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Solid Carbide Drills Deep-Hole Drills Application Rules 1) Pilot Drill Hole — IMPORTANT! • The point angle of the pilot drill must be greater than one of the following deep-hole drills to protect its cutting corners. • The diameter size of the pilot drill must be greater than one of the deep-hole drills to enable easy fi t and protect margin lands. The required difference in diameter is covered by design with the different position of tolerance. • Drill Ø = nominal Ø up to nominal +0,010mm. • Depth of pilot hole: minimum 2 x D. • Deeper pilot holes are preferable. Recommendations: • Use a conical (TDS*) or split-point drill to pilot (do not use a TDG, VariDrill ™ , or TDS 12 x D or any competitive drill). • Check the pilot drill for wear, which can lead to premature wear on the TDD10* cutting edge and possibly catastrophic failure. • TOP DRILL S ™ for steel or cast iron (TDS4* series) and TOP DRILL S + ™ for multiple applications (TDS501* series 3 x D and TD502* series 5 x D) with a 140° point angle are recommended. • TDS503* series 8 x D and TDS504* series 12 x D is not recommended as the point angle is 132°! 2) Feed TDD10* into Pilot Hole • Max 500 RPM and recommended feed rate; no rapid traverse. • Run anti-clockwise, especially in horizontal applications to protect the cutting edge, when entering the pilot hole. • Depth: 1mm above the bottom of pilot hole. • Feed TDD10* into pilot hole Recommendations: • Reduce cutting speed to minimise imbalances in machine spindle/adaptor! 3) Drill Hole Cutting Parameters: Start recommended speed and feed rate at 1mm from the bottom of the pilot hole, clockwise. Recommendations: • DO NOT PECK OR DWELL up to 30 x D! • With long-chipping steel materials, it may be necessary to increase feed rate by 10–20% to provide optimal chip control. • For long-chipping aluminium materials, it may be necessary to decrease feed rate and increase speed. • Reduce feed rate on angled exits and crossholes by 50–60%. HP feed recommendations are usually higher than with competitive SC drills! 4) Drill Retraction Cutting Parameters: 50–500 RPM and feed rate 2–6 m/min. Recommendations: To achieve the best tool performance, we recommend using the deep-hole drill with a hydraulic chuck. Reduce cutting speed to minimise imbalances in machine spindle/adaptor! • If the pilot holes are close to each other, chips can fall into the neighboring hole. • Do not enter a pilot hole that might contain chips with a deep hole drill to avoid chip jamming, wear, or breakage. • If required holes are close to each other, use smart drilling strategies, make sure the pilot holes are getting properly cleaned, or switch to horizontal drilling. Horizontal drilling process preferred for optimum chip evacuation. T116 widia.com 5) Vertical Applications