[Shop-talk] Tachometers

[Randall]

Has anyone tried either the contact
http://goo.gl/BZ98H
 or non-contact tachometers from HF?
http://goo.gl/usd3Q

I'd like to map out the various spindle speeds for my 10" lathe, vertical
mill & drill press; plus I occasionally want to know how fast some other
shaft is turning.  For example, at the moment, I'm trying to repair an old
speedometer and it would be a lot easier to test if I could spin it with a
drill motor and know what it should be reading rather than having to install
it in the car and take a drive.

-- Randall