When cores are made in core boxes and placed in the mold it becomes necessary to support them in such a manner that there can be no possible chance for a change of position during the time the mold is being filled with the hot metal. To give the core this support, special recesses are

Figs. 19 and 20. Pattern and Mold Showing Core Print.

made in the mold to receive them. These recesses are made by attaching pieces called Core Prints to the pattern, as shown at A and B Fig. 19. These core prints should be colored differently from the rest of the pattern, so that the molder may readily distinguish where the cores are to be placed. For our work we we will use orange shellac for core prints and the inside surface of core boxes.

As cores are always a source of more or less trouble to the molder, these prints should be made of such a shape and size as will give the least trouble to the molders. The core should exactly fill the recess left by the core print, and the core print should be made large enough so that the recess left in the sand will not be crushed out of shape by the weight of the core or the action of the molten metal. Large core prints for vertical cores should be tapered, go that the trouble of withdrawing the pattern from the sand may not be increased by their presence, and also that the core may be easily placed in the mold. Core prints leaving recesses for a horizontal core should have plenty of draft in each end to facilitate in drawing the pattern readily from the sand.

Fig. 20 shows a mold made by the patterns shown in Fig 19. The ends of the core C fit in the recesses left by the core prints, as shown at A and B.