Page:Sheet Metal Drafting.djvu/52

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21. The Painter's Pail.—The Painter's Pail, Fig. 52, is generally made of No. 28 Black Iron. The bottom of the pail is double seamed but it is not soldered. The wire bail is formed with a hook on each end. These hooks are inserted in holes punched through the sides of the pail.

A full size elevation, using the dimensions given in Fig. 53, should first be drawn and dimensioned. The lines representing the wire at the top of the pail should be slightly more than ⅛ in. apart. Two lines at the bottom represent the double seam and should be in. apart. The upper left-hand corner of the elevation should be "broken" in order to determine accurately the profile of the "hook" on the end of the bail. Extension lines drawn downward from the elevation locate the profile, Fig. 56. The horizontal center line of the profile should be drawn at a distance of three inches from the elevation. By means of the "T-square" and triangle a vertical center line of the profile is put in. The profile is then completed. The center lines will indicate four points on the circumference. These points are to be numbered 1, 5, 9, and 13 as shown. In order to divide the circumference into sixteen equal parts, as indicated, the student should proceed as follows:

With points 1 and 5 as centers, draw two arcs that cross each other as at A. You may use any radius in drawing these arcs. Carefully connect point A with the center of the profile by a straight line. This line will divide that part of the profile between points 1 and 5 into two equal parts. Number this center point 3. With points 1 and 3 as centers repeat this operation, thereby obtaining point 2. The space between points 1 and 2 may be used to divide the profile into sixteen equal parts.

The straight line from point A to the center of the profile also divides the angle formed by the horizontal and vertical center lines into two equal parts. The angles shown in Fig. 54 are to be bisected. Since these angles have no arc shown, it will be necessary to draw one. The corner (vertex) of the angle should be used as a center. The radius should be as large as possible and yet have the arc cut the sides of the angle. This arc will give