coils

You probably need to provide a bit more information; you know what you mean but it's awfully hard to guess. Is this a small motor for a classroom demonstration? Or just for curiosity? (nothing wrong with that...) Or is it a small industrial motor -- say the size of a refrigerator compressor? AC or (guessing) DC? Using a commutator or electronic switching? Torque requirements? HP? Does it need to meet any specs like UL or CSA?

Small, inexpensive motors are everywhere. What is driving you to the "build" side of the buy-build decision?

need

There are kits for people to make their own motors for model planes.

Ask on one of these forums about "Kits for brushless motors" or just post a your own question...

need

what

I just want to learn how it works by building one. And I will have to do a project in my last year of engineering. SO maybe, I am guessing 1/8 to 1/4 HP. I do not know which one is better AC or DC, Is one more performing then another. Or just the 3 phase AC a plus..

Ken

Are you kidding?We made one in science (high school) with nails, and copper wire.It had the size of a cigarette packet.DC motor, with commutator, shunt (not series).But the fool of a professor didn't return me the book (with the instructions).It was in greek, anyway.It's impossible to make an ac motor on your own.The principle of ac motors is the rotating magnetic field (or squirrel cage motors).There's no commutator or brushes.Imagine-to weld open the compressor of your refrigerator to have the brushes changed.It would be very dangerous, too, to use the mains for experiments.Search at your local bookstores.

-- Dimitris Tzortzakakis,Iraklion Crete,Greece major in electrical engineering freelance electrician dimtzort AT otenet DOT gr Ï "Ken" Ýãñáøå óôï ìÞíõìá news:YC3%c.6617$ snipped-for-privacy@news20.bellglobal.com...

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As far as making an AC motor on your own- it is actually simpler than making a DC motor if you have a 3 phase supply. Simply take 3 coils (such as the field coils of a DC machine) arranged in a triangle.Connect as delta or star to a 3 phase supply. In the center of the arrangement put some sort of pivot. Get a coke or beer can, drop it on the pivot and energise the coils- Voila- an induction motor. Paper clips also work. Put a small compass needle in the center of the coil triangle- Voila- a synchronous motor. Been there, done that. A single phase motor - use 2 coils at right angles and feed one through a capacitor (could use a resistor but with such a primitive construction a capacitor is better. Otherwise simply use a DC series motor on AC. Commonly used commercially- called a universal motor. The DC motor with nails and crude commutator appears in many "how to " books for well below high school level students and experimentors.

However- your comment on playing around at mains voltage is quite correct.

| As far as making an AC motor on your own- it is actually simpler than making | a DC motor if you have a 3 phase supply. Simply take 3 coils (such as the | field coils of a DC machine) arranged in a triangle.Connect as delta or star | to a 3 phase supply. In the center of the arrangement put some sort of | pivot. Get a coke or beer can, drop it on the pivot and energise the coils- | Voila- an induction motor. Paper clips also work. Put a small compass needle | in the center of the coil triangle- Voila- a synchronous motor. Been there, | done that. A single phase motor - use 2 coils at right angles and feed one | through a capacitor (could use a resistor but with such a primitive | construction a capacitor is better. | Otherwise simply use a DC series motor on AC. Commonly used commercially- | called a universal motor. | The DC motor with nails and crude commutator appears in many "how to " books | for well below high school level students and experimentors. | | However- your comment on playing around at mains voltage is quite correct.

So where is a good source of 3-phase power w/o mains voltage?