Built from a dirt-floor garage in Marion, Ohio, J-Lenco has produced sand cores for ferrous and non-ferrous foundries since 1968. The family-owned and operated company now makes cold-box cores for prototype through high-volume work, including a former run of roughly 20,000 rotor cores per day for Kelsey-Hayes. J-Lenco also produces ASTM-standard test cores and maintains traceable quality controls on each mix.
ASTM A395 specifications
Compliance program
ASTM A367 specifications
Compliance program
Founders Sand CoresWith more than 30 years of core-making experience, Founders Sand Cores produces sand cores for foundries, from established production work to complex new designs. The Deerfield, Ohio shop is notable for pairing traditional cold- and hot-box work with 3D-printed sand cores, a capability it began developing in 2024. Founders also researches 3D-printed foundry tooling and sand reclamation as it helps customers move prototypes and difficult castings toward production.DEERFIELD, OH
Kore MartSince 1981, Kore Mart has supplied foundries with custom cores, resin-coated sand and related production services. Based in Hamburg, Pennsylvania, the company also operates what it describes as the country’s only sand-recycling service, processing used foundry sand for reuse. Kore Mart has added 3D-printed sand cores and molds with an ExOne S-Max printer while continuing to support foundries with in-house technical expertise and logistics.HAMBURG, PA
TH Manufacturing IncTH Manufacturing grew out of a small Holmes County foundry founded in 1975 and reopened by two foundry engineers in 1992. Now rooted in Ohio’s Amish country, the company is known for its experienced Amish core makers and for solving unusual foundry problems through molded sand cores and custom-built equipment. It has completed more than 9,000 unique projects for foundries across the United States and beyond.MILLERSBURG, OH
Epcor FoundryFounded in 1946, Cincinnati-based Epcor Foundry is a third-generation aluminum sand foundry producing complex, highly cored and leak-tight castings from prototype through production. As a division of Seilkop Industries, it combines in-house tooling, simulation and finishing with production foundry processes so prototypes reflect real manufacturing conditions. Epcor is certified to ISO 9001:2015 and IATF 16949:2016.CINCINNATI, OH