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Need help choosing a dc motor!! Answered

My students are building model cars our of balsa wood that move b/c of a dc motor.  All of the motors I have are burning out - they can't run long, I used to have a dc motor that started out slow, built up speed and then ran fast and for a looooooong time.  Does anyone know what type of motor i'm talking about?  please help.....i gotta get them asap.  thanks!




Burning-out? With smoke?
Too much power: use fewer batteries (or force the students not to overdrive them upon penalty of disqualification / no marks)



8 years ago

I'm not quite understanding how you intend to power these cars, unless its some sort of brush contact connection similar to a slot car.
Irrespective of this, I would suggest a small3-6 volt DC motor. You can get them for less than a dollar apiece if you buy in lots of 50 or more.
Here is a link to one site that sells in bulk, (there are lots of others out there too):


Basically it sounds like you are seriously over-running these motors - they WILL only handle a certain supply voltage !

Where are you in the world ? As always that affects our recommendations of where to get whatever !


THIS is the sort of motor you'd normally use for powering a small, light balsa model.  This type is meant to run off 3V to 6V or so.
How do the cars run freely if you're powering them from a fixed supply?

If these balsa models are 6" or so, you'd be much better off powering them with a battery pack like THIS which will give you 4.5V. It would also let the model run free rather than being tied to the power supply.

You need a small 30 volt dc motor.  Or find out the voltage of the ones you are using and limit your power to that.   The motors you have been using may vary from 1.5 volts on up.

 It's Patti again - just wanted to let you know that we're powering this motor using a 0-30VDC power supply - I'm sure that makes a difference.  Thank you!!!

patti :)