In this Assignment you will have to design a CO2 Car that can be 3D Printed. The CO2 Car will be powered by a CO2 Cartridge and you will have to use steel axles to connect the wheels of your car and washers to reduce the friction between the CO2 Car body and the wheels. Your CO2 Car Can only be Printed in one Piece and you can print your 4 wheels separately.

Supplies

To make a 3D Printed CO2 Car you will only need a little bit of things

1. CO2 Cartridge

The CO2 Cartridge will power the Car

2. Axles and Washers

You will need 2 Axles, 4 washers and 2 eyelid Screws

Step 1: Do Some Research

Before you can start designing your CO2 car you will need to do some research on how to make a fast CO2 Car. Look at how a CO2 Car works and all the things that effect the Speed of a CO2 Car

Step 2: Make a Design

Before You can Start Building your CO2 Car you will need to make a design. You can use TINKERCAD to design your CO2 Car. When you are designing your CO2 Car make sure that the hole for your CO2 Cartridge your Axles holes are offset by 1-2 mm so that the CO2 Cartridge and the Axles will fit properly into the holes.

1. Research some designs

Before you start designing your CO2 Car look for some ideas online and explore CO2 Car Designs.

2. Make A Drawing

Now that you have some ideas, make a sketch of the CO2 Car you want to make. You can make a Isometric Drawing and a Orthographic Drawing of your CO2 Car.

3.Start To Design Your CO2 Car

Now it's time to start designing your CO2 Car on TINKERCAD. When you make Your Axle Holes and The Hole for the CO2 Cartridge make sure you offset the holes by 1.5 mm so everything can fit nicely together in your CO2 Car. Also make 2 small holes at the bottom of your CO2 Car the 2 eyelid Screws.

Step 3: F1 CO2 Car

This is a F1 CO2 Car

Step 4: Shell CO2 Car

This is a Shell CO2 Car

All the wheels of the Car are in the body of the Car so the wheels will not cause any Drag and the car is very aerodynamic.

Step 5: F1 CO2 Car

This is a F1 CO2 Car

Step 6: 3D Print Your CO2 Car

Now it's time to 3D Print your CO2 Car

1. Export your CO2 Car from TINKERCAD

Now its time to 3D Print your CO2 Car. You can export your model in TINKERCAD as a .OBJ file because depending on how your CO2 car is shaped you might see some sharp edges on round surfaces in your model if you export you model as a .STL File and the .OBJ file wont have any sharp edges on round surfaces on your CO2 Car.

2. Slice Your CO2 Car

When you 3D Print your CO2 Car your slicer settings should be 4 outer walls, 4 top layers, 4 bottom layers, 40% infill and you should print at a 0.1 mm - 0.2 mm layer height, which will make your CO2 Car Strong and Impact Resistant. When you Print your CO2 Car Wheels your slicer settings should be 4 outer layers, 4 top layers, 4 bottom layers, 100% infill and you should print at a 0.3 mm layer height.

3. 3D Print Your CO2 Car

Step 7: Assemble Your CO2 Car

1. Assemble the Axles and Wheels

To assemble our CO2 Car first you have to put your axles in the axle holes and see if they spin freely and if they don't you can use a 0.125 In drill bit to drill out the axle holes and the axles should spin freely. After that you can put the axle into the axle hole and then on 1 side you can put a washer and then a wheel. After that check to see if the Axle is too long on the others side. If the Axle is too long then you can cut the axle to the right length with a hacksaw. After you cut your Axle to the right length then you can put the Axle in the Axle hole, then you can put a washer on both sides of the Axle and then after that you can put the wheels on both sides of the Axle.

2. Put in the 2 eyelid Screws

to put in the 2 eyelid screws you can just screw then into the 2 small holes on the bottom of your car and if the holes are too small on the bottom of your car, you can use a 0.0625 In drill bit to make the holes a little bigger.

3. Assemble the CO2 Cartridge

When you put your CO2 Cartridge into your CO2 Car make sure it has a very light press fit. If your axle hole is too small you will either need to sand the hole down if there is only a little bit of material to remove or you can use a file and then sandpaper if there is a lot of material to remove. Make sure that the CO2 Cartridge has a light press fit, but you can still insert and remove the CO2 Cartridge.

Step 8: Race Your CO2 Car

You can Race your CO2 Car by puncturing the CO2 Cartridge with something sharp and the the escaping gas will make your car accelerate very fast and reach a high top speed. You can set up a track with a small line of rope going from one end to the other and put the rope through the eyelids of your CO2 Car, which will act as a guideline to make sure your CO2 Car goes straight down the Track. Make sure you are wearing safety glasses when you are racing your car and puncturing the CO2 Cylinder.