Padding

• Place the shell on a soft surface--such as leather, closed cell foam or soft wood--before drilling. This prevents excessive pressure that can cause the shell to shatter and keeps the shell from moving during drilling. J. Abruscato, author of "Whizbangers and Wonderments: Science Activities for Children," recommends taping each shell in place on the pad. This keeps both hands free to operate the drill or rotary tool and prevents possible injury.
  
  

Wetting

• Drip water on the area of the shell that needs to be drilled. This allows the drill bit to pass through the shell with less resistance. According to Dremel, a high-speed, hand-held rotary tool maker, dry shells take longer to drill.
  
  

Tools and Technique

• Attach a cone-point diamond burring bit to a hand-held, high-speed rotary tool. Use gentle, even pressure to bore a hole through the shell. Turn the shell over and deburr the hole using the same bit from the opposite side. This results in a smooth hole with less chance of chipping. Shells edges can cut just like broken glass.
  
  

Safety Tips

• Sculptor Eva Jung advises that long hair be worn in a bun, not just in a pony tail, when using a hand-held high-speed rotary tool or other spinning power tool. "...I was working on a chess piece when the bit itself snagged in my own long hair...in a ponytail...and wound itself all the way up to my scalp. I now had the flexshaft dangling from my head as I fumbled to turn the...thing off. It was biting in to my head, but luckily I had a grinder on it instead of a cutter. I'm sure a cutting bit would have been MUCH worse."