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October, 1917 line of the latter, and in this way the same square stations will do for the two plans. Not having copied the sheer-plan, the body-plan is next copied full size as nearly as possibly to the sheer-plan. In some cases where the mold loft floor is smaller than it should be, two plans overlap. On a very small floor, the same base-line may as well serve for three plans, one of the square stations in the midship being taken as the mid- dle line of the body-plan. Copying the Body Plan The body-plan is copied or drawn on the floor by measuring the distances along the several water and diagonal lines from the middle line to where they cut the square stations, setting these distances off to full size on the corresponding lines on the floor. Bat- tens are then penned or bent as in Fig. 47 so as to approximate as closely to these points as is consistent with ab- solute fairness or continuity. The lines then are marked in, usually with thin slices of chalk. At some yards _ it is customary to measure the ordinates, etc., and‘record them on paper in tabu- lated form before proceeding to draw the body full size on the floor. In this case, the latter operation is performed without direct reference to the drawing when working on the floor. The half-breadth plan is next to be drawn on the floor and here we again note that the lines which are curved in the body plan are straight in the half- breadth plan and vice versa. Having already drawn ‘the middle line of the half-breadth plan on the floor and the projections of the square stations in that plan, we proceed to copy the level or water lines from the body plan into the half-breadth plan. For this purpose straightedged battens are set to the middle lines of the body and half-breadth plans on the drawings. Now measure on a staff whose end is kept against the batten set to the middle line of the body-plan, the distance from this line to where a level line cuts each square station or frame station in the body-plan. Transfer these distances to the. corresponding square stations in the half-breadth plan on the floor by setting the end of the staff against the middle- line batten of that p'an, marking the distances out from the respective square stations. A batten: is then bent so it can pass fairly through as many as possible of these points, thus trans- ferring the water lines to the half- breadth plan. The diagonal lines and bow and but- tock lines from the sheer-draft are also transferred full size to the mold loft floor in much the same manner as just described. In fact, this process of transferring the lines to the floor is THE MARINE REVIEW comparatively simple if the principles of projection which underlie all draft- ing work are thoroughly understood. To be completely successful, the mold loft man also should have a_ good knowledge of descriptive geometry, which covers the details of the science of projection. As the various plans are copied on the floor it is found that there are discrepancies, as previously pointed out. These must be corrected by mutual ad- justment until the three plans coincide accurately. When discrepancies occur, the water and diagonal lines in the neighborhood must be examined to see if the points within the section were correctly taken, and if a modification of these lines, consistent with fairness, will give such points as the batten will spring to. The bow and buttock lines are a great help to both the designer and the drafts- man -in judging the character of the surface at the extremities of ‘the ship. No rules, however, can be laid down for guidance in dealing with them, ex- perience being required in order that they may afford a vivid conception of the form of the vessel. In practically performing all of the operations connected with laying down the lines on the mold loft floor, a great deal must be left to the judgment of the man in charge. A practiced eye will save much labor. When a batten does not spring well to the point, it is bent to pass outside some and inside others. As a rule the batten should pass on the outside more frequently than on the inside of the points in order that the volume of the ship may not be less than that given by the design. In copying and drawing the body-plan, it is advisable to draw the midship sec- tion first and then the others in rotation as the draftsman is thus better enabled to see what he is doing and exercise his judgment. Time Required for Framing Mold loft floors usually are painted. Generally a gray color is chosen. When a new set of lines is to be laid down. it usually is advisable to repaint the floor in order to completely obliterate all of the old lines. In some cases, however, the floors are not painted, but are left in a natural color. In these yards when new lines are to be laid down. the whole floor is gone over with a cabinet scraper, thus removing the old drawing. The finished molds are similar tc those shown on the pile of timber in Fig. 59. White pine, cedar, or other easily worked strips are used for making molds. ; As soon as the molds are .ready, the ship actually process of framing the may be begun. This process may be divided into three steps as _ follows: 375 Sawing the frame sections; assembling the sections, or buttocks; and raising the frame. The time required to frame a_ ship seems to vary widely in different yards. In one case the writer has been in- formed that 46 days were required to frame a 250-foot, 4-masted © schooner. In this yard the frames were skidded into position and raised by tackle, no cranes being available. In another yard only 15 days were required to frame the square body of a 290-foot ship, using the same method of raising the frames. To this should be added 10 days for the forward and stern cant frames. A gang of about eight to 10 men is required, not including those working on the framing stage where a dozen more are necessary. After the main frames are up the smaller pieces of the stern frame, including the tran- som, etc., can be framed with a gang of four or five men. Specifications of Timber Needed The frames of modern wooden ves- sels are sawed from timbers similar to those shown in Fig. 59. The sizes of timbers necessary and the quantity re- quired for framing a 300-foot vessel are indicated by the following quotation from the timber schedule for standard Pacific coast type wooden steamship, de- signed by Mr. Ferris for the United States Emergency Fleet Corp. The standard government boat, it will be recalled is 281 feet 6 inches in length overall and 46 feet beam. It has a cargo capacity of about 3500 tons on a draft of 23% feet. The frame timber specifications are as follows: Net Gross No. of Feet size size Length pieces B. M. 12x32 12% x 32 10 100 32,667 12 x 30 12% x 30 10 16 4,900 12 x 30 12% x 30 10 100 30,625 12 x 30 12% x 30 16 12 5,880 12 x 30 12% x 30 20 16 9,800 12 x 30 12% x 30 24 12 8,820 12 x 28 12% x 28 12 16 5,488 12 x 28 12% x 28 16 50 22,867 12 x 28 12% x 28 16 56 25,611 12 x 26 12% x 26 10 100 26.541 12 x 26 12% x 26 16 56 23,781 12 x 26 121% x 26 16 50 215233 12 x 26 12% x 26 28 20 14,863 12 x 26 12% x 26 28 16 11,891 12 x 26 12% x 26 30 80 63,700 12 x 24 12% x 24 16 56 21,952 12 x 24 12% x 24 16 50 19,600 12 x 24 12% x 24 16* 5 2,940 12 x 20 12% x 20 12 50 12,250 12 x 20 12% x 20 16 56 18,293 12x 16 12% x 16 12 56 10.976 12 x 16 12% x 16 12 50 9,800 12 x 16 12% x16 14 80 18,293 12 12 12% x12 16 0 15,680 10 x 24 10% x 24 16* 5 2,400 *And up, average 24 feet. It also may be interesting to note that the timber required for frames Nos. 35 to 60 in the 5-masted motor- schooner, the details of which were presented in Figs. 36 and 44, in the chapter published in the September is- sue of THE MARINE REVIEW, are as follows: T3eplecesse. o. oa eee 12 x 28 — 40 TS TieCES Sc Skee ee 12 x 20 — 30 39 MieGeS Le. fea ee 12 x 26 — 32