sawmill alt--one last try---maybe : }

[hiker]

sence my sawmill alt selfdestructed on its first real life run--some time back..

i thought i might try a 3 phase set up-9 and 12..the mags are 4" long by 1" wide..

coils are 5 and 3/4" long---the copper colored coils are made from #15 wire i belive..

the green and red coils are made from 2 diffrent srands of wire..which equals to about #17 wire..sence im using ceramic mags for now i thought i might try some long legged coils to get the max out of the mags..55 turns per coil --not sure if thats enough or over some what..my single phase alt. needed 85 turns per coil for a low start up..

8 coils 8 mags..

this alt will be a dual 12" rotor setup--i might try and compress my coils down to 1/4"..

not sure if the stator would be strong enough for that--the coils will be inlaid in wood then epoxyed over..

heres a shot of the start........................

[electrondady1]

hiker,ive got a lot of old saw blades on the shelf so i'll be following this one closely.

 will you use a single saw blade for each magnet rotor or double them up?

ive tried to mount the disks on a single shaft with a spacer between but had difficulty getting them to run true.

using long mags and coils seems like a good idea to me.the  copper on the ends will be a smaller percentage of the whole coil.  

[DanB]

Neat project!

Id consider making the coils a bit more 'wedge' shaped so they're wider at the top, than the bottom.  Make the 'holes' perhaps slightly smaller, but hte same rough shape as the gaps between the magnets.  

It would be interesting if you could test a single coil like this vs one of the coils you have now, I expect you'd see improved output.

[hiker]

i have some 10" blades to mount on the back side of the 12" rotors and some big whashers on the inside--it should help out to keep it stable..these will be mounted on a 1" shaft--with two block bearings..

my old sawmill alt -worked fine with almost the same number of mags but in a block formation.

[hiker]

thanks dan..

the coils are flexable yet so i should be able to pull them apart somewhat..

i was thinking i might lose some voltage --sence the legs are so long they reach almost to the bottom of the rotors[low speed area]-but it should make up for that loss in a incress in amps[long legs]..

well its a start--kinda busy right now so this one might take awhile to knock out..

later..........

[richhagen]

Hi Hiker, I had tried to build one of these a while back as you recall, but was disappointed with the output of my design.  I will be following your project as well.  Good luck, Rich Hagen

[DanOpto]

Your outer end of the magnets will be travelling twice the speed as the inner end of the magnets because the inside end of the magnets are too close to the center.

Your electricity generation is created by the movement of the magnets over the coils.

Because your outer wire "sees" a much faster rate of change than the inner portion of the wire, you output will be reduced. The inner portion will not contribute very much to the output.

I suggest increasing the radius of your disc so the magnets only cover the outer 1/4 of the disc.

This will increase the speed of the magnets and increase your output substantually.

The cost of the magnets and wire are one of the higher cost areas of assembling a generator.

By increasing the size of the rotor, you will increase the output with a very little increase in cost.

I hope this helps.

[hiker]

thanks for all the feedback guys...

guess i will go with the tried and true design..

[electrondady1]

i will go with the tried and true design.

i'm very curious about the possible output of the layout you have depicted hiker. hope you finish it and do some testing.

i think utilizing/recycling the old saw blades is a cool move.

making the mags/coils really long is also some thing i keep thinking about.

if you don't do it , at some point i guess i'll have to!

good luck   shawn

[hiker]

to late shawn--

i rewired the coils--played with my mags-[stacked veruses-side by side]

side by side i get more volts--stacked less volts but more amps..

both tests were done using the same size coils...

will make a new post --with all the results--kinda like 3 phase[turns a whole lot easyer when under load]-after the demize of my 8 coil alt single phase..the single phase alt did have a lower start up speed -plus more volts-less amps i belive..-----im still thinkin about those long legs[must have somthing to do with human nature]..just a matter of time!!