I enlarge the holes in already-drilled beads & pearls by using my
dremel with varying drill bits. I hold the bead in my left hand
submerged in a bowl of water and then drill it with my right hand. I
do it outside because it can be messy and I wear my visor so I can
see the hole and my respirator so I don’t breathe the dust.
For pearls I use carbide drill bits; for stone beads I used
diamond-coated drill bits. Sometimes I have to make several passes
using different size bits because I don’t like to force it. Also,
pre-position a band-aid on your left middle finger for when you miss
the hole in the bead. Sometimes I also use a pearl vise I got from
Rio several years ago for $80 that will hold the bead for you, but
you can do it without. Drill wet.
Carol