Page 153 - Demo

151GENERAL PURPOSE DRILLINGProblem Cause Solutionhole diameter out of tolerance%u2022 Unsuitable cutting conditions.%u2022 If hole size is too large, increase cutting speed or reduce feed. If hole size is too small, reduce cutting speed or increase feed.%u2022 Poor clamping of the chuck.%u2022 Check the clamping. Use hydraulic clamping chuck, MAXIN power chuck or a shrink system.%u2022 Large runout. %u2022 Make sure that the drill%u2019s runout is within 0.02 mm (radial & axial).%u2022 Worn out center point (chisel).%u2022 Regrind cutting edge or replace the drill.hole not straight %u2022 Insufficient chip evacuation.%u2022 Use pecking cycle.%u2022 Poor clamping of the chuck.%u2022 Check the clamping. Use hydraulic clamping chuck, MAXIN power chuck or a shrink system. %u2022 Workpiece rigidity. %u2022 Increase workpiece chucking force.%u2022 Worn out drill center point (chisel).%u2022 Regrind cutting edge.%u2022 Unsuitable cutting conditions.%u2022 Increase feed. When spot drilling, reduce feed.drill breakage %u2022 Poor clamping of the chuck.%u2022 Check the clamping. Use hydraulic clamping chuck, MAXIN power chuck or a shrink system. %u2022 Workpiece movement. %u2022 Increase workpiece chucking force.%u2022 Wrong drill. %u2022 Check drill type and drilling depth, cooling system and workpiece material.%u2022 Insufficient coolant. %u2022 Check cooling lubricant. Increase coolant pressure. In the case of external coolant supply, improve jet direction and add cooling jets.%u2022 Unsuitable cutting conditions.%u2022 Reduce feed.%u2022 Worn out drill center point (chisel).%u2022 Regrind cutting edge.%u2022 Insufficient chip evacuation.%u2022 Use pecking cycle.