About this 3D model
Main Gear Box (MGB) for Helicopter driven by 2-Engines has complicated gear train in inside.To understand this mechanism, I designed the internal visible model.There are many different designs for each actual helicopter, therefore this model is just a sample. The features of MGB are; 1. 2-Engine Inputs 2. 1-Tail Take-Off Output (moved to the opposite side to clarify) 3. 3-Stage Reduction (including 1- Planetary Gear) and 2-Stage Reduction + 1-Stage Increase Note: (1) Gear types used in this model are changed due to ease designing and printing. Bevel Gear → Spur Gear + Face Gear, Helical Gear → Spur Gear (2) Clutch and Accessary drives are omitted at this time. Download files includes;-files: STL Files-images: Parts Breakdown and Sub-assy photos for assembly Aid.-Excel File (ZIP): Parts List with related hardware Purchase Parts Information;-Bearings; No metal Ball/Roller Bearing is used. Then some grease for plastic is recommended for lubrication. -ABS Tube See Parts List -Screws and etc. Micro screws M1.4x3.5L - 5 ea - Direct screw-in to 1 mm diameter hole (No nut), Screws M2 x 6L - 20 ea, See Parts List Screw M2 x 25L and Nut+ Some tube for Turning Handle (Optional) Printing parameters recommended (0.4mm Nozzle is used)- Gears: 0.2mm Layer Height, 100% infill- Bodies: 0.2mm Layer Height, 40% above infill (for threads) Raft and Support: Depending on your experience Assembly Points- Standard Skill (such as Drilling, Tapping, Filing, Tightening, Painting and Gluing etc.) is needed and perseverance too.- For gears: Deburring (removing the sharp edges etc.) is very important for smooth rotation.- If you do not give up to finish the gear teeth, then you can get the smooth rotational MGB model.- Good luck!! Total Net Print Time: Approx. 28HR- (Estimated as case of PLA, 0.4mm Nozzle, 0.2mm Layer Height, 40% infill and No raft and support) Note: When at actual print, each parameter should be adjusted by your experience. 【Optional Parts】TTO drive is moved to same side as Engine input. See photos.- Body-Mid201.stl → Body-Mid901.stl I do hope your success!!