So we re not too concerned about long, stringy chips, unless they are irregular and rough. Roughness indicates inadequate lubricity in the cutting fluid, and any binding requires adjusting the cutting parameters or trying a different drill with a more positive geometry or with parabolic flutes. Choosing the right drill, running it at the correct speeds and feeds, and supporting it correctly with fluids, solid workholding and a good machine will produce optimum chips an excellent sign that the operation is giving the best finish possible. Back to the Metrology page Return to Quality Magazine's home page. Make It Straight.
Advanced drills can replace the reamer, as well as the conventional center or starting drill.
Tool wear can affect surface finish. Discoloration of the chips, hole and tool can help pinpoint the cause of poor surface finish. Cutting fluid is important for good finishes.