measurement from a scale to the work, set one pointof the dividers on the mark and carefully adjust theother leg to the required length, as shown in figure 2-5.To scribe a circle, or an arc, grasp the dividersbetween the fingers and the thumb, as shown in figure2-6. Place the point of one leg on the center, and swingthe arc. Exert enough pressure to hold the point oncenter, slightly inclining the dividers in the directionin which they are being rotated.TrammelPointsTo scribe a circle with a radius larger than yourdividers, you should select TRAMMEL POINTS. Themethod of adjusting the points, as shown in figure 2-7,is to set the left-hand point on one mark, slide theright-hand point to the required distance, and tightenthe thumbscrew. The arc, or circle, is then scribed inthe same manner as with the dividers.need a right angle for a layout. Breakout your dividers,a scriber, and a straightedge. Draw a base line like theone labeled AB in figure 2-8. Set the dividers for adistance greater than one-half AB; then, with A as acenter, scribe arcs like those labeled C and D. Next,without changing the setting of the dividers, use B asa center, and scribe another set of arcs at C and D.Draw a line through the points where the arcs intersectand you have erected perpendiculars to line AB,forming four 90-degree, or right, angles. You have alsobisected or divided line AB into two equal parts.Constructing a right angle at a given point with apair of dividers is a procedure you will find usefulwhen making layouts. Figure 2-9 shows the methodfor constructing a right angle at a given point.Constructing a 90-degree, or right, angle is notdifficult if you have a true, steel square. Suppose thatyou have no square or that your square is off and youFigure 2-7.—Setting trammel points.Figure 2-5.—Setting the dividersFigure 2-6.—Scribing an acr/circle with dividersFigure 2-8.—Constructing a 90-degree angle by bisecting aline.Figure 2-9.—Constructing a 90-degree angle at a given point2-3