Angle Plates & Try Square

Angle Plates

Are precision tools made of cast iron, tool steel, or granite (Fig. 2.13). They are widely used as fixture for holding work to be laid out, machined, or inspected. The faces are at right angles and may have threaded holes, slots, and fitted clamps for holding workpieces. Tool-makers’s clamps and C clamps are also used to hold the work. Angle plates are generally used on surface plates and machine tool tables. Cast iron plates are surface ground and hand scraped to a high degree of accuracy. Hardened tool-steel angle plates are surface-ground very accurately and may be lapped for accuracy and finish.

Try Square

It is better known as engineer's try square and is a very common tool used for scribing straight lines at right angles to a true surface or testing the trueness of mutually normal surfaces. They are made in different sizes out of steel pieces. In construction they are similar to a carpenter's try square but are comparatively more accurate. They can be made either in one piece or in two pieces. The most commonly used type is the one shown in Fig. 2.14. It consists of a steel blade fitted into a steel stock of rectangular cross-section.

They are well hardened and tempered to suit the need. Some more accurate types of try squares are made with their blades having bevelled edges properly ground and finished square. Both inner and outer surface of the blade are kept truly at right angles to the corresponding surfaces of the stock. In order to maintain this trueness this tool should be handled with sufficient care and should never be used as a striking or supporting tool. The accuracy of this tool should be frequently checked to ensure the trueness as it effects the accuracy of the finished job to a considerable extent.