Measuring and Marking Video

[jbasen]

When you do a 5 cut  calibration  on your  table saw sled  or slider  and the  final  off cut is  within .0001  of an inch  then  you could  calibrate  your squares from this?

I use the following process

1) Hold your square against the straight edge of a good sized piece of plywood, hardboard, workbench top, or other similar flat surface with a consistent straight edge.

2) Draw a line across the flat surface with your square

3) Flip the square so that the part of the square that was held along the edge of the surface is 180 degrees from its original position

4) Line the other part of the square up with the line that was drawn.

5) If there is any error in your square it will show as double the actual error.  So if your square has a 1 degree error, the difference between the line you drew and the square in the 180 degree flipped position will be 2 degrees.

This is a quick and easy test.  You can find lots of videos on the web demonstrating this if my instructions aren't clear