Drill Doctor drill bit sharpeners are manufactured by Darex, the same company that makes machines for the professional sharpening industry. Each unit features a high quality motor, a precision chuck for consistent results and a quick-change diamond-grinding wheel. All models will give you excellent results on twist type bits including HSS, masonry, carbide, cobalt and TiN-coated. Drill Doctor machines will not sharpen brad point bits, auger bits, forstner bits, paddle bits or spoon bits.
The DD350X is designed for the home workshop. It sharpens twist bits from 3/32" to 1/2". Comes with a 3-year warranty from the manufacturer.
350X User's Guide.pdf
Drill Bit Anatomy.pdf
Twist Drill Geometry.pdf