Review on Groz 1142 Graduated Workshop Square by Maurice Vianes

I used this to set up my miter saw, 90 degree bevel angles and adjusted the fence to be perpendicular to the saw blade. I've also used it to fix inexpensive combo squares to make them accurate. for woodworking (they weren't exact when bought). I filed the bearing surface for the slide ruler with a thin file until the combination square was accurate with this constructed square. They were then accurate when checked with a regular pencil test on the machined edge. I cleaned the square of grease and coated it with camellia oil to prevent rusting like I do with my chisels and planes.