Simple dc motor with forward/reverse and self starting

Picture of Simple dc motor with forward/reverse and self starting
Grandson Nicholas and I developed this simple motor for his school project. We checked the web for ideas and then evolved this motor that has a number of unique features that make the motor easy to start and run.  The motor also features a forward-reverse and speed control.  

The motor armature rotates due to magnetic pulses created by a pulsating current that flows through the armature coil - these electromagnetic pulses interact with the rare earth neodymium permanent magnets (the "field" of the motor) and cause rotation to take place. The neodymium magnets are mounted on the sliding "direction and speed control" bar. Sliding the magnets under the armature gets the rotation started. 

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Step 1: Video with operating and build info

Step 2: Materials and tools

Materials used
  • paper towel
  • paint can stirring stick
  • 2 solid brass ceiling hooks 2-9/16 inches
  • D battery - used for wire winding form
  • 6 feet #22 enamelled magnet wire 
  • 3/4 inch thick soft wood base approximately 3-3/4 x 12 inches (pine works good)
  • 4 neodymium magnets approximately 3/4 inch diameter
  • double sided tape
  • 4 AA alkaline batteries 
  • battery holder - connects 4 AA batteries in series for 6 volts
  • 4 push pins
  • 2 plastic beads
  • small piece of plasticine (not shown) 
Tools used
  • paper stapler
  • pencil
  • small awl or small Philips screwdriver (a drill and bit would work as well)
  • wire cutting pliers
  • utility knife
  • speed square or plastic triangle 

bobschukes made it!13 days ago

This was a great project, thanks for posting. My son and I made it for his school science fair project. We made a "head to head" model, one with 3 volts, and one with 6 volts to show the difference in rotor speeds with higher/lower voltages. We mounted the motor sticks with mirror clips, and used a metal coat hanger to make custom bent posts for the rotors. This eliminated the need for clay to hold the rotor in place. we also soldered the battery wires to the posts and epoxied the posts into the base.

nlinventor (author)  bobschukes13 days ago

Wow that's great, thanks for letting me know!

ptroolines11 months ago

Very clever, and interesting use of some simple items. Thanks for sharing your motor.

nlinventor (author)  ptroolines11 months ago

Thanks ptroolines!

moimoipalamoi11 months ago

I like the way you use the ceiling hook to support the coil. And it is a detailed instructable too in my opinion! I think i'm gonna make another one following your guides! And maybe you could also use paperclip as another easy to find yet cheap substitute for the ceiling hook. But it won't be sturdier as the ceiling hook, also i'm pretty sure that the neodymium magnet will be attracted to the paper clip.

nlinventor (author)  moimoipalamoi11 months ago

Your right moimolpalamoi re paper clips. Another idea that I didn't try yet is using a long brass wood screw instead of the brass ceiling hooks. If you can find a slotted screw you have a great ready made holder for the axles. Plasticine would probably be needed here too but the screws would likely be cheaper than the hooks. I paid about $1 each for the hooks I used in this instructable.

rimar200011 months ago

Very interesting design, and good construction.

nlinventor (author)  rimar200011 months ago

Thanks rimar2000!

gholam11 months ago