CAD Jewelry Design Software and Process

CAD Jewelry Design Software and Process - HOLYCOME

Computer-aided design has rewritten the economics of jewelry making. A generation ago, a designer spent weeks carving wax by hand for a single ring; today, a skilled CAD artist can produce a fully measurable 3D model in a day and print a wax the same evening. Yet CAD jewelry design is not simply drawing on a computer. It is a specialized discipline with its own software, file formats, and casting constraints, and the quality of the CAD file determines the quality of everything downstream. This guide explains what happens inside a modern atelier's CAD room.

At HOLYCOME, CAD sits at the front of our production line. Every piece we manufacture, whether a bespoke engagement ring for a private customer or a private-label collection for a boutique, starts as a digital model. The model is where wall thickness, stone seats, and undercuts are decided; once it is approved and printed, those decisions are locked into metal. Getting the CAD right saves days of rework later, and getting it wrong can waste a whole casting tree. We treat the CAD room as the most important prevention point in the factory.

What Jewelry CAD Software Actually Does

General-purpose 3D software is poorly suited to jewelry. A chair or a gear does not need to hold a half-carat diamond at a specific angle, survive a 1,100-degree centrifuge casting, or be polished without breaking. Jewelry-specific CAD packages are built around those constraints: they include libraries of standard stone shapes and dimensions, automatic stone-seat generation, wall-thickness checks, and tools that flag undercuts before a piece goes to print. The designer works in millimeters, and every dimension is tied to a real stone size or a real ring size.

The output of the software is an STL or 3MF file, a mesh description of the solid model. That file is sent to a resin 3D printer, which builds the wax layer by layer in a photopolymer resin. The resolution of modern printers is fine enough that printed waxes cast into clean castings with very little cleanup. This is why CAD has almost entirely replaced hand-carved wax for production work, even in high-end houses that still market their pieces as hand-finished.

The software also stores design intent. A parametric model lets a designer change a ring size by editing one number, and the whole band, head, and stone seats update proportionally. This is how we deliver the same design across sizes four through twelve with consistent styling. Without parametric design, each size would be a separate modeling project, which would make sized collections uneconomical. This single feature is why private-label brands can offer full size runs without paying for a new design every size.

The Workflow From Brief to Approved Model

A CAD job begins with a production brief. The designer receives sketches, reference photos, the exact dimensions of any loose stones, the target ring size, and the chosen metal. From those inputs they build the model in layers: first the ring shank and basic geometry, then the setting structure, then the stone seats, then any engraving or texture details. After each major step, the model is reviewed against the brief, and the account team checks in with the customer before the next layer is committed.

Once the model is complete, the designer exports rendered images from several angles and sends them to the customer or account team for approval. For complex pieces, we also export a short turntable video so the client can see how light travels through the setting. Approval on a render is fast and cheap; approval on a printed wax, printed and shipped, adds two or three days. We encourage customers to request changes at the render stage, because modifying a file is far cheaper than reprinting and because render reviews catch the bulk of misunderstandings.

Revision discipline matters. We include two or three render revisions in our custom quotes, and after that we charge a modest hourly rate. This is not punitive; it exists because endless on-screen tweaks delay production without improving the final piece. A good CAD designer can tell a client when a requested change will not show up in metal, and pushing back politely is part of the job. The client gets a better result, and the atelier keeps the schedule honest.

How a CAD Model Becomes a Castable Wax

The approved STL file is imported into print-preparation software. The technician rotates the model to minimize supports, estimates the wax volume, and adds small sprue channels that will later carry metal into the piece. The printer then builds the wax upside down in a bath of liquid resin, curing one thin layer at a time under ultraviolet light. A typical ring takes four to eight hours to print, and a build plate can hold several dozen waxes at once, which is why batch printing is so efficient.

After printing, the wax is washed in alcohol, cured under UV light, and inspected for supports or missing features. If the wax looks correct, it is either sent to the customer as a physical prototype or attached directly to a casting tree. The link between CAD and casting is covered in detail in our lost wax casting guide; the important point here is that the CAD file must already encode every sprue and vent, because the caster cannot add geometry that the designer did not leave room for.

