Remote controls cars are now widely available, however there's one astounding model that one can scratch-build. It measures merely 2inches long but is equipped with proportional control system including 12step steering control, headlights and more!
Below is the complete list of materials required.
Step 1: Materials Required
1.5mm Balsa wood
Printed shell template
2ch 2.4Ghz micro Rx
1S 3.7V 50mAh Lithium battery
4x12mm coreless motor
Micro plastic gears
25-70ohm Actuator coil/magnets
0805 SMD white LED
CF/ steel axle rods, 1mm diameter
Step 2: Making the Chassis and Geardrive System
The shell is made by printing a paper car template onto a 200gsm glossy paper.
Next, Ive glued the LED's onto the shell using epoxy and soldered them is series using enameled copper wire.
Making the chassis:
I have used 1.5mm Balsa as its easier to work with but it can also be made using plastic. The rear wheel axle with a spur gear is slipped into a tube(preferably plastic with smooth finish to reduce friction) and glued onto the base.Now the wheels are firmly fixed onto the axle. The same procedure goes on for the front wheels too except that, the axle is kept stationary and wheels are free to rotate about the carbon fibre rod.
An off the shelf actuator can be used for steering the model, else the same can be made by making a small coil with resistance of about 25-70ohms and placing a neodymium magnet in it. The ends of the coil are directly soldered onto the receiver.
Step 3: Mounting Receiver, Motor and Battery
A 4x12mm coreless motor with pinion gear is glued onto the chassis by aligning it with the spur gear on the rear axle.
The wires of the motor are rooted to the speed controller and then to the receiver.
After ensuring the functionality of every control, its time to fix the battery and receiver in place by either using tape or hot glue. This can sometimes get tricky with bulking stuff like a larger battery, receiver or longer connecting wires, they need to be squeezed in order to accommodate in the given space.
Step 4: Done!
The chassis and the electronics are then en capsuled by the shell. Make sure that there's a little clearance between the wheels and the shell.
It's now ready to run!
Here's a short video of the test run.