9OPERATION Screwdriving operationPlace the point of the driver bit in the screw head and applypressure to the tool. Start the tool slowly and then increasethe speed gradually. Release the trigger just as the screwbottoms out. If the trigger is not released, the screw may stripout the hole or the screw and/or bit may be damaged.NOTE:• Make sure that the driver bit is inserted straight in thescrew head, or the screw and/or bit may be damaged.• When driving wood screws, predrill pilot holes to makedriving easier and to prevent splitting of the workpiece.See the chart.Drilling operationDrilling in woodWhen drilling in wood, the best results are obtained withwood drills equipped with a guide screw. The guide screwmakes drilling easier by pulling the bit into the workpiece.Drilling in metalTo prevent the bit from slipping when starting a hole, makean indentation with a center-punch and hammer at the pointto be drilled. Place the point of the bit in the indentation andstart drilling.Use a cutting lubricant when drilling metals. The exceptionsare iron and brass which should be drilled dry.CAUTION:• Pressing excessively on the tool will not speed up thedrilling. In fact, this excessive pressure will only serve todamage the tip of your bit, decrease the toolperformance and shorten the service life of the tool.• There is a tremendous force exerted on the tool/bit at thetime of hole break through. Hold the tool firmly and exertcare when the bit begins to break through the workpiece.Nominal diameter ofwood screw (mm)3.1 (1/8”)3.5 (9/64”)3.8 (5/32”)4.5 (11/64”)Recommended sizeof pilot hole (mm)2.0 - 2.2 (5/64” - 3/32”)2.2 - 2.5 (3/32” - 3/32”)2.5 - 2.8 (3/32” - 7/64”)2.9 - 3.2 (7/64” - 1/8”)002138