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The Hungry Knife Pendant Process

The Hungry Knife Pendant Process: From Pen To Pendant.
Step 1, Concept
It (almost) always begins with a drawing. Sometimes just a rough thumbnail, but occasionally a full-color rendering. Drawing proves the merit of the idea. It’s a ‘paper test’. The thing I imagine won’t always work on paper. Engineering problems don’t present themselves until I make a drawing, which serves as a working schematic.

Step 2, Computer Graphics
Once satisfied with the concept sketch, the design is recreated using vector graphics software. Vector graphics are a form of computer graphics in which designs are created directly from geometric shapes defined on a Cartesian plane, i.e., points, lines, and curves arranged on virtual X, Y, and Z axes. This process creates a design easily interpreted by robotic CAM hardware including CNC machines, 3D printers, and plotters. At Hungry Knife we use Adobe Illustrator for vector design. Inkscape is a good, free alternative.

When the vector design is completed in Illustrator, it’s imported into another computer app (CAM software); Vectric Vcarve Pro. Although it includes basic design tools, I mostly use this app to assign parametric data to the geometry. This is where I program the robot; how and where to cut, what cutting tools to use, tool rpm, movement speed, plus much more. Any misstep in this process often results in ruined silver, a shattered tool, or both. When all is complete and double-checked, this data gets compiled and sent to the robot as a “part file”.

Step 3, Machining
Bring the robot online. The work quality of step 2 will determine riches or ruin. Load part files and change cutting tools, at this phase, the job is robot service and supervision. It can take 30-60 minutes to machine a 30 mm pendant. Although the robot spins the cutting tool at 18,000 rpm (pretty heckin’ fast), it moves around the piece slowly (3-8 inches per minute) to ensure nice cuts and avoid tool breakage. Our robot has a compressed air coolant system that blows a mist of isopropyl alcohol onto the tool while it cuts. This greatly reduces heat production while spinning carbide steel into sterling silver at high speeds.

Step 4, Finishing
Once the robot has done its thing, traditional benchwork begins. Initial rough finishing is done with small diamond files, very fine sandpaper, and rotary tools with slightly abrasive wheels. The robot leaves behind tiny burrs of silver so most of this work is done under magnification. To add contrast we apply dark color with an acid dip or careful application of thermoset polymer. After adding color the whole piece is aggressively polished to bring back contrast and shine lost during the coloring process.

A narrow angle photo of Patty Sparger's workbench at the Hungry Knife studio. The image features a variety of jewelers finishing tools.

Step 5, Presentation
Finishing sounds like the end of the process but this pendant could be a gift. A gift isn’t complete until it’s ready for presentation, so there’s more work yet to be done. Sometimes gifts are called presents, but in the age of e-commerce, a present requires a stylish package that can withstand the rigors of shipping and bring joy upon arrival. We carefully package each piece of Hungry Knife jewelry in a handsome gift box, attached to a branded card so it won’t jostle around in shipping. Included in each box is a special jewelry-cleaning cloth and care instruction leaflet.

Photo of a Hungry Knife Pendant Necklace packaged in a gift box. Lying next to the open box  is a care instruction leaflet and jewelry cleaning cloth which are included with every Hungry Knife jewelry purchase.

At Hungry Knife, each jewelry piece we ship is special. Whether you need a personal gift message or a custom-designed keepsake, we can help. We’ve been doing custom gifts for decades!

Send your idea or request via our Contact page to begin crafting a perfect custom gift, or shop our catalog for in-stock treasures ready to ship today.