Alpha Gold Series 5/16 inch Jobber Drill Bit When you go to buy a drill bit, what are you needing ? Just a drill ? or do you actually want HOLES ? Rigorous independent testing has proven that the Gold Series Drills outperform other Australian drills on the market by more than 30% - giving you more holes for your dollar in every single drill bit ! DRILL FEATURES M2 HSS Fully ground M2 HSS material increases drill life Titanium Nitride coating reduces heat and increases lubricity for extended life 135 Degree Split Point cuts faster and reduces wandering Alpha Gold Series Drills are packaged in a reusable plastic hang pack, keeping your drills safe, clean and dry. All Gold Series Drills are also available as a single piece in our carded range. Click here to view the carded version of the 5/16 inch Gold Series Jobber Drill. Click here to watch a video on the Alpha Gold Series Jobber Drills. Click here to find your closest Alpha Distributor. TECHNICAL DATA Overall Length 98mm Flute Length 66mm Stainless Steel RPM 484 Tool Steel RPM 726 Cast Iron RPM 968 Malleable Iron RPM 1089 Medium Carbon Steel RPM 1210 Free Cutting Steel RPM 1734 Alum, Brass, Plastic RPM 2460 Wood RPM 3669 Feed per RPM (mm / rev) .15-.25 Standard pack Qty 10 DRILLING PRACTICE The flute form, web thickness and split point of the standard Alpha drills are suitable for most materials forming fine chips. For effective drilling, the rigidity of the drilland work piece are most important. The shorter the flute length the more rigid the drill. Long drills must be adequately supported to reduce vibration. The following are important in drill use : Clamp the work piece securely Select the correct speed and feed Use an appropriate coolant or lubricant Ensure the shank is securely held. Avoid using worn drill chucks as the drill may slip during use. Regrind the point or replace the drill before it dulls, do not force a worn drill. When deep hole drilling, withdraw frequently to clear the chips ( deep holes start at 4X the diameter) For stainless steel, manganese and high tensile steels, do not allow the drill to swell as it will cause work-hardening. Use a slower speed and heavier feed for these materials.