SteveB wrote:
I'm helping a partially blind friend. He has some small pieces of polished
Brazilian quartz he wants to drill a hole into. I have found several
suppliers on line that will sell 1/16" and 1/8" diamond bits for reasonable
prices, around $15 per. Slightly less when bought in threes.

Is this what he needs to drill these holes? I know he needs to use coolant,
and set it up in a drill press. Info on what would be the best way to do
this appreciated.

Steve



Now you have mentioned what the holes are for, ie hanging up the agate
to make wind chimes,
Have you considered any other way of hanging said agate?
There are many other solutions to this question,
I list a few that come to mind
1. use some wire to make a "U" shaped loop with the wire ends bent back
on themselves to increase the contact area on the agate sides.
Then 2 part epoxy to the agate.
2. a similar idea but using some thin strip some 1/8 in wide by say 1/32
thick. Epoxy in place as in 1.
3. if the agate is say 1/2in wide by 1/8in thick, cut a groove each side
into the 1/8in edge. String up using the grooves to hold the agate.
Use the stone slitting saw to do this.
4. If you can do 3. above extend this idea to make a clip with rt/angle
ends indexing in the slots. epoxy in place.

My local glass works use arrow end tungsten carbide to drill holes.
Ive a set of diamond core drills the smallest is 1/6in od. Water is
pumped down the core via a oring sealed head. Otherwise it goes into an
ordinary drill press.

hope this helps.
Ted
Dorset
UK.