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Allan Harrington

Tuning Machine Roller Hole Step Drill

HHSS with closeup of brad point and long spurs.

High speed steel step drill for Schallers™, Gotohs™ or any machine with a 10mm (3/8") barrel. For quick and correct fitting of classical guitar tuning machines, the holes that accept the string rollers should be slightly relieved where the roller passes through the outside rib of the guitar head. These custom-made step drills drill relieved holes in one operation, increase accuracy of hole placement, and clear chips quickly.

  • Short length, high speed steel
  • Brad-point style with long spurs
    (Very sharp, protected with hot dip plastic)
  • Black oxide finish
  • Outside diameter = shank size 
  • 27/64" OD, .402" D x 15/16" L step. 1/2" overall length.
  • For all Schaller™ classical machines or
    any roller of approximately .393" (10mm) diameter.

NOTE: This special step drill is intended for drill press use only. It is not intended for use with either the Classical Tuner Drill Jig (SPDJ), or the Headstock Slotting and Drilling Jig (SPHSSJ) – It will damage these jigs. Use only the HSSJ/HSSJ10 Twist Drills with these jigs.

SKU Product Name In Stock Each  
HHSS Roller hole step drill Yes $27.85