ACCU-MOLD LLC | Plastic Engineering and Tooling Accu-Mold is a plastic engineering and tooling company located in Portage, Michigan. For nearly 40 years, Accu-Mold has been successfully serving our customer’s tooling and molded part needs. Their st Accu-Mold is a plastic engineering and tooling company located in Portage, Michigan. For nearly 40 years, Accu-Mold has been successfully serving our customer’s tooling and molded part needs. Their staff has decades of part design, mold design, mold building and mold processing experience.