Question why do you want to know the RPM of your Headstock

[Ed in Tampa]

I have no issue with any one wanting to know the exact speed to set the dial but the tool / blades and or bits will let you know its boundaries and limits pretty quick . if the tools / blades and bits are not sharp the speed setting is out the window when it comes to quality . jmo

Even with sharp blades, if the speed is not appropriate for a particular operation the quality of the cut will be effected.

Ed in Tampa says he doesn't care. So be it. I care. That does not mean I tach every setting. I test my machine rpm periodically (against the dial setting) and I trust the speed control after doing so.

Thank you Dusty you make my point, the staring machine speed means little if the blade is dull or the wood particularly dense, that is when our other senses must kick in. I really do not care what the actual RPM of the machine is if it is producing the results I want. I agree RPM can be a diagnostic tool but something else will usually make you aware of a problem long before you need to check RPM. I cite professional racing, the drivers rarely know the exact RPM of the engine, what they focus on is the shift light, pit speed RPM, or if speed drops off is the RPM following suit or not. They focus on RPM when they want to know if a change has effected the engine or not. But their overall concern is, is the package producing the result they were after or not, which is usually lap time. That is my focus is my Shopsmith performing the task I want it to or not.