The machine reamers with straight shank, DIN 212 / UNI 6853, made of HSSE steel with straight flutes form A-C, are cutting tools designed for finishing, sizing and dimensional correction of existing holes on conventional and CNC machine tools. They are used when a hole previously produced by drilling, boring or rough machining must be brought to its final size with accuracy, good roundness, controlled surface finish and dimensional repeatability.

A reamer is not designed to create the hole, but to finish it by removing a small and controlled amount of material from the internal diameter. This operation improves the geometry of the seat, corrects minor irregularities left by the previous tool and produces a hole suitable for precise mechanical fits with dowel pins, pins, bushes, small shafts, guides, centering components and technical assembly parts.

The HSSE steel construction provides higher wear resistance than standard HSS and ensures good cutting edge stability in professional machining operations. It is suitable for steels, alloys, cast irons, ferrous and non-ferrous materials, depending on the machine, coolant, stock allowance and cutting parameters used.

The straight shank allows mounting in drill chucks, collet holders, clamping sleeves and suitable toolholding systems. To obtain an accurate hole, clamping must be rigid, coaxial and low-runout. Final hole quality depends not only on the reamer, but also on toolholder concentricity, machine rigidity, correct alignment between tool and hole and stable workpiece clamping.

The straight flutes form A-C are suitable for reaming operations requiring simple, stable and controlled cutting behavior. This geometry is used for general reaming applications in through holes or blind holes, depending on chip evacuation and working conditions. Straight flutes provide a regular finish when the hole has been correctly prepared and the machine ensures constant feed and good rigidity.

For best results, the hole must be prepared with a suitable stock allowance. If the pre-hole is too small, the reamer must remove too much material, increasing cutting force, heat, wear and risk of sticking. If the pre-hole is too close to the final size, the tool may not cut uniformly over the full surface, leaving geometric errors, scoring or uneven finish.

During use, constant feed, suitable lubrication and accurate alignment between tool and hole are recommended. Vibration, misalignment, unstable clamping and reverse rotation while the reamer is inside the hole should be avoided. Proper lubrication reduces friction and heat, improves surface finish, supports chip control and helps increase tool life.

These reamers are suitable for precision machine shops, CNC departments, machine building, automotive, toolrooms, industrial maintenance, mechanical production and subcontract machining. They are particularly useful for producing calibrated holes, cylindrical seats, holes for dowel pins, pins, bushes and components where hole accuracy directly affects assembly and function.

The HSSE machine reamers with straight shank and straight flutes form A-C are a professional solution for finishing accurate and repeatable holes on conventional and CNC machine tools. The combination of DIN 212 / UNI 6853 standard, HSSE steel, straight shank and straight flute geometry enables reliable machining, dimensional control and good hole quality.