MachTach Machine Tachometer

This Thing documents the MachTach machine tachometer which was a product I used to sell. I have stopped selling MachTach kits so I am now making the design open source so that people can make their own tachometers. Please read the documentation for information on how the MachTach works, how to assemble it, and how to select and use various sensors. The MachTach works with IR, Hall Effect, and gear tooth sensors. The gear tooth sensor is supported for gears with up to 90 teeth.

Here's an overvie