Introduction: How to Make a Strong Genorator

Picture of How to Make a Strong Genorator

this project came to me after i had noticed that there is not many differences between a ac motor coil and a dc motor coil. well the only difference was the size. so i got started!

the tool list that i used is quite extensive and some exeptions could be made the tools i used will be listed below
drill press
philips screw driver
a black and white marking pen
hobby knife
table saw
hack saw

plastic block (size will vary to the size of your motor coil)
AC motor coil
brushes and springs (be sure that they are from the same motor coil)
key stalk
sheet metal
small pieces of tin

Step 1: Step One (frame)

Picture of Step One (frame)

first you wnat to organize what you want to do first the frame or the motor. i started with my frame. i would show you step by step the drilling and welding but i had to make it first to make sure it works

the first thing that i did was took the key stalk and cut they in two lengths and put the two smaller pieces parallel and the longer pieces on top so they are on the edges of the smaller pieces. double check to make sure that it is square then weld it together. then take the sheet metal and weld it to the bottom of the long key stalk. then with a piece of sheet metal that is the same width as your plastic block. center your plastic block on the piece of metal you cut and mark the metal with the white marker were the plastic ends on each side then drill a small hole in each corner inside were you marked for your screws. keep the holes as close to the corner as possible  to avoid having a screw go in to were you will have to drill on the block. then square up the plate on top of the long key stalk closer to the middle and weld it down

Step 2: Step 2 (drilling the Block)

Picture of Step 2 (drilling the Block)

now to work with your block first cut it to the size you will need it. take the black marker and draw a X from corner to corner on the large face to easily find the center of the block. now that you have center found, drill a piolet hole then drill a hole the same size as your motor coi.l after you have done that check your clearacne between the coil and the hole you just drilled i gave my self 2mm clearacne you might have to use sand paper to get the extra clearance.
now flip the block on its side and X 2 sides then drill a piolet hole and then drill a bigger hole that is a little smaller then the magnets and drill all the way through both sides of the block then rotate it and do the same thing to the other side. once all 5 holes and drilled put it on the lathe and shave away the plastic till the magnets fall in. make sure to leave a thin lip so the magnets don't fall through to the coil.
now take the hobby knife and clean up all rough edges  

Step 3: Step 3 (drilling the Frame)

Picture of Step 3 (drilling the Frame)

ok now that you have your frame built and your block drilled. now you need to finsh drilling on the the frame to put it all together
the first thing that you want to is take the same size of bit that you drilled the screw holes. then drill in the screw holes and through the bottom plate. flip the frame over and take a bigger bit and drill only through the bottom plate so the screw heads will go through

Step 4: Step 4 (finish the Block)

Picture of Step 4 (finish the Block)

this part is important part in making the motor work proporly
you must arrange the magnets two of the 4 magnets side by side as - and the and the other two side as positive. i learnt that the hard way the first time i did it i arranged the magnets +-+- instead of --++ .once you have that done that fill the hole up with silicone so that they will not fall out

Step 5: Step 5 (put It All Together)

Picture of Step 5 (put It All Together)

at this point you are almost finished.
after the silicone is dried, place it on the metal piece that you cut to the width of the block and screw it down tight but don't strip the block now set in the motor coil temporarily to mark directly below the end of the shaft on both sides now remove the coil and drill a hole were you marked with a bigger bit than your bolt so that you have a little movement to adjust the motor coil to get center with no rubbing on the plastic. now put your motor coil in the block, slide the tie rod ends on the shafts of the coil. put one washer on the bolt and put it through the plate then put one or two more washers on then the nut and then the tie rod end. do this to both sides. the using slight movements center the coil in the block so it spins freely in the block, make it hand tight until you have them both were they need to be. now take a couple wrenches and lock the bolt (what i mean by this is turn the nut down towards the plate with one wrench and turn the bolt up with the other.

well thats it... almost in order for the motor to work you need power and something to transfer the power to the coil. the brushes!! now you need mount the brushes for this part i didn't do any thing special i drilled a hole in a scrap plastic just large enough to fit the spring and brush then cut a slit in the plastic that goes down to the hole then slide in the tin pieces so the spring presses against the tin and the brush when its on the coil then i screwed it to the block


HoldOnTight (author)2012-08-21

Thanks for putting your ideas into a prototype. I think I have some old but big rotors from dead AC motors lying around and it would be cool to build a generator or motor from scrap parts. DC motors and generators are SOOOO expensive compared to their AC counterparts. Your idea has value! Thanks for sharing. You got my vote!

HoldOnTight (author)2012-08-21

Thanks for putting your ideas into a prototype. I think I have some old but big rotors from dead AC motors lying around and it would be cool to build a generator or motor from scrap parts. DC motors and generators are SOOOO expensive compared to their AC counterparts. Your idea has value! Thanks for sharing. You got my vote!

agedesign (author)2012-08-18

i did do testing on this genorator it was produsing 3v at low speed thats hand cranking it and 12v at top speed spinnig it with a drill
i still havent seen its top speed as a motor yet but its like a bushinged motor . not ment for long use but if you put bearing holders in it and bearings it might last a long time and be useful

fastrat2000 (author)2012-08-17

Nice I like that all the parts are common ez to get, and fairly ez to set up, I sure it works but wonder how well. Some testing would nice. But one thing I don't see is cooling this type motor have a lot cooling, some mods you may like to play with is clocking the brushes around some should change where it make its power at.

