I had to make this for school It is a 2 cylinder spool valve engine it should run but if it doesn't i can make changes to it. ill get some printed pictures as soon as i can. I am probably going to simplify this to use less plastic because right not it is a bit excessive for just a model(I am making a vehicle that moves with compressed air that runs along a track. watch for parts for that e.g. transmission differential frame, the like.). If you have any questions just leave them in the comments The cross-section should be pretty clear but if not then just leave a question. If you want it full sized you have to scale it by 1000 in slic3r or 10 in repieter host. 4 supports_fixed 1 base(repaired) 1 sleeve_and_head_assy 2 piston 2 connecting_rod 2 crank_pivot 1 bottom_head 2 crank_pivot_pin 1 crank 2 bushing_out 1 bushing_mid 2 spool 2 valve_rod 2 spool_pin 2 cam_linkage 2 cam_linkage_pin 2 connecting_rod_bottom 2 cam_linkage_bottom 2 intake_valve_cover 1 intake_manifold 1 PTO 2 piston_pivot 2 eccentric 1 flywheel Ill have more precise directions when i make it my self.