Making an angle plate
Having made two cylindrical squares it is possible to make an angle plate from a casting. On a vertical milling machine it is only practical to mill a large flat surface if it is parallel to the milling table.
An angle plate needs two flat surfaces at right angles to each other. To start with there are two rough surfaces. The first surface is cleaned up with a file so it will sit flat on the cylindrical squares. This surface is clamped to the cylindrical squares. The second surface, which is now horizontal, is machined so it is flat. The angle plate is removed from the cylindrical squares. The flat surface is now clamped to the cylindrical squares. The top surface is now machined. This surface will, by definition, be at right angles to the other surface. The result is two flat surfaces at right angles to each other – an angle plate.
Fig. Using cylindrical squares to hold an angle plate casting 553
Fig. Finished angle plate 563