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4mm Diamond Core Drill Bit

$13.00

4mm Diamond Core Drill bits are perfect to drill out a hole in a shell, glass, gems or wood without chipping or cracking.  Because it has a hollow core, it's easy to balance on a solid object and "core" it out.   Please use these in water, to preserve the diamond bits and to keep the dust from being inhaled while drilling.

We have 4 sizes: 1.5mm, 2mm, 3mm and 4mm

  • 1.5mm is Michelle’s fave, and fits a 18 gauge jump ring.  Great for delicate shells, and sunrise shells.
  • 2mm sells well, and is Jamie’s fave, cause it fits a 16 gauge jump ring quite nicely and I love chunky jewelry.
  • 3mm is Jason’s fave cause the shank and the drill bit are the same diameter – so it’s easy to drill with!  Perfect for large gauge bangles that need big hole pearls!
  • 4mm is great for cutting through thick beach glass and ceramics.  Handy to have and may last you a while cause it’s super coated and big!   We carry this at the request of our ceramicist friend, Erin!
  • 1 pc.
  • 3mm or 1/8" stainless steel shank with diamond particles electroplated on it
  • Fits the motorized bead reamer AND the flex shaft