Tube settings woes

Hi all,

I am wondering if anyone has advice for me on setting faceted stones
into tube settings.

When I finish drilling out the seat and set the stone into it, it is
perfectly straight - I check this with my loupe. But when I start to
push the bezel over the edges the stone slides slightly, and it ends
up oh so slightly crooked. Which is really frustrating.

I drill the tubing til the stone sits with its girdle just below the
bezel edge… is that not deep enough?

For a 3 mm stone I am using a 3 mm bur - is the stone sliding
because the seat is too big? Sometimes I use a round bur (per Mr
Cogswell’s book) and then finish with a setting bur. Should I use a
smaller bur than the stone, ie 2.9 mm for a 3 mm stone?

Once the stone is in there and looks straight, I use a bezel pusher
to push down the 4 corners, then switch to my hammer handpiece to
finish the bezel. Sometimes, because of where the setting is and
lack of clearance, etc, I have to use the hammer handpiece to do the
4 corners too. I am trying to hold the handpiece (or pusher) against
the bezel and roll it upwards over the stone without pushing it too
hard- ie let the tool do the work. I have my finger pressed over the
stone while doing the 4 corners to keep it flat. Obviously not
working all that well.

Any advice is sincerely appreciated!

Thanks so much!
Mary Barker

Hi Mary,

If you have a lot to do, have you tried a setting punch (name?)?
This is a punch with a conical hole that just fits over the bezel - a
few taps and the bezel holds the stone nicely.

Because setting punches cover a very limited size of setting, they
might be uneconomical for just a few settings. Unless, of course, you
have access to a lathe on which you could make one in about 5
minutes.

Regards, Gary Wooding

For a 3 mm stone I am using a 3 mm bur - is the stone sliding
because the seat is too big? 

You got it! Use 2.9mm and finish with 3 mm held in pinvise using
hands only. No machine!

Leonid Surpin

When I finish drilling out the seat and set the stone into it, it
is perfectly straight - I check this with my loupe. But when I
start to push the bezel over the edges the stone slides slightly,
and it ends up oh so slightly crooked. 

If everything is just the right size and you have cut a good seat,
this should not happen. However, that isn’t always the way it turns
out, plus some stones are cut with a rounded belly that makes it very
hard to keep them from slipping around.

My solution to this is to begin the burnishing process with a setting
punch. I mean the kind that comes in a set with one handle-- the
punches are various-sized cylinders with a conical concave opening in
the bottom. Choose one that is about twice the width of the tube
setting, press it down over the setting very hard and rotate the
handle in very small circles. This gets the edges of the setting all
moving in at the same time, capturing the stone. When you loupe it,
you should see an angle of about 45 degrees at the top. Then I use a
curved steel burnisher to finish laying the setting down onto the
surface of the stone and give it a beautiful shiny surface.

Noel