MTFCA Forum

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

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

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

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.

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

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.

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

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.

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?

I just happened to have a spare set of magnet clamps like the "C" pictured so I did a quick voltage test with the stock flywheel and the "A" clamps and then changed just the clamps and retested with the Franken-Tester using the same magneto and magnets. The "A" clamps outperformed the "C" at all three tested speeds. At 500 rpm the test results were 10.6 volts vs. 10.2 volts. At 1000 rpm the results were 20.35 volts vs. 19.76 volts. At 1500 rpm the results were 29.35 volts vs. 27.9 volts. Another revelation was that the older style clamps were much more prone to bending, making the alignment more difficult and at the same time were more difficult to position since the alignment lugs were on the outside of the magnets rather than just on the space between them. Nothing to gain by using the earlier clamps, apparently.