Saw this on Ebay and thought it was worth a separate thread for anyone wanting a tacho on their lathe/mill.
This one's different as the sensor is included in the kit.
http://www.ebay.com.au/itm/Hall-Prox...item3a88a3221a
Many of use have already added these displays to equipment and they work well and are very handy, using a variety of sensors, and have created plenty of discussion on which of those is best :)
Cheers
Rob