I know some don't like the brushes or that its DC. At this scale DC is grate if your powering some needs DC, there loses in AC to DC conversion too. More testing I think is need see if make power that could useful even if not up to par with some AC gens if cost less and ez to make it still may have a place, or maybe just some thing fun play with.

Now what you done is take U type motor and use it core to make a DC motor, or DC gen if you like, U type motor don't have the back EMF, why they are used for high speeds, so your core likely rated 10-20K rpm that maybe good, but does this make good DC gen core, it can turn high RPM, but what it make power wise and at what type speed and load, I think a lot more testing need done to say

Thanks for the build 1/2 want to build one just try it I could a flop but could gold too, Tesla didn't get his at the time.


databoy (author)2012-08-16

This project should be entered for the Darwin Award. Someone with no electrical knowledge will attempt the build and electrocute themselves. It is called back EMF.

AC was invented by Nicola Tesla to overcome the inefficiencies of DC generation. Sliprings are far more reliable than any DC commutator design. You will never match the power to weight to efficiency and cost using a DC commutator over an AC slipring design. Also the placing of the brushes on a commutator is very critical otherwise you will experience severe arcing.

If you want to build a very efficient generator/alternator use a car or very heavy duty truck alternator. They all generate three phase AC which is rectified to DC.

manuka (author)2012-08-16

Agreed! Slip rings, which ride on smooth surfaces, don't hence have to experience the rasping wearing action of brush to segmented commutator. They can be extremely durable, & car alternators usually outlive the vehicle!

Automotive alternator slip rings however only carry modest currents (~a few Amps to energize the rotating armature), with the 30A range output taken from the fixed surrounding coils. This is low voltage 3 phase AC, which 6 diodes built into the alternator rectify  to DC for battery charging.

Go to a auto scrap yard, grab an alternator & pull it apart - it's very educational!

dawp (author)2012-08-16

Most universal appliance motors, electric drills, saws, hedge cutters, roto-tools, mixers and blenders and vacuum cleaners are of the brush-commutator design. So are the motors used in trolleys and diesel engines. They use this I guess because this type of motor is capable of light load high speed and low-speed torque. I don't understand the purpose of this project?.

rimar2000 (author)2012-08-13

I have read that a motor with brushes works indifferently on AC or DC.

I never did the try, because all AC motor I seen are 220 V, and all DC motors are 12 V or less. And all my power sources are 220 AC or 12V or less DC.

agedesign (author)rimar20002012-08-13

well i haven't done any reading on this project or heard of it running indifferently but i have done repairs on ac and dc motors.
the dc motors use a fixed magnetic field with magnets while ac motors use the alternating to have a electrical endused magnetic field using magnetic wire
so thats why i think that there is a difference between the two types of source with the type of motor

temper (author)agedesign2012-08-13

Actually all motors are really AC motors - that's why there is a commutator (the thing the brushes slide across) - this turns the DC into AC through the coils (brushless DC motors do the same thing electronically).

What you have there is a universal motor - i.e. one that will run on both AC and DC. You have just turned it from a motor with an electromagnetic stator to one with a permanent magnet stator.

Actually, if you could replace the commutator with slip rings and powered it from AC you would have a synchronous motor - something really useful.

agedesign (author)temper2012-08-14

thanks for the information but i haven't heard of slip rings

pfred2 (author)agedesign2012-08-14

You haven't heard of slip rings because they basically suck so they're not used much. As others have pointed out the motor you started with is called a universal motor. It would have run on DC just fine without any modifications at all. The only common motors that are strictly AC are induction motors. They run because of current phase change.

Gordyh (author)pfred22012-08-16

Slip rings are not that bad. Every time you drive your car or truck, ect you are using them. They are built in to the alternator, and I have seen them last for 280K miles and more.

temper (author)agedesign2012-08-15

Oh slip rings are just two conductive rings around the motor shaft that the brushes rub against - they are wired to the rotor windings and pass the ac current through directly (i.e. as ac) rather than periodically switching the polarity around as a commutator does.

omnistructable (author)temper2012-08-15

You are right, all motors but an inductive motor will run on AC or DC. Look at the sign on the information tag, it must show AC / DC

pfred2 (author)rimar20002012-08-14

Put enough batteries together in series and you'll have the voltage. Although today the more practical solution is to use a phase inverter.

seljer (author)2012-08-16

If it was a universal motor you could probably also have rewired it to be a self excited generator. Or just applied a DC current to the stator coil to generate the magnetic field and used it as a DC generator.

scraptopower (author)2012-08-15

Whilst to the conversion from AC to DC wasn't needed, the motor will now make a reasonable little generator! Try spinning it and see how much power you get out. It will probably work at quite low speeds.

Thanks for posting,

fozzy13 (author)2012-08-14

This is a cool project! And something I've considered doing before.

However, as others have pointed out, your terminology is wrong.  Judging from the stator you have pictured, it seems that you took it from universal motor, meaning it will run without modification on AC or DC. A pure AC motor looks far different than a universal or DC motor, and is also called an induction motor.

Cool idea nonetheless : )

About This Instructable




More by agedesign:spud gunwater separatorhow to make a strong genorator
Add instructable to: