Project: To build a simple model generator to help me get my head round the idea of electricity generation.
Note: THIS WAS NEVER BUILT TO PRODUCE USABLE POWER. BUT DEMONSTRATE HOW POWER IS PRODUCED.
Not so much of a how to but more a demonstration of materials that may give others ideas for their own projects.
This little model is made from
Tesco's best plastic chopping boards, it is very easy to cut drill and you can use self tapping screws The plastic has good self lubricating properties and allows axles to run smoothly with out the need for lubrication or bearings. Its one downside is that it has to be screwed together as noting seams to stick this stuff.
6mm and 8mm Aluminum rod from B&Q about £4 a per 1mtr length
coils from scavenged microwave oven fans. These where used because I happened to have them at the time and this saved me from winding my own coils.
self tapping screw nuts bolts etc.
Fun little project that is simple enough to build the plastic is easy to work and allows this to progress rapidly.
Note. the plastic shavings get everywhere so be warned best to hover up as you go along.
Thanks for looking.
Step 1: Its Like Building Your Own Lego Set
My idea was to make a set of parts that could be easily changed around into various different configurations.
I stated out by sawing 1 chopping board into strips on the table saw
1 piece 100mm wide form the base
the rest I cut into 50mm and 40mm strips these would be used for uprights etc.
The base was marked out and drilled with a uniform series of holes that would allow this little rig to easily to be altered at any time.
I used the hole saws in the pillar drill to make any of the circular parts.
I glue a paper template to the chopping board with spray mount. This had all the holes marked on and as long as i had the center drill of the hole saw on the right mark all the other holes would be spot on.
the center drill of the hole saw was something like 5mm so allowed me to drill the holes out to be either a sliding fit drilled 8.5mm or a tight push fit of 7.5mm for attaching to the axles.
A friend described this process as reminding him of playing with sickle bricks as it was is so easy to chop and change things as you tinker you invention to life.
Step 2: The Rotor and Magnets
I had bought 36 10mm x 10mm round bar magnets for experimentation purposes.
I planed to use 12 groups of 3 in the rotor.
I had to laminate 3 disks together to be able to take a group of 3 magnets and seeing how this stuff don't stick I used 6mm alu bar as dowels to hold the disks together.
The center hole was drilled out to 7.5mm and was i nice tight fit, it started slipping a bit due to the pull of the magnets but this was easy to solve by using a pair of pliers to make key the end of the alu bar which helps grip it tight.
The holes for the magnets are made to be a tight push fit. they are mounted so that they are alternately N S N S
Step 3: The Coils.
I scavenged the magnetron from a few broken microwaves at my local recycling depot. i pulled the fans out of them too as they looked like they had some fun potential.
I found 3 matching coils in the fan motors but one turned out to have a short in it
It attach them i drilled a 2.5mm hole through the laminated core and used the stems of pop rivets to nail them then to the plastic disk and the nails when ten clinched over, crude but effective.
By shear luck the coils are actually in phase with each other by default
I do plan to wind some proper coils to suit this little rig to see what it really can do. this will be a job for the winter months when I'm stuck indoors. I will eventually do this and will post any details of the outcome.
Step 4: Bridge Rectifier, Simpler Than It Sounds.
This is the main reason why i built this test rig was to get my head round the bridge rectifier.
I dropped physics at high school in flavor of art. so my knowledge of electronics is a bit basic.
A friend gave me the diodes need to make this one, I first drilled the 4 holes in the plastic and bent the legs of the resister so the fitted in the formation and the leg where soldered together to form the contact for the wires.
Step 5: Bridge Retifier
This pic shows the back of the bridge rectifier and how the legs of the diodes where soldered together.
Step 6: Wireing
I scavenged the wire from an old computer power supply unit.
i wrapped the wire round the blade of a screw driver to give it the coiled look, this helps keep the wires tidy and gives a more pleasing finish
I used dog clips on the wire coming out of the bridge rectifier colour coded to positive and negative.
Step 7: The Crank Handle, Keeping It Simple.
A 4mm bolt and a the barrel of a cheap biro. The biro is wrapped in a small piece of vinal tape as they tend to crack if you even look at them crooked.
About as simple as it gets.
Step 8: The Outcome - Pure Raw Power, Well Maybe.
1.21giga watts!..... well not quite. poor Marty must remain stuck in 1955 (forever avoiding his own mother... ahem)
The little rig produces up to about 20 volts if you crank it like mad.
Unfortunately its at micro amp level, just enough to light a led bulb.
Lets put it this way it works, and can help me demonstrate the production of electricity to those who make the mistake of asking me ;-)
Some day I will wind some small test coils that would suit this rig and see what it is truly capable of.
Well I hope you like my little show and tell, I hope that it gives some of you diy builders ideas for you own mini generators.
Thanks for looking.