3-coil DC Motor with split-ring commutator

Final project from a design paper at MIT Auckland. Built at home - tested in the lab using tachometer and oscilloscope. Max speed = approx 10,700rpm using tachometer (32,268rpm/3 coils = approx 10,700rpm) with 12V bench supply, drawing average 0.59A. Would've liked to measure torque output also, but didn't get round to it.

Category:

Science & Technology

Tags:

• motor
• coil
• solenoid
• magnet
• neodymium
• rare earth
• commutator
• split ring
• DC
• current electric
• electricity
• engine
• physics
• electromagnetism
• faraday
• induction
• volts
• battery
• iron core
• rotation
• speed

[prem9740]

WATCH THIS SPACE - soon to come is another video with a more complex 6-pole (6-coil) DC motor, complete with video footage all processes of construction. I'm about halfway through building/videoing the motor at the moment.

[alecpolo93]

How much did this cost you?

[prem9740]

@alecpolo93 Pretty much all I needed to purchase were the neodymium magnets. That came to $40, but you could do it with half the magnets I used, so about $20. The rest of the stuff I had lying around the place at home - bearings, wire, PAL aerial plug, etc. My guess is that if you were buying the stuff yourself, it would come to around $40 or $50.

[pcangeldust]

what are the factors limiting the efficiency of the motor? friction between commutator and shaft only?

[prem9740]

@pcangeldust No. To build a motor of this kind with maximum efficiency, you would need to take into consideration the gauge of wire used (and therefore the resistivity of the wire), number of turns in each coil, shape and orientation of permanent fixed magnets, quality of bearings for armature, material used for brushes. If you wanted to get really serious, you could surround the whole motor with a steel case - this helps direct the magnetic field in the correct direction from memory.

[prem9740]

@onedaysnotice44 hi there, I sent an email to the address you gave me in your PM. Did you see it? If not, let me know.

[alecpolo93]

@prem9740 please send me the PDF i need to o a physics project lol thanks a lot!

[onedaysnotice44]

hi did you see my pm? can you please send me the report? thanks :D

[personr18]

best homemade simple motor iv seen.WARNING dump question alert:whats a commutator

[prem9740]

@aniarya22 Hi there, thanks for comment. Commutator is divided into 3 parts - I used a very small cutting disk on a Dremmel tool to separate it into 3 parts of 120 degrees. Check out my other video on here specifically about the commutator.