3D Printed in Line Twin Cylinder Engine
Introduction: 3D Printed in Line Twin Cylinder Engine
This instructable was created in fulfillment of the project requirement of the Makecourse at the University of South Florida (www.makecourse.com).
The in line twin cylinder engine has many applications across various industries including powersports for which there is an entire class of racing devoted to this engine known as the Motoamericas twins cup races.
Step 1: Gathering Materials
3D printer requirements:
* Capable of 220 degrees Celsius nozzle temperature
* Heated bed preferred
* minimum build volume 150mm X 120mm X 125mm (width X depth X height)
Printer Used: https://flsunofficial.com/products/super-racer-sr-...
PLA: https://www.amazon.com/Printer-Filament-SUNLU-Dime...
Assembly Lubricant: https://www.amazon.com/Royal-Purple-Max-Tuff-Synth...
12 Gauge copper wire: https://www.amazon.com/PHAT-SATELLITE-INTL-Protect...
Fasteners:
* M4 x 0.7 x 25 countersink flat (10)
* M3 x 0.5 x 12 (8)
* M3 x 0.5 x 16 (4)
Electronics
* Arduino Uno: https://www.arduino.cc/en/main/arduinoBoardUno
* Breadboard: https://www.amazon.com/Breadboards-Solderless-Bre...
* Wires: https://www.amazon.com/TOAPPNER-Multicolored-Brea...
* IR receiver with remote: https://www.amazon.com/KOOBOOK-Infrared-Wireless-...
Step 2: The Engine Block
The engine block houses the entire rotating and oscillating assembly of the engine.
The design features an open front for ease of viewing for the rotating crankshaft assembly as well as the oscillating piston assembly
On the rear of the engine block are marked out regions for the Arduino and breadboard to be mounted.
On the sides of the engine there are holes for the input shaft of the DC motors as well as holes for the M4 fasteners that hold the motors to the engine.
On the underside of the engine there are pre-marked holes for the M4 countersunk fasteners that will hold the crank journals to the engine.
Step 3: The Engine Base (Oil Sump)
The Engine base serves a dual purpose. its main purpose is to lift the engine off of the table to allow the crank arms of the crank shaft to rotate without colliding with the table. Its secondary purpose is to collect any oil that may drip down if the user opts to utilize any kind of low-viscosity lubricant such as engine oil.
The base also serves as a conduit for the IR receiver to be wired to the front of the engine such that it can receive unobstructed signals from the remote.
This base also contains the second mounting point for each of the DC motors.
This part should be printed with a relatively wide brim to prevent the corners from lifting from the build plate
Step 4: The Rotating Assembly
The rotating assembly of the engine is responsible for delivering the power from combustion to the output shaft of the engine in a real engine. In this case it will be moved by the DC motors mounted on the ends of the crankshaft.
The crank shaft is best printed on its sides with supports for 45 degree or more overhang. 858
Concentric style supports proved to be relatively easy to remove compared to the other options.
the piston is best printed upside down to avoid the need for supports on the hollow interior.
The connecting rods are best printed upright to avoid the need for excessive supports. it is strongly suggested to use a large brim for the connecting rods as they are long and slender and are therefore prone to lifting due to the small contact surface at the build plate. If bed adhesion issues continue, use a raft.
Step 5: The Electronics Housing
The electronics housing is responsible for concealing the control system of the engine.
This part should be printed upside down (large planar face down towards the build plate) to eliminate the need for supports.
The housing should also be printed at a fine layer height (0.15 mm worked well) to eliminate the need for support in the overhang. The need for support is eliminated by the fillet radius which is large enough to support the next layer if and only if it is printed with a fine layer height.
The concentric pattern for the base layer paired with a brim proved to be effective at preventing the lifting of the corners.
Step 6: Printing the Parts
Using a brim is highly recommended for proper build plate adhesion for all parts. 646