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Are Cheap Toy Motors any good for helicopters?- oh my god you are stupid.How can you expect the scale to change when the stream of air that provides the lift is pointed at the scale...
- very good video. helped my group get an A++. thnx. this is the good wan
- great work i hope further progress
- Longer copper wire in the motor, more speed
- hello sir.i saw that the mini motor of toothbrush works and it's havier.so why you don't make a mini drone with four(4) similar motors.because i have a feeling that it will work.and im sorry for my bad english language.salam
- where do u find those motors
- hey grandad can you try and make an quad coptor with these small motors and make it lift off, please try it if you can
- but its damge after few time the best motor to used it  https://www.youtube.com/watch?v=2wNksnuP_Eo
- you need to use LI-POLY battrey because it's less heavy and powerful as the 9V battrey.... but using LI-POLY battrey is danger because it may explode !!
- This is not good at all ture

- You need to note some things in making a copter voltage,propeler and weight are some of them
- I'm trying to build a helicopter with a handmade propeller and a DC motor about the size of the second motor you used (4:05) when I use 9 volts it feels lighter, but when i start increasing the voltage, it feels even lighter, like it's ready  for lift off, but I'm afraid it might burn the motor, so what should I do, make a bigger propeller?
- Gear? like an airplane transmission gear for rc?
- Could you make a boat with a motor to run it instead of a nose/hair trimmer
- You doing it wrong, the fan push the air down trying to lift the weight up... So its still record the same weight. 
- Grandad, I too am a grandad and do enjoy myself  playing with my  grandson.  Please allow me to explain  why your weighing machine is not registering properly, for I feel that you are not considering something in physics which is very important.   All the downward slipstream from the propeller is going down fast and it is hitting the weighing machine. The surface of the weighing machine is bringing all the slipstream to a stop and so this is a change of momentum producing a force on the weighing machine, So if there is a loss of weight on the motor , well the weight of the air pushing down on the  weighing machine is equal to the loss of weight, so there will not be any reading on the weighing machine.

Let me put it another way. If you weigh a cage full of birds, the weight of the  cage will be the same whether the birds are stationary or whether they are flying, When they are flying the  air being pushed down will hit the bottom of the cage with the same force as the weight of the bird. That is the law of phyiscs.     Now if the bird was free or your motor was away from the weighing machine well then there will be an indication of the loss of weight that you are expecting.       

I am sorry I have to point this out to you but you are not conducting  that particular experiment properly. Now if you had to arrange for a lever system such that the slipstream  pushed down by the propeller  will not come anywhere near the top surface of the weighing machine, you will get the readings you are expecting.  During your experiment none of the slipstream on the propeller must go anywhere near the surface of the weighing  machine.

I hope that this is clear enough, and I apologise if I have interfered with your good videos , I am only trying to help.
- Please try and make a very large pop pop boat with more than one engines and do a test on diffrent boilers to see Whitchurch is best 
- This is a great video! i have been saving the toothbrush motors , now you gave  them a purpose .
- Cool Test Rig.