Granite Surface Plate – The Foundation of Metrology

In this episode, we want to recognize and appreciate a piece of measuring equipment that rarely get much glory but is the foundation for much of the work done in this business – the granite surface plate.

The surface plate is simply a big flat rock. Designed stiff and massive to not distort, nice and hard to limit wear, and flat, so we can use it as the reference in measurement. A typical measurement on a surface plate involves something like this height gage, where either the part or the gage moves around on the plate.