Magnet Clamps

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ABoer
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Magnet Clamps

Post by ABoer » Mon Feb 02, 2026 10:41 am

Hi All ;
Can you tell me what are the best Magnet Clamps ?
Thank for your answer .
Toon
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George House
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Re: Magnet Clamps

Post by George House » Mon Feb 02, 2026 11:14 am

I think “the Best Magnet Clamps” would be the one compatible with your 16 magnets. I use your ‘A’ clamp for engines 1914-1926.
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speedytinc
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Re: Magnet Clamps

Post by speedytinc » Mon Feb 02, 2026 11:19 am

I think using the wider clamp (C) will give you a smaller dead spot between nodes.
A is the more common clamp. I see no advantage to B


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Re: Magnet Clamps

Post by TXGOAT2 » Mon Feb 02, 2026 11:28 am

According to a Ford Service Bulletin of January, 1924, recharging magnets in the car can only achieve about 60% of full strength. For full original magnet strength, the magnets have to be removed and individually recharged, or replaced with new ones.


Mike Silbert
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Re: Magnet Clamps

Post by Mike Silbert » Mon Feb 02, 2026 11:38 am

For me the best clamp is "A"
I have them, and they generate more than enough magneto power for my needs.

I have never noticed (or measured for) any real world performance difference in the types of clamps.
Unless I built the engine I don't even know what type is in there.

It would take a setup like The "Franken-Tester" to tell what realistic facts are.
viewtopic.php?f=2&t=51653
I am curious to know if there is a measurable difference.

Mike


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Re: Magnet Clamps

Post by Scott_Conger » Mon Feb 02, 2026 12:01 pm

Each magnet clamp was associated with a specific coil assembly design - each one being different. A team of engineers, each knowing far more about their design than I, decided at the time what that mag coil shape and magnet clamp shape should be.

Since the last magneto design (corresponding to part "A") was the most powerful magneto produced, I'd say they knew what they were doing.

If it was my rebuild, the choice of magnet clamps would be decided upon by the year of the car and the specific style of mag ring that it was going to be used with.
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Re: Magnet Clamps

Post by TXGOAT2 » Mon Feb 02, 2026 12:42 pm

Besides the shape, the composition of the steel may differ from one type to another.

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Re: Magnet Clamps

Post by A Whiteman » Mon Feb 02, 2026 1:51 pm

I'd say they knew what they were doing
given that lower cost was the goal their aim would be to reduce the manufacture cost even by 'shavings', hence A won out in the end.

Toon, I doubt you would notice much, if any, difference in performance between each design 'in the real world'.

All the best.


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Re: Magnet Clamps

Post by speedytinc » Mon Feb 02, 2026 2:17 pm

A was used for the highest output magneto(15) thru to the end. 15 had the double stack coils & the improved, taller magnets. Output was increased to power the new electric lights.
From this point changes were made to the field coils only, supposedly as cost savings measures. Next field coil iteration used a wide single stack, then to narrower stacks.(thinner coil stacks, less copper.)

Depends on your goal. Do you want to be 100% original to the year of the motor or do you want max output?

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