I use tumbled stones and slabs, cabochons, beach pebbles, raw crystals, sea glass and pottery shards in my jewelry making. Because I use cold connections to join much of my work, I have to layer different types of materials, so I drill lots of holes in metal and delicate objects like stone or sea glass.
To drill these types of materials you must submerge the hard object to be drilled in water, and very often stones, sea glass and shards are also curved, making it a challenge to drill a straight hole through them without cracking or breakage. This is my favorite method for securing hard materials during underwater drilling to prevent hand fatigue, slipping, cracking the stone or bent and broken diamond drill bits.
What you need
• Shallow Pyrex dish
• Dop wax or beeswax candle
• Very fine diamond drill — 1mm to 1.5mm at the most
• Flex shaft with #30 Hand Piece
• Assorted diamond attachments in a range of diameters and grits
Step 1 In a very dry and clean ceramic or Pyrex glass dish, create a mound of molten to semi-molten wax and form a base for whatever object you intend to drill. I make the wax mound equal to the thickness of the object, erring on the side of more rather than less wax.
Step 2 Once you’ve melted a thick base, melt another top coat of wax and quickly press the object you intend to drill into the still-liquid wax. At this point, you can “push” additional molten wax up and over the edges of the object if it is particularly curvy. Let the wax cool completely.
Step 3 You must drill wet when using diamond burs, because water cools both the object and the hard-working drill bit. Pour water in the dish to slightly cover the surface of the object and put on your goggles.
Step 4 Get comfortable. You will be drilling for quite some time, especially on stones harder than about 6 on the Mohs scale. Using the smallest diamond drill bit, drill a pilot hole all the way through the object. I drill for a few seconds, remove the drill from the hole to clear sludge, and go back to drilling. This initial drilling can take up to 20 minutes for thick quartz, so be patient…
Note: I use a miniscule 1mm drill bit for drilling pilot holes. It is inevitable that the drilled hole will “blow out” on the back, so a small hole can be enlarged and cleaned up later, after using a small diameter starting bit.
Step 5 Once you’ve drilled completely through, pop the stone off the wax. If it sticks, pour out the water, let everything dry, and put the dish in the freezer for a few minutes to chill and harden the dop wax. Most of the time, the cold wax will readily release the stone. Clean off any lingering wax with a cotton swab dipped in Acetone. Step 6 Inspect the hole. If there are no cracks, continue to a larger drill bit and gradually enlarge the opening. I work on the front of the object, then from back to front with the next bit, then front to back with the next, continuing until I have created a hole at the final diameter. At that point, I use a finer grit diamond bur to grind the openings completely smooth. Very often I will finish with a fine-grit ball bur to create a gentle taper at the top and bottom edges of the drilled hole to prevent chipping.