choice apertures 54 a provide alignment holes for alignment pins fig5 b shows a similar mold block configuration for the bottom half of mold 52 b however in the arrangement of fig5 b mold block 52 b comprises a split mold block mold block 52 b is split along line 56 b with bottom portion 59 b being removable as shown block line 56 b rises in the mid section in the area of the apertures 53 b to reduce and define the depth of the aperture array in the upper portion 50 b of block 52 b in this regard the aperture or cavity walls of apertures 53 b may be vertical or tapered fig3 a u2013 c show tapered walls it is clear that whichever wall configuration is used the aperture wall configuration would be the same in both the top half mold block 52 a in fig5 a and bottom half mold block 52 b in fig5 b it should be understood that bottom portion 59 b of mold block 52 b is removable to facilitate removal of the cast part thus with removal of bottom portion 59 b of mold block 52 b the cast part may be pushed out without damage after removal of the cast part from mold.