manufacturer and supplier of lead screws, ball screws, acme screws, bearings, motors Screwtech offers precision thread grinding, on a variety of materials, such as carbon steel, stainless steel, alloy etc. Most forms, tapers, angles and diameter can be accommodated. The threads can be both internal and external. Our internal thread grinding capability is up to 500mm in diameter and 200mm deep. Our external thread grinding capability is up to 320mm in diameter and 800mm long.