Printed waxes differ from carved waxes in one important way: they carry faint layer lines. Those lines reproduce on the casting as subtle texture, which is fine for most designs but shows up on high-polish platinum pieces. For those, a wax finisher hand-burnishes the layer lines before the wax goes on the tree. This is a small but real hand step that survives in an otherwise digital process, and it is one reason a print alone is not always the final word.

Task	Typical CAD time	Notes
Simple solitaire ring	3 - 5 hours	Standard shank, one stone seat
Halo engagement ring	8 - 14 hours	Circles of melee seats to align
Pavé wedding band	1 - 2 days	Dozens of micro seats, continuous fit
Statement pendant with chain	1 - 2 days	Bail geometry, hidden bail mechanics
Bespoke sculptural piece	3 - 5 days	Organic forms, multiple revisions

Why Wall Thickness and Stone Seats Matter

The most common CAD mistake is making the model look right but cast wrong. A wall that is too thin will crack during casting or bend in wear; a wall that is too thick will consume excessive gold and make the ring feel clumsy. Standard practice in our atelier is a minimum 0.4 to 0.6 millimeter wall on a ring shank, with thicker sections near the setting head where prongs take stress. The CAD software can measure wall thickness automatically, and our senior designers review every model before it leaves the screen.

Stone seats are equally critical. A seat cut too shallow leaves the stone sitting too high and vulnerable to knocks; a seat too deep hides the crown and kills the stone's brilliance. CAD libraries store measured seat depths for every standard diamond shape and millimeter size, but the designer still has to align the culet so it does not punch through the back of the setting. When we later compare diamond setting types, remember that the CAD stage is where those seats are pre-cut into the model, which is why CAD-set stones sit more consistently than hand-drilled ones.

Prong design is a related CAD decision. Four prongs give a stone more visible surface but bend more easily; six prongs are more secure but cover more of the crown. A CAD designer can simulate both and show the client renders of each. We also model prong tip size: a prong that is too thick looks heavy on a small stone, while one that is too thin wears down within a few years. These choices are made on screen, where they cost minutes, rather than after casting, where they cost weeks.

CAD Versus Hand Wax Carving Today

CAD has not eliminated hand carving; it has changed what hand carving is used for. A bench jeweler at our atelier still hand-carves sculptural pieces, one-of-a-kind artistic commissions, and organic forms that resist parametric modeling. For everything else, CAD wins on consistency, speed, and repeatability. If a private-label customer orders the same ring in fifty sizes and three metal colors, CAD lets us generate every size from a single master model, ensuring that a size four and a size nine share exactly the same head and setting.

Hand carving still matters for the finishing touches. Even on a CAD-printed wax, a carver may refine a filigree detail, adjust a prong shape, or texture a surface that the printer could not reproduce. The result is a hybrid: digital precision where it counts, hand skill where it shows. We discuss this balance further in our piece on handcrafted vs machine-made jewelry, where we compare what each method delivers in the hand and on the ledger.

Some buyers worry that CAD means less craftsmanship. The opposite is true in our experience. CAD removes the tedious, repetitive part of carving so the craftsperson can spend their hours on the parts that actually show: surface finish, prong tips, and proportion. The digital file also preserves the design so future repairs can be matched exactly. A hand-carved wax is gone once it is burned out; a CAD model is an archive that lets us recast a customer's ring decades later if it is lost or stolen.

Common CAD Mistakes That Show Up Later

Several errors are invisible on a render but expensive after casting. The first is undercut geometry: a model that cannot release from the investment mold will snap inside the casting flask, wasting the whole tree. The second is unsupported thin features, such as a filigree wire that melts away during the burn-out cycle. The third is mismatched stone seats: a designer who models for a 6.5 millimeter round but sets a customer-supplied stone that measures 6.3 will leave a loose, rattle-prone setting that eventually cracks a prong.

A fourth mistake is ignoring ring sizing geometry. A band that looks perfect in a size six may become too thin when stretched to a size ten, because the wall thickness effectively spreads out. Parametric software can flag this, but only if the designer sets the size range before modeling. We have had clients ask for a ring in a size twelve after approving a size six render, and the CAD file has to be rebuilt rather than simply scaled. That rebuild is avoidable if the size range is discussed at intake.

