charging magnets off flywheel

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Dennis_Brown
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charging magnets off flywheel

Post by Dennis_Brown » Sat Sep 21, 2019 10:55 pm

I know this has been covered somewhere before. I have a round aluminum plate given to me by an old T restorer years ago. It is drilled to allow you to mount magnets like on a flywheel. If I mount correctly oriented magnets to it can a mag coil ring be layed directly on it to try to charge the magnets or does the coil ring not have to touch the magnets.
Next how do you tell when they coil ring is in the correct location?
Can recharging this way be done using 12 volt or is higher voltage required?
The reason I am looking at doing it this way is a brass 14 -24 brass screw broke the small metal magnet retainer lodged between the ring gear and starter and the running motor stopped abruptly and inertia caused 9 magnets to break. I have quite a few spare magnets but will measure them for uniform thickness and they could use more strength.
If magnets are recharged individually with a home made wire wrapped charger do you also need more than 12 volts?
Thanks!


whedges
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Re: charging magnets off flywheel

Post by whedges » Sun Sep 22, 2019 8:58 am

I have recharged magnets with 6 volts with wire rapped about 20 turns 10 on each leg.

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Steve Jelf
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Re: charging magnets off flywheel

Post by Steve Jelf » Sun Sep 22, 2019 9:23 am

I've never used this method, but I don't think it matters if the coil ring touches the magnets. Try it and see what results you get. If your magnets won't hold a four pound weight, charge them individually with more batteries connected in series. I use 36 volts.

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CudaMan
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Re: charging magnets off flywheel

Post by CudaMan » Sun Sep 22, 2019 10:50 am

Mark Strange
Hillsboro, MO
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RajoRacer
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Re: charging magnets off flywheel

Post by RajoRacer » Sun Sep 22, 2019 11:11 am

Or, make one of these.
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mike zahorik
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Re: charging magnets off flywheel

Post by mike zahorik » Sun Sep 22, 2019 11:16 am

To efectively magnetize a piece of iron, you need to force as much magnetic flux thru it as possible and make an abrupt change in that flux. Magnetic flux is produced by ampere turns. This means high current thru a lot of turns in a coil. The other important item is to reduce the magnetic resistance of your magnetic circuit. Your magnetizer has to fit snugly to the ends of the Model T magnet, very little air gap between the two. But the process is relatively forgiving. If you do a search of the forum you will find many different approaches and they all seem to work. Testing the magnets will give you an idea of how good your magnetizer is. A charged magnet should easily pick up 3-4 pounds of iron. One additional point, closely inspect each one of your magnets for cracks. A cracked magnet will magnetize, maybe not fully, but could look good enough, yet may break once inside your engine causing a lot of damage. Anyway, here is what I use. Good Luck Mike
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Chaffins
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Re: charging magnets off flywheel

Post by Chaffins » Sun Sep 22, 2019 12:27 pm

Magnets should be charged after mounting them. Pounding on the magnets with a hammer to set magnet height tends to reduce the charge..

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Re: charging magnets off flywheel

Post by Steve Jelf » Sun Sep 22, 2019 3:41 pm

I dislike the notion of hammering magnets to adjust the height. I charge them off the flywheel for maximum effect, then mount them with shims to bring the low ones up to a uniform height. I call a height variation .002" or .003" a perfectly acceptable range within the recommended setting of .025" to .040". As Dude Lester says, it don't hurt the runnin' of it none.
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