. American foundry practice . nt with the i)lain ones were cast inloam, and, having worked on both jobs, I will give a de-scription of liow these were made when I get to loam making the plain pipes there was a sheet-iron curb sunkinto the floor to prevent straining, and to save work in dig-ging and ramming. The draw pattern was made of wood,and was 18 deep, witli four strong draw irons on it. Instarting to mould it, a cast iron ring, XX, is set level, fromwhich a level bed is made. Tliis ring is never disturbed, sothat the leveling by straight edges every time a casting is,made is avoi
. American foundry practice . nt with the i)lain ones were cast inloam, and, having worked on both jobs, I will give a de-scription of liow these were made when I get to loam making the plain pipes there was a sheet-iron curb sunkinto the floor to prevent straining, and to save work in dig-ging and ramming. The draw pattern was made of wood,and was 18 deep, witli four strong draw irons on it. Instarting to mould it, a cast iron ring, XX, is set level, fromwhich a level bed is made. Tliis ring is never disturbed, sothat the leveling by straight edges every time a casting is,made is avoided. When tlie bed is finished, the draw pat-tern is set down, and cores having the bottom flange formedin them, as shown at A, A, are set around the are two of these cores that the runner cores areattached to, as shown at B. These were set a quarter of acircle apart, and when all the cores were set, any open jointswere packed with hemp, so as to keei3 dust or dirt from get- CASTING LARGE PIPES IN GREEN SAND. 79. 80 GREEK SAKD MOULDING. ting to the flange. The facing and sand was shoveled in andrammed solid up to the level of the pattern, and then wellvented. When all was ready, a man was placed at eachscrew-handle. The cut only shows two screws and onebeam ; but as there are four draw irons needed, it takes fourscrews and two beams. At the word * Around ! each manturns his handle around once, doing this at every this way the pattern is drawn even. This is a splendidrigging for drawing gears or anything that needs to be drawnlevel and steady. This pattern was drawn about five inchesat a time, until it was raised up level witli the top of thecurb, which made it the height required. Tlie pattern wasleveled at every drawing, and the vents carried up to the topby venting at every raising. After the cope was rammed upand taken off, the segment D was bedded all around thepattern to form the top flange. The upright runners wererammed up in the green sand, and
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