Our CAD team checks every model against a short checklist before export: wall thickness, undercut detection, seat dimensions against the actual stones, sprue placement, and a final render review. That checklist exists because we have seen each of these mistakes reach the casting room at least once. The cost of a ten-minute CAD review is trivial compared with recasting a batch of fifty rings, and it is one of the highest-return quality steps in the whole atelier.

Hardware, Printers, and the Print Farm

The CAD room cannot work without a fleet of resin printers that run almost continuously. We use digital light processing printers that cure a whole layer at once, rather than stereolithography machines that draw with a laser point. Layer heights of fifteen to thirty microns are standard for jewelry, because any taller and the layer lines become visible on high-polish pieces. Each printer holds a build plate that can carry several dozen waxes, and we run night builds so the waxes are waiting on the bench when the casters arrive in the morning.

Resin handling is its own discipline. Fresh resin is poured into the VAT, used resin is filtered and recycled, and VATs are calibrated weekly. A VAT that has degraded produces sticky waxes that deform during support removal. Printers are also sensitive to ambient temperature and dust, so the CAD room is air-conditioned and kept clean. These sound like small operational details, but a printer that drifts off calibration for a week can silently produce hundreds of slightly wrong waxes before anyone notices. We log every build, and we pull a test bar from each printer weekly to verify dimensional accuracy.

Post-processing printed waxes is another small craft. Supports are removed with a scalpel, the support nubs are smoothed with a hot knife, and the waxes are inspected under magnification. For pieces that will be high-polish, the wax finisher hand-burnishes the layer lines with a warm metal tool. This step adds perhaps ten minutes per ring, but it removes a whole category of polish work downstream. The wax finisher is a junior role in name only; they are the last person who can touch the geometry before it becomes metal.

How We Price CAD Work

Customers often ask how CAD labor is priced. For a one-off bespoke piece, the CAD work is quoted as a fixed design fee that covers modeling, two or three render revisions, and the first printed wax. For private-label collections, the design fee is per design, not per unit, so a brand ordering fifty rings of the same style pays the CAD cost once and amortizes it across the run. This is why private-label unit prices drop sharply as order quantities rise: the expensive front-end work is spread over more pieces, while the per-unit casting and setting labor stays roughly constant.

We also quote an optional on-site design service for larger clients. A senior CAD artist travels to the customer's office, sits with their design team, and iterates on renders in real time. This is most useful for seasonal collections where the brand has a clear aesthetic but needs help translating it into castable geometry. The daily rate is higher than remote work, but it compresses weeks of email revisions into a few days and often produces a stronger result. Most small brands do not need this, but it is part of how we support larger wholesale partners.

Transparent pricing also means explaining what CAD does not include. A CAD quote covers the digital model and the first wax; it does not cover stone sourcing, casting in platinum, plating, or overnight courier of the physical wax. We list those as line items so the customer can see exactly where the money goes. This level of detail is uncommon in the jewelry trade, where vague quotes are the norm, but it is the only way to avoid the misunderstandings that sour long-term manufacturing relationships.

File Management and Reproducibility

A CAD file is an asset, not a temporary working document. We archive every approved model with its version history, the production brief it came from, and the list of stones it was designed around. Years later, if a customer wants a ring recast in a different metal, or a replacement head for an existing setting, we pull the original file rather than starting over. This archive is what lets us service repeat orders exactly, even when the original designer has moved on to other work.

File naming follows a strict convention: customer code, design number, metal, and size. A mislabeled file is the start of a production disaster, so we have a second person read back the filename before a print job starts. We also export a low-resolution render alongside every archived file, so a future engineer can see what the design was supposed to look like without opening the CAD software. These practices sound bureaucratic, but they are how a small atelier scales from a handful of designs a year to a catalog of hundreds without losing track.

When a design is revised, we never overwrite the original. We create a new version number and keep the old one, because a customer who approved version two in 2024 may want another piece in 2026, and the current version four is not what they signed off on. Version control is invisible to the customer but essential for trust, and it is one of the first questions a sophisticated wholesale buyer asks when they audit a factory's systems.

Training the Next CAD Team

CAD artists do not emerge fully trained. We