Steptool Relief Grinding Fixture Manual

Instruction manual for the Harig Steptool Relief Grinding Fixture, a comprehensive workshop reference for precision tool sharpening and grinding. This service manual covers two core sections: Section I provides detailed techniques for grinding and sharpening helix-point twist drills on surface tool and cutter grinders, while Section II addresses relief grinding methods for step drills, taps, countersinks, piloted tools, and other cutting implements. Includes complete nomenclature and identification of all fixture components—timing pin, collar, index hub, adjustable cam, spindle lock, and drill collet—essential for proper setup and operation. Step-by-step grinding procedures guide users through wheel selection, fixture alignment, and tool positioning. Comprehensive diagrams illustrate seven helix-point profiles: general purpose, non-ferrous and plastic point, trepan/spur-point, tough steel or iron point, sheet metal point, and protected corner point configurations. Detailed technical drawings of extreme and moderate helix-point geometries label all critical angles and features—apex angle, lip relief angle, helix angle, margin, heel of land, helicoid area, tip angle, and S-shape apex edge—making this an essential troubleshooting and maintenance resource for toolroom professionals and anyone performing precision drill or cutting-tool restoration.