For those of you who are interested in our handcrafting process and attention to details, here is a description of all the steps that compose the craftsmanship journey of our cufflinks.
Every new design starts with various sketches and iterations. Nicolas, the founder and President of Fils Unique, designs each of them.
2. CAD 3D Design
The designs are reproduced in 3D using a CAD software. It is the 3D prototype.
3. Model Making - 3D prototype
We 3D print the 3D prototype in wax with a cutting edge technology 3D printer. The wax design that comes out of the printer is the master wax model. It is then reviewed, inspected, scrutinized, examined, analyzed, evaluated (there are other synonyms but you get it).
4. Hand finishing and detailing
3D technology provides a lot of possibility but doesn‘t replace the eye for details. We progressively fine-tune the master wax model by hand-filing its surface, carving and engraving additional tiny details, embossing and shaping it until it reaches the perfect level of details, curves or lines and proportions.
5. Silicon Mold Making
A silicon mold is made of the original wax master model. Liquid silicon is poured into a frame containing the master wax model to form, when cured, a silicon mold encapsulating the master wax model.
Silicon molds are quite expensive to make but they are the best possible molds because they allow less than 1% shrinkage. No other material reaches that result. Again, Quality first.
6. Silicon Mold Cutting
When the silicon mold has cured overnight, the silicon mold is cut in a way that provides the best angles and lines. The master wax model (remember step 3 above?) is removed and leaves an empty space that has the shape of the master wax model.
7. Wax Reproductions and Quality Check
The hollow silicon mold can then be used to re-inject hot wax and reproduce the master model afterwards. Each wax reproduction is cleaned by hand and the parting line appearing where the two parts of the mold came together is removed. Each wax reproduction is inspected individually. The quality of the reproduction wax is generally the most underrated part of the casting process. Any defects in the wax reproduction, like distortion or internal air bubbles, will dramatically affect the end results of the casting.
8. Building a Tree
The wax copy is sprued with a treelike structure of wax. A “sprue” is the passage through which liquid metal is introduced into a mold. It controls the flow of molten metal into the casting mold and it is thus a very important part of the casting process. If the sprue is not large enough, the molten metal will not flow smoothly into the casting mold and the final model will have defects and irregularities. Our artisans ensure that each wax is attached with the perfect sprue position (angle, size, thickness).
The treelike structure of wax, with all wax reproduction models attached thereto, is put in place vertically in a steel container (the “flask”).
The flask is thereafter filled (“invested”) with investment powder and water that will solidify when heated.
10. Vacuuming the Investment
An air-vacuum process is used to remove all bubbles present in the investment liquid to make sure that there is no hollow space in the investment.
11. Burnout of the Invested Flask
Once our trees are invested and properly air- vacuumed, they are ready to go into our burnout ovens. The invested flask is heated to 1350 F°. The wax present in the investment burns and evaporates during that process leaving a hollow space in the hardened investment.
12. Cooling of the Flask
The flask is then removed from the oven and left aside to cool down.
13. Metal Casting
The cold flask is put into a centrifugal casting machine that uses the weight of the metal and centrifugal force to fill the invested flask. As our models are very detailed and delicate, more force is needed to push the molten metal into the tiny areas of the invested flask.
Too little force and the invested flask doesn’t fill properly. Too much force and you run the risk of blowing the flask.
The idea is to have a steady, constant pressure pushing or pulling the molten metal into the invested flask. Only experienced craftsmen can achieve the perfect balance to cast silver (and other metals) perfectly.
14. Removal of Investment
When the molten metal has solidified and cooled down in the investment, the invested flask is immersed in water. That process entirely removes the investment and leaves only a metal tree (silver, gold, etc.) in the flask.
15. Removal of Casted Pieces from the Metal Tree
We are finally near the end of the process. It is time to carefully remove the castings from the tree. We delicately saw each piece off the tree and file them to smoothen the surface where the sprues were placed.
16. Quality control
A first quality control is made at this point to ensure that the casting doesn’t show irregularities or defects and complies with our exacting standards.
Our jewelers assemble the cufflink with their back. It requires the insertion of a steel spring in-between the cufflink closure back and the cufflink bridge. The steel spring maintains a pressure and a tension so that the closure back stays perfectly in open or close position.
Our master polisher starts the finishing process and polishes each piece by hand using different steps:
The casted cufflinks are put in small batches in a superfine tumbler. Metal tumbling is used to burnish, clean, lightly polish, prepare parts for further finishing, and break off die cast runners. A barrel is filled with mater, lubricants and a medium (small steel pins or silicon pins). The models are placed in the tumbler and then rotated for several hours, very gently, to keep a beautiful finish. The friction with the pins gently removes the outer layer of the casted metal and revels a first shine of the piece.
Designs with sharp edges require an additional lapping process to remove microscopic scratches on flat surfaces.
All traces of filing or sanding marks removed, leaves a “dullish” finish. The surface needs to be refined.
Metal is brought to a high final shine with the use of the polishing wheel in conjunction with compounds. We then clean the cufflinks and use a chamois for the soft, finishing touch.
Our master enamellers receive the final piece to meticulously apply the various colors onto the design. Our enamellers have decades of experience in the jewelry industry and, more specifically, in the restoration of Fabergé eggs and the hand painting of luxury watches dials. Each design is painted by hand, individually.
Our enamellers use magnifying glasses to pain the tiny details onto each design. A mistake and one has to remove the applied (and cured enamel) and restart from scratch.
Some designs require up to 4 hours of painting on each pair. Again, good things take time to make.
20. Final inspection
Each pair of cufflinks is inspected individually and receives its warranty card only if our standards are met.
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