Magnets

Looking for a link to a supplier of new magnets to replace the old Alnico's in a open frame motor. Roger Aultman

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On Tue, 8 Apr 2008 13:35:46 -0500, Roger Aultman wrote:

Ummm, considering the time involved in disassembling and reassmebling the motor, and the cost of the magnets, if such can be found, wouldn't it make more sense to find a can motor and adapt it, or even replace the entire gear train?
--
Steve

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Steve Caple wrote:

Also, the little fact that for the motor (end result) to function well, the "magnetization" needs to be done AFTER the motor is assembled.
[In other words, IF you have the capability of RE-Magnetizing the present motor, you can improve things to some extent by trading 'magnet slugs'. Otherwise, the present motor, when disassembled and reassembled with a different (better) Permanent Magnet Slug, will NOT be as good as where you started from. {Unless your present motor has been disassembled and re-assembled without benefit of getting re-magnetized.}]
Chuck D.
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It's not the answer to your specific question, but have you tried re-magnetizing the old magnets? Several years ago I saw a "kink" about making a remagnetizer for about $0.50. Find two old junked CRT type TV's and look for the choke coil that looks like a medium sized transformer but with just two wires coming out of it. Look for high current chokes, which will have about No. 24 wire in the coil. Disassemble the chokes. The laminations will have a shape like a squared-off "8"; one side is detachable (that's how they got the coil in there) and is only glued in place - a good tap with a hammer will convert the "8" into an "E" and an "I" with the coil still around the center post of the "E". Assemble these four choke parts with the "E"s facing each other, with space for your motor magnet (still assembled in the motor) between the center posts of the "E"s, and the two "I"s bridging the air gap between the outer posts of the "E"s to complete an efficient magnetic circuit. Wire the two coils in series with each other, making sure that the coils are connected so the magnetic fields add (the center pole of one "E" should be North when you bring a compass near it and the other center pole should be South) and add a 10 amp diode in series as well. Do this test with the 16 VAC accessory power from a power pack. Mark the poles of the "E"s N and S. When the polarity is correct, substitute a 120 VAC line cord, put in the motor with it's magnet matching the marked poles. Then plug it in for a few (about 5) seconds. The diode gives you half wave DC which reduces the effective AC voltage so you won't burn out the chokes in these brief power applications, but the high current produces a very strong and concentrated field to remagnetize the motor. Make sure it's all well insulated. It's Rube Goldberg, but cheap and it works. Geezer
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