On 05/01/2014 11:12 AM, Tim Wescott wrote:
Problem statement:

Mount a small (nominally 3.2 x 1.6mm) NdFeB magnet in an aluminum model
airplane spinner backplate (for a tachometer).


Tear apart an old computer hard drive. There is a supermagnet in there
(apparently) epoxied to a steel backing plate.

The magnet is brittle, you should be able to get a size small enough to
fit the spinner but strong enough to trigger your sensor.

Perhaps mount two magnets, diametrically opposed on the spinner, and
a half divider circuit for the tach?



technomaNge
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