Practical Miter Cutting

shown, line, plan, draw, lines, miter-line and elevation

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We will not go into any further demonstration about this

curved work, as the matter will be taken up at its proper time later on.

'1'o obtain the pattern for the upper and lower return mouldings, proceed in precisely the same manner as explained in connection with returns 13 a:!(1 I) in Fig. 303.

Ln Fig.

306 are shown the plan and elevation of a gable moulding 'n octagon plan. 'Phis problem should be carefully followed, as it presents an interesting study in projections; and the principles used in solving this are also applicable to other problems, no matter what angle or pitch the gable has. By referring to the plan, it will be seen that the moulding has an octagon angle in plan a b c, while similar points in elevation a' b' c' run on a rake in one line, the top and foot of the moulding butting against the brick piers B and A.

The method of proceeding with work of this kind is explained in detail in Fig 307, where the principles are thoroughly explained. Let AB C D E represent a plan view of the wall, over which a gable moulding is to be placed, as shown by G H I J, the given profile of the moulding being shown by L M. Divide the profile into equal spaces as shown by the figures 1 to 4. Parallel to I H or J G, and through the figures mentioned, draw lines indefinitely as shown. Bisect the angle B C D in plan, and obtain the miter-line as follows: With C as center, and any radius, describe the arc N 0. With N and 0 as centers, and any radius greater than C N or C 0, describe arcs intersecting each other at P. From the point C, and through the intersection P, draw the miter-line C Q. Transfer the profile L M in elevation to the posi tion shown by R S in plan, dividing it into the same number of spaces as L M. Through the figures in the profile'R S, and parallel to D C, draw lines intersecting the miter-line C Q, as shown. From the inter sections on the miter-line, and parallel to C B, draw lines intersecting the surface B A. Now, at right angles to C D in plan, and from the intersections on the miter-line C Q, draw vertical lines upward, inter secting lines of similar numbers drawn from points in profile L M in elevation parallel to J G. A line traced through points thus obtained, as shown from 1' to 8', will be the miter-line in elevation.

For the pattern for that part of the moulding shown by C D E Q' in plan, and 11 G 8' 1' in elevation, proceed as follows: At right angles to 1 H in elevation, draw the line T U, upon which place the stretchout of the profile L M, as shown by the figures 1 to 8. At right angles to TL', and through these figures, draw lines, as shown, which intersect with lines of similar numbers drawn at right angles to 1 H from intersections on the miter-line 1' 8' and from intersections against the vertical surface H G. Lines traced through points thus obtained, as shown by V VV X Y, will be the pattern for that part of the gable shown in plan by C D E Q' of Fig. 307.

In Fig. 308, on the other hand, the position of the plan is changed, so as to bring the line A Q horizontal. At right angles to B C draw the vertical line C E, on which locate any point, as E. In the same manner, at right angles to C B, draw the vertical line B J indefinitely. From the point E, parallel to B C, draw the line E 8", intersecting the line J B, as shown. Now take the distance from 8" to J in eleva tion, Fig. 307, and set it off from 8" toward J in Fig. 308. Draw a line from J to E, which will represent the true rake for this portion of the moulding. Now take the various heights shown from 1 to 8 on the line Z Z in elevation in Fig. 307, and place them as shown by Z Z in elevation, Fig 308, being careful to place the point 8 of the line Z Z on the line 8" E extended. At right angles to Z Z, and from points on same, draw lines, which intersect with lines drawn at right angles to B C from intersec tions of similar numbers on C Q in plan. A line traced through points thus obtained, as shown by D E in tion, will be the miter-line on C Q in plan.

From the intersections on the miter-line D E, and parallel to E J, draw lines, which intersect with lines drawn from intersections of similar numbers on A B in plan at right angles to B C. A line traced through points thus obtained, as shown by F J, will be the miter-line or line of joint against the pier shown in plan by B A.

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