Part I of this series here.
Part II of this series here.
For more photos of this process, visit our flickr photostream!
Quick review- here’s what we started with:
And here’s what we’re going for:
How we get from point A to point B has been detailed for you in these last couple of posts. Today we are going to see the raw casting transform into a finished piece of custom jewelry, under the skilled hands of Emily and Jason, my sister and brother-in-law. First, a little snippet of history: This ring was originally designed and made by me for Ben M., a dear friend of my husband Michael. Somehow the ring was lost. There’s always been a suspicion that my youngest child had something to do with it… but without evidence she has full habeas corpus.
(Possibly the culprit behind the first missing ring, but she is now three and knows not to touch Mommy’s creations anymore.)
Ben missed his ring for quite some time, and this year his girlfriend Amanda, who came into the picture after the ring and had not yet seen it, commissioned us to re-create it, as close to memory as possible, for his birthday. We did fall short of the actual day (sorry, Ben!) but he has it now, and is enjoying it once again. Lucky for him, we had exactly one more center stone that matched his old one!
Back to the work at hand:
Here is Jason with the (somewhat) cooled flask, ready to chip out investment. It’s still the approximate temperature of a warm oven, so he protects his hands. Note the trusty screwdriver at the ready.
The sharp screwdriver plunges into the investment, Jason uses leverage to cut and crumble chunks out, careful not to hit the metal inside.
The investment comes out quickly, and once the edges are cleared, Jason can tap on the button to loosen the rest.
Is that shape beginning to look familiar? It is to me!
The metal is still hot to the touch, but the air is cooling it rapidly. In the past 15 minutes the metal has gone from beads of alloy and pure silver (called ‘shot’) to a completely molten stage at over 1200˚F, then hardened into a completely new and different shape! Soon it will leave its warm cocoon of silica plaster and face more heat- this time from friction.
Jason taps a bit more investment off, and the shapes are even more visible. Remember when this was multi-colored wax hanging tenuously to a black rubber mold base?
Standing at the bathroom sink, Jason scrubs the casting off under running water, using an old toothbrush. We make sure to mark the investment toothbrushes so no one eats silica!
Here it is in all its glory:
The powdery investment gives the metal a silky look. I have always loved this look and kind of wish we could leave it intact. Sandblasting gives a nice even matte, but never the exact same fineness of texture as this…
Yes, there is a sapphire in there already… smaller pieces of corundum handle the heat of casting.
Next step:
A good ultrasonic soaking will get off any more investment residue. This is something of a ‘starter’ ultrasonic for the industry, but it worked for the picture.
Doesn’t that blue look appealing? It’s just a cleaner, sorry.
The ring is cut from the sprue, and Jason proceeds to grind the bottom nub off where the sprue fed into the piece.
This is our jeweler’s lathe. We use it for multiple stages of grinding and polishing. The wheel that is on right now is an aluminum oxide composite made by 3M. The wheel rotates at 3,475 RPMs, so friction is considerable. 3M designed the wheel to be porous, which absorbs some of the heat. Jewelry still gets very hot, however, especially a natural conductor like silver!
If Jason would happen to slip and hit his fingernail on that wheel, it would cut through to the quick in about 3 seconds.
A trained hand can roll the ring, cutting the proper contours into the metal as the wheel spins.
Now Jason applies a file to all of the topmost surfaces of the ring. Often a cast will come out with little chunks missing out of the design, sometimes there is a small amount of flashing that needs to be scraped or ground off. Jason is prepping this one for his wife (my sister) to set stones.
The ring is now 80% done. Note the ingenious pink ‘shim’ on Emily’s bench pin. We’re all about technology here!
The next day:
Emily announces her presence by threatening the camera with a Foredom handpiece:
With the handpiece whirring at about 12,000 RPMs, Emily begins to notch the prongs.
Here she trims the height of the smaller side prongs.
After notching the center prongs, Emily checks the fit by slipping the stone into its seat. This particular stone is a checkerboard cut topaz.
It fits! Now to level off the prongs:
I build the prongs a little longer than needed in the wax, in case of a tighter fit. Emily always cuts them back in the metal for a perfect fit.
Okay! It’s in, and the prongs are now set to be bent over the top of the stone:
It may look like she’s just crunching down on that stone with pliers…
… she is, just very, very carefully. It took her years to learn how to wrangle those pliers just right!
Setting the sidestone, an aquamarine:
Checking the settings for wiggle:
It might look like Emily is dragging that file right across the top of the stone, but she’s actually working on the silver immediately on top of the topaz. Once the prongs are notched and bent, there are always rough spots to be smoothed down.
Now Emily takes a medium-grit silicon dioxide wheel to the prongs:
The silver needs to be ground gently, almost massaged into the shape we want it to be. One false slip of that wheel, however, and there will be a nice scuff mark halfway across the top of the stone. Stone setting requires an incredible mixture of strength and grace…
Now it’s off to the lathe again, this time with a compact muslin wheel embedded with polish rouge:
One more dip in the cleaner, some polishing on a finishing wheel, and Ben’s ring is complete!
Happy birthday, Ben! Don’t lose it this time. Amanda: thanks! :)
Part I of this series here.
Part II of this series here.
For more photos of this process, visit our flickr photostream.
For your own custom experience, email us.
