Alpine & Nordic Binding Mounting Drill Bits

Durable and long lasting, conventional and long shank, Shop quality 5/16" stepped alpine ski drills are available in the following sizes. All fit 5/16" Binding Mounting Jigs, Jigarex Binding Mounting Jigs and Big Gator drill guides.

• By CE regulation, all current skis have the recommended drill size printed on the ski, either in the mounting area, on the adjacent sidewall or on the tail with the ski dimensions. If there are no drill sizes provided on the ski (ie, custom skis), contacting the manufacturer for their recommendations is your best course of action. If unsure, drill with 3.5mm diameter tip. If metal is present, then use a 4.1mm bit.
• The general rule on alpine ski drill bit sizes is 3.5mm for non-metal skis and 4.1 for metal. There are exceptions, such as a metal binding plate in a non-metal ski, carbon fiber top sheets, etc
• The outside diameter of an alpine screw thread is just over 5mm. The inside diameter of the screw thread (shank) is just over 4mm which matches the tip of a 4.1 diameter bit. Softer materials such as wood or plastic will compress when driving a screw into a 3.5mm hole. Non-compressible materials like metal and carbon should be drilled with the larger diameter, 4.1mm hole so the shank does not compress and damage the material while being driven into the ski.
• Binding Freedom & Quiver Killer stainless steel inserts & heli-coils require a 1/4" tipped bit.
• The minimum depth for a screw for a binding mount is 6mm/1/4". Measure the screw less the binding thickness will provide you minimum drill tip length.
• It is better to err towards a longer tip than one shorter than the embedded screw section length so the bindings can lay tight to the ski.
• The 0.5mm difference between a 7mm vs 7.5mm or 9mm vs 9.5mm is negligible and the bits are interchangeable. (0.5mm is about the thickness of 5 sheets of paper.)
• Make sure this will not exceed the thickness of the ski or snow board.
• The excess depth of a hole deeper than the length of screw will be filled with the glue.
• Tapping skis with metal and carbon top sheets using a 12AB tap is recommended. Tapping all holes regardless of topsheet type or drill tip diameter is recommended. The same tap works for 3.5mm & 4.1mm diameter holes.
• Long shank alpine drill bits are 1 3/4" (4.5cm) longer than standard bits for use mounting jigs and drill guides
• Armada skis require a Double Step bit from 4.1 to 3.5mm.

• NOTE! A double step bit might be the only drill bit you need. Not only is the 4.1mm tip needed for metal and carbon top sheets, the extra diameter might reduce 'volcanoing' on plastic and other top sheet materials.
  

  Available to back order if not in stock.