Hi Seth, If you google "555 timer" you'll get lots of info on capacitor and resistor values and pinouts on the timers.

Here's a link with a bunch of different schematics to make the timer do different things:

http://home.cogeco.ca/~rpaisley4/LM555.html#22

If you scroll down the page to the part about missing pulse detector, you'll find several different ways to accomplish a shaft monitor function.

The timers are cheap and very versatile, the different uses are only limited by your imagination.