Scribing should be done at a clean and well-lighted place. The support must be flat and big enough to permit storing of the workpiece and accessories and scribing without hindrance.
Surface plate
Figure 10 Surface plate
Flat, usually planed cast-steel plate or granite plate used as support for scribing work, preferably with height gauges.
Note: Surface plates must not be damaged by hammering, chipping or straightening of workpieces.
Angle plate:
Steel angle with flat base and vertical locating face provided with T-slots for clamping of parts by means of locking screws (particularly of parts which dont have datum faces or edges).
Figure 11 Angle plate
Big steel-parallels
Equally flat testing tools of different sizes used here as support for flat workpieces for scribing with height gauges.
Figure 12 Steel parallels
Vees
Supports for cylindrical workpieces to prevent them from slipping or rolling away.
Figure 13 Vees
Stencils
Figure 14 Stencils
Accessories for scribing and prick-punching of larger batches or intricate shapes which eliminate the need for measuring the workpieces shape. Prick-punching is made by means of the stencil punch applied through hardened bushings. Further accessories are measuring and testing tools the design of which permits the scriber to be located and guided, such as: steel gauge, steel straight edge, try square.
T-square and centre square
Special squares for locating cylindrical workpieces to permit scribing of centres or lines on end faces.
Figure 15 Use of the T-square
Figure 16 Use of the centre square
Scratch gauges
Adjustable stops permitting the scriber to be guided along flat datum edges or faces. The size is set by means of a steel gauge.
Figure 17 Setting of the scratch
gauge
Which requirements must be met by the scribing place?
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What makes the difference between the use of centre squares and try squares?
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