ITEM NAME:8pcs HSS Countersink Tap Drill Bit Set, Combination Hex Shank Titanium Scre A1G1 8pcs HSS Countersink Tap Drill Bit Set, Combination Hex Shank Titanium Scre A1G1 suitable for drilling wood, plastic, fine copper, aluminum and other soft metals (5-6 mm), not for hard materials (eg steel sheet) . Practical fittings, 1/4 inch hex shank, quick and easy to change. Self-centering point, no need assistance in center drilling or center punching.Drilling and tapping at the same time, one-step processing. Greatly decrease processing steps, save time and improve working efficiency. When drilling a hole, you should inject water at the same time to cool down the drill bit. This will help you to increase the value of the drills. If you can not cool down the drill bit when drilling holes, the drilling rate should not be too high, and you should not drill holes too frequently. The composite tap is preferably operated on a bench drill or a tapping machine. The thickness of the workpiece is less than 5 mm. When using it, the lubricant is applied to the tap. If the hand drill is used, the thickness needs to be within 2 mm, otherwise the tap is easy to break (because the hand The drill cannot always be operated vertically and at a constant speed). colour:Silver Material:High speed steel size: 1/4inch (6.35mm) hex shank M3, 2*M4, M5,2*M6, M8, M10 Package Contents: 8* Hex Shank Tap Drill Bits
