The Pattern Maker's Handybook; A Practical Manual on Patterns for Founders Embracing Information on the Tools, Materials and Appliances Employed in Their Construction

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1887 Excerpt: ...The print as used in Fig. 77 is also applied in this case to ensure uprightness in the core. In addition to this a print cut to the form of the aperture required, is applied to the end of the bearing, forming an additional guide for the core. This is the method ordinarily followed, but if the exigencies of the work demand it, we may omit either one of these prints. If the print only is retained, make it much thicker, or the core may not be securely placed. The core-box will be made as shown in plan, Fig. 78. In sections it resembles Figs. 75 and 76, but at one end it is longer as much as the thickness of the print. The prints for the bolt-cores cannot be put on as before, as they would lock the pattern in the sand. The prints to be Fig. 78. Core-box. employed will not only cover the outline of the holes, but will be carried up to the parting line of the mould as seen in Fig. 77. In this figure, the prints on both cheeks of the block are shown in full line, and also one of the prints on the base in dotted line. A core can be made that will fill the spaces left by the Core Box'g 8 Prmts an( have the holes in the castings in the core-box, shown in plan, Fig. 79. Fig. 80 being an end view of the same with one end of the box removed. The prints employed for the bolt-holes in this figure are called long prints; they should have plenty of taper, so that the core may be easily lowered into its place. Ordinary prints have very little taper, and the core-box is tapered to match. Another plan of making the pillow-block to mould sideways, though it cannot always be employed, is shown in Fig. 81. The pattern is made in halves, the parting line of the mould passing through the centres of the bolt-holes. The bearing prints and core-box are similar to Figs. 77 and 78, with...