Using seat check or green disclosure powder


I’m flush mounting fancy stone shapes using Blaine Lewis’s method
according to his video. I’m working on this one particular trillion
stone. I’ve got the bearing cut however the stone rocks or pivots and
doesn’t sit flat in the bearing/seat.

Using the Seat Check (green disclosure powder I purchased from Rio),
I’m assuming any green seat check that was removed by the pivoting
stone rubbing against the metal is an area that needs some metal

You spray the seat check on the seat, pop in the stone, let it pivot
around in the seat using your fingernail, and any exposed metal is
where I would need to remove some metal?

I’m asking in hopes that there is someone who has experience using
Seat Check. I don’t want to keep removing metal and find that I’ve
removed too much.


I use a similar method to check seating, although I use a black felt

A technique similar to what Mr Lewis describes in his flush setting
video. Also Kate Wolf teaches a similar technique to get seats
correct in wax.

Once you have the seat roughed in, use the reveal to spot the
contact points. Where stone meets seat the rocking will have removed
the reveal. Remove JUST A LITTLE of the seat at those points, and
try stone in the seat again.

A very very little bit of metal in contact can be causing the
"rocking". The old saying “cut a little, look a lot” applies here.
Go slow, using you reveal powder as often as needed so you know
exactly what metal to remove.

That is exactly the way it is used. In my opinion it is a must for
setting fancy cut stones, especially in a flush setting situation.

My understanding is that there is a little piece of metal where the
pavilion should be ‘resting’.

Examine with a 10x loupe for any amount of metal, the stone is
rocking on this piece of metal. Why buy some extra powder? Just use
your loupe & realize these things do happen. I’d use a fine pointed
#007-bud bur & lightly file away the metal,…just a small amount
will make any stone rock! Hold the bur in a vertical position, this
procedure will grind anything away.

Think of another easier method; if the stone is rocking at the
12:00-6:00 position. The offending problems are at the 3:00-9:00
position on the setting. try this, I use this process all the time.

Try not to use a round bur. why? it has a limited ‘contact spot’.

Also re-examine the ‘bearing-cuts’ you made for the girdle. any thin
slice of metal will be an annoying factor in Gypsy/Flush
settings!..“Trillions are great, but they mustn’t rock!”…:>)

Gerry Lewy

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I’ve used Seat Check, especially when I am very close to perfect
fitting. Scary expensive colored stones demand very careful
handling. When I really want to know(see) what’s going on underneath
the stone, I spray the green powder on the seat, carefully place the
stone in, and apply mild top down pressure with a ghost of a rocking
intent on the stone. Carefully lift the stone out, and one will find
marked impressions where contact is made. Remove the material where
those marks are. Repeat process as needed to achieve a more flush

This is what the Dentist does when he/she wants to see how your
teeth contact each other to achieve a more proper fit on your bite.

Mark L.

Using the Seat Check (green disclosure powder I purchased from
Rio), I'm assuming any green seat check that was removed by the
pivoting stone rubbing against the metal is an area that needs some
metal removed? 

That sounds right.

I use Articulating film that I buy from a dental supply house (the
same place I get my mounted bristle brushes, pink rubber wheels,
etc.) With it, I grind off wherever there are marks left by the film.

Here’s a company that gives out free samples:

Paf Dvorak

You spray the seat check on the seat, pop in the stone, let it
pivot around in the seat using your fingernail, and any exposed
metal is where I would need to remove some metal? 

The exposed metal is where the stone was able to contact, rubbing off
the disclosure powder (or whatever you use. Magic marker, machinists
layout dye, something else…) However, this does not mean every
exposed spot needs metal removed. Think in terms of a teeter-totter
on the playground. The bar swings up and down over a center pivot
point, and at each swing, contacts the ground at one end or the
other. Your stone is doing the same. You don’t want to be removing
the metal at the ends of the swing, as those are low points the stone
can touch.

What you want to find are the high points on which its pivoting.
Removing a tad of metal there will drop the stone down slightly,
lessening the amount by which it can shift. Keep working that until
it’s steady and level. Note that you won’t ever (well, never say
“never”…) get it to contact all the way around.

often, what you’ll get is decent contact at three points spread
around the stone.

On trillions you’ll usually want this good contact to be supporting
the points of the stone, since if you support at the long sides,
leaving the points unsupported, then tightening the stone can result
in what amounts to a nut cracker geometry, causing you to break off
the tips. The closer you can get to even support at more than the
minimum of three spots, the better and safer, but just keep in mind
that without some sort of cutter that actually cuts a match to the
stone shape (like a round burr can do with a round stone), it’s hard
to get full contact all the way around. Not impossible, but hard,
especially with softer stones. One hint, you may find, for some
situations, that using a manual graver to shave thin amounts of
metal off the high spots, gives you better control over tiny
adjustments than using a bur in a power tool. Takes a bit of
practice, but it’s one of those cases where sometimes the old time
honored tools are capable of better results, even if sometimes slower
(or maybe because they’re slower…)

Hope that helps
Peter Rowe

1 Like

If you have used the powder and marked the stone so you know which
side of the triangle you have placed where in the setting and have
removed metal ( or better yet used a Foredom All- Set system!)t’s
probably the stone that is cut irregularly: particularly on
inexpensive trillions you will find the depth differs from girdle to
culet on all sides. Pick a center line through the stone and divide
it using a grease pencil or painters tape into 3rd’s- that will make
it easier to get all the dimensions you need to apply to the
setting’s corresponding steps. The distance and depth of the girdle
on the 3 sides is what will matter to you if flush setting it. Once
you have gotten the true measurement of the stone and checked what
you have already done to the setting you are removing metal from,
turn the stone until it either corresponds to work already done or
take more off of the thinnest side to make it sit flat. If you keep
taking metal from the deepest side/angle you will never get it flat
on top as it will always tilt to that side.

Marking it off with a scribe use a hart bur or whatever you like as
a setting bur to remove the smallest amount of metal at a time, then
recheck the stone by trying in the setting. One trick is to take a
hart bur a few points smaller than the stone and grind off the peak
so you have a flat cutting disk. This way you get a relatively flat
seat if doing it by hand without gravers and without any question of
gouging into the side to start metal removal. Otherwise sharpen an
onglette or round graver and using magnification cut around the side
necessary to make it sit flat and clean up any burrs or peaks that
may have been left behind in previous operations in cutting the
setting. If there is too much difference between the amount you need
to remove and what is left to cut while maintaining the design, you
may be able to take the top down with a diamond sleeve placed onto a
rubber sanding drum bit or grinder and basically re-do the setting.
If not scrap it and start over! There comes a point in a gypsy setting
when too much metal is removed and the stone sits far below the point
where the stone is just below the metal to protect it and it looks
silly!Alternatively if you know the stone is off/cut poorly but still
want to use it, come from underneath the setting and remove what is
necessary to insure the stone isn’t going to get chipped in daily use
and either add some tabs or cut some beads to hold it in place or
measuring carefully make a tight fitting bearing wire so the stone
snaps into place when inserted into /securely inside the setting. you
may need to cut a few beads to hold it all in place from the
underside if it isn’t perfectly flat from any angle you try. Just
remember to use something to mark side a, b,and c so you are trying
it in the same place each time… rer


Just wanted to say thanks for all the input! Some really good tips

Much appreciated!

Hi Chris,

I’m a student of Blaine’s and you’ve got it right. You can use a
graver or a bur to remove metal that is exposed. I like using a
graver for those last fine adjustments. Good luck!

Donna W
Huntsville, AL