A low voltage 'magneto' ??

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10K Pete

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Ok guys, here I go again.:hDe:

I'm thinking about how to supply the proper electrons to the ignitor on my
future hit 'n miss. I've read a ton of stuff about low tension coils and batteries, battery savers, etc., etc...... I'd like to get rid of the battery.
But I want to stay with the ignitor!

This may be a bit of a dream, but bear with me please. I'd like to come up
with a small, hopefully sorta scale sized, generator that would provide two
things:

1) The low voltage (6-12) needed for the ignitor and it's coil.
2) Have to coil in the generator be the coil for the ignitor. ie: have enough
inductance to provide the kick for the spark.

I visualize a rotor with a high power neodinium magnet rotating in the
open end of a laminated iron armature 'U' shape with the winding on the
bottom of the 'U' shape. Now I know that this is a pretty standard configuration
for many synchronus motors and 'magnetos' but I haven't yet found an
existing unit that would provide the 6-12 volts and also has the wire size
(I'm seeing 18-20 ga. mentioned a lot) necessary to carry the spark current.

So I'm wondering if'n I'll have to build my own little generator.

The idea would be to have it driven off the cam gear with a small pinion
to get the speed up. I realize that the engine will have to be spun up to
operating speed to get juice but on a small engine that shouldn't be a
problem. Crank handle on flywheel??

Am I hunting a blue elephant here???

*discussion*

Thanks,
Pete
 
Start on battery power (9v battery) and switch to generator power when running and up to speed.
 
Hi Pete. Not sure if this is what you're after but small stepper motors make nice little generators when turned at low rpm
 
Hi Pete. Not sure if this is what you're after but small stepper motors make nice little generators when turned at low rpm

Really! I never woulda' thunk it. Do you have any ballpark numbers for
how much output at what speeds? I'm going to have to look into this...

Thanks!

Pete
 
Hi, Pete
Here is a gentleman that I have talked with at NAMES .
He has been working on miniature magnets for a few years.
He has made castings of scaled down magnetos similar to to the International hit& miss engines. He uses rare earth magnets and these are rotary mags. He is in Wyoming. I am sure that you will be able to learn quit a lot from him.
Good Luck! Let us know what you find out. You will be very impressed by him.

John Vietti [email protected]
 
Hi Pete. The output you get depends on the stepper you got. Most of the steppers use Neo magnets I think. The motors range in size from one the size of a small coin to quite beefy ones. Best thing is that they are cheap and easy to come by
 
Hi, Pete
Here is a gentleman that I have talked with at NAMES .
He has been working on miniature magnets for a few years.
He has made castings of scaled down magnetos similar to to the International hit& miss engines. He uses rare earth magnets and these are rotary mags. He is in Wyoming. I am sure that you will be able to learn quit a lot from him.
Good Luck! Let us know what you find out. You will be very impressed by him.

John Vietti [email protected]

Thanks! I'll be getting in touch with him in the near future.

Pete
 
Pete

Have a look at Minimag to get some ideas of what is possible in small sizes.
http://minimagneto.co.uk/Home.php

Dave
The Emerald Isle

Thanks Dave,

I've looked at Minimag but wasn't able to find a low tension magneto/
generator. Now I will go look again 'cause I easily could have missed
something but all I saw was their kit, including the 'export' version which
I though was really good thinking on their part. They have a nice coil
for use with a battery, but I'm looking for a magneto style where the
mag coil is also the spark coil. For use with an ignitor. I think you know
what I mean even though I didn't say it well. Been up all night...

Pete
 
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