초록 ▼

A method of molding roofing shingles includes the steps of providing a compression mold having two mold bodies, and installing a mold insert in each of the two mold bodies. The surfaces of the inserts are shaped to correspond with the desired shape of a roofing shingle. A multiplicity of roofing shi

A method of molding roofing shingles includes the steps of providing a compression mold having two mold bodies, and installing a mold insert in each of the two mold bodies. The surfaces of the inserts are shaped to correspond with the desired shape of a roofing shingle. A multiplicity of roofing shingles are molded using the compression mold. Each molding step includes charging the mold with a moldable material containing resin in an amount within the range of from about 10 to about 40 percent, and filler material in an amount within the range of from about 60 to about 90 percent, wherein the filler material subjects the inserts to wear by abrasion. The inserts in the mold are replaced when they are worn out, but this is done without replacing the mold bodies.

대표청구항 ▼

[ What is claimed is:] [1.]1. A method of molding roofing shingles, comprising the steps of:providing a mold having two mold bodies;installing a respective mold insert into each of the two mold bodies, the mold inserts each having a surface shaped to correspond with a respective desired shape of a r

[ What is claimed is:] [1.]1. A method of molding roofing shingles, comprising the steps of:providing a mold having two mold bodies;installing a respective mold insert into each of the two mold bodies, the mold inserts each having a surface shaped to correspond with a respective desired shape of a roofing shingle;molding a multiplicity of roofing shingles using the mold, wherein the step of molding each of the multiplicity of roofing shingles includes charging the mold with a moldable material containing resin in an amount within the range of from about 10 to about 40 percent, and filler material in an amount within the range of from about 60 to about 90 percent, and wherein the filler material subjects the inserts to wear by abrasion; andreplacing the inserts in the mold upon wearing of the inserts, without replacing the mold bodies.