GIVEN ACQUAINTANCE with the principles involved, and the necessary time and care, hand fitting methods as applied to basic equipment such as faceplates, straightedges and squares, can attain the highest standards of precision. Contrary to what might be thought, the methods employed are for the most part extremely simple-and, moreover, have applications in optics, where the highest machine precision falls short of requirements.
In possession of a faceplate, straightedge (such as a good steel rule) and a square, it is possible to undertake various tests of work and components.
A part with a flat surface can be placed on a faceplate and tested for “rock” with the fingers. Lightly oiling the faceplate, or using a smear of red lead and oil mixed together or marking blue, the component when lifted…
