There are generally two micro-helicopters ( indoor ) in the RC market. I have already planned to buy one of them as they can fly inside the living room and even take off on ours hand. Unlike those operated by gas, these electric helicopters are very clean and give out no terrible noise at all. In one nightfall, I visited a web site, which is about how to make a hand made RC helicopter. I was totally impressed and started designing my own helicopter. Here is my helicopter:
Step 1: MAIN BODY
The circuit board is cut to the rectangular shape as above( 98mm*12mm). As you can see, there is a hole on it which is used to house the main shaft holding tube as below: (2)
Brushless DC, Brush DC, And Stepper Motors From Allegro.
Step 2: MAIN SHAFT
Up to now, the basic structure of the helicopter is completed. The next step is to install the gear as well as the motor. You can take a look at the specification first. The gear I used is from Tamiya gear set that I bought long long time ago. I drill some hole on the gear in order to make it lighter and have a better look.