Abstract: A core machine is arranged to automatically refine the shape of a sand core upon removal of the core from the machine. The core machine uses a core box to form a core. After formation of the core and separation of the core box halves a shaping member is moved into a space between the core box halves. As the core is ejected from the core box and removed from the machine it passes through the shaping member which refines the shape of the core. The machine may also be used for dimensional tolerancing about the parting line of the core box.

Abstract: A crankshaft and counterweights are balanced by adding additional weight without modifying their outer dimensions. Bores are drilled into the counterweights and then a slug of material which is of a different density than the original counterweight material is inserted into the drilled bore. The slug may be held in place by any suitable mechanism, e.g., press-fitting, upset fitting, welding or threading. Particularly with threading, a slug shorter than the bore may be positioned anywhere within the bore.

Abstract: A core assembly is formed by molding a destructible plastic form in abutting relation to a rigid bonded core. The core assembly can be used for casting large or long and thin castings. The rigid bonded core reinforces the plastic form against flexural and torsional forces as well as forces within the plastic tending to change the dimensional configuration of the plastic form.

Abstract: A core assembly is formed by molding a destructible plastic form around at least one insert and optionally around a non-destructible core. The core assembly can be used, for example, for casting engine cylinder heads having valve seat inserts integral therewith. The plastic form retains and supports the inserts until the precise time the plastic is replaced by the molten metal.

Abstract: A core assembly for use in the casting of molten metal is formed by fabricating a first core, molding a plastic layer around the first core, and molding a second core around the plastic layer. The plastic layer is interlocked with an irregular outer surface of the first core, and the second core is interlocked with an irregular outer surface of the plastic layer. The plastic layer is then dissolved with a suitable solvent prior to placing the core assembly into a mold and molten iron being poured.

Abstract: A core assembly is formed by fabricating a first core, molding a destructible plastic layer around the first core, and molding a second core around the plastic layer. The plastic layer is interlocked wth an irregular outer surface of the first core, and the second core is interlocked with an irregular outer surface of the plastic layer. The core assembly can be used for casting engine cylinder heads to eliminate the need for gluing cores together and the accompanying formation of fins within fluid conducting passages.

Abstract: A core assembly is formed by fabricating a first core, molding a destructible plastic layer around the first core, and molding a second core around the plastic layer. The plastic layer is interlocked .[.wth.]. .Iadd.with .Iaddend.an irregular outer surface of the first core, and the second core is interlocked with an irregular outer surface of the plastic layer. The core assembly can be used for casting engine cylinder heads to eliminate the need for gluing cores together and the accompanying formation of fins within fluid conducting passages.