Neat looking shells!
The first dots that I ever made, I rounded with a file...that was a pain. I soon switched to diamonds and snowflakes...a lot easier to make!
You COULD swipe a trick from telescope makers that have to drill holes in the primaries of Cassegrainian telescopes.
You find a piece of copper tubing the diameter of the hole you need to make...in your case you would be looking for the INSIDE diameter...
Cut three, four, five or so notches in the end of the tubing.
Clamp your piece of glass (or your shell) in place...chuck up the piece of tubing.
You also need some sort of mild abrasive. Telescope makers have is laying around. I would think that polishing rouge would work. Make a slurry of rouge and water. Put it on your piece of shell.
Still with me?
You also (the list of "alsos" is over now) need a weight that you can attach to one of the handles on the drill press on some sort of string. Not a heavy weight, just something that will keep a continuous, light pressue on the working end of the tubing.
Put the grinding slurry on your shell. Power up the drill press at low speed. Lower it into the slurry/shell...and the weight on the handle of the drill press will keep it in contact with the shell...
Sit back and drink a cup of coffee, read a book, or practice the guitar, while the tubing grinds its way through.
Make sure the slurry is always surrounding the cutter/tubing.
After it cuts through...push it out of the tubing...and you should have a shell dot.
Of course I have never tried that with shell, but I have drilled through telescope mirrors and beer bottles that way.
Wouldn't you know it! There is a
YouTube video of a telescope mirror being drilled!
