GB685857A - Improved method of preparing moulds for metal castings more particularly for air cooled cylinders - Google Patents

Abstract

685,857. Moulding processes; patterns. IDOSON MOTOR CYLINDER CO., Ltd., and TAPT., T. H. March 13, 1951 [March 14, 1950], No. 6323/50. Class 83 (i). In a method of making moulds, weak portions of the mould are strengthened or supported by low melting-point material in the metal ways and by wire inserted through such material so as to project into the main body portion and into the weak portions of the mould, and the mould is then dried at such a temperature that the low melting-point material melts and runs off. The invention is described in connection with making a mould for casting an air-cooled cylinder barrel with a cowling 6 extending round a part of the periphery of the cooling ribs 4, Fig. 2. A half pattern 10 of the barrel without the cowling portion 6 is placed on a base plate 11 and within a moulding box 12 and moulding sand s is poured in and rammed until the level extends to the ends of the ribs 4 as shown in Fig. 3. A destructible pattern 13 of the cowling made of wax or other low melting-point material is then placed in position across the ends of the ribs and pins or wires 14 are inserted through the pattern into the sand in the spaces 7 between the ribs 4. The rest of the moulding box is then filled as shown in Fig. 5. After drawing the pattern 10, the sand is dried in an oven and the pattern part 13 melted and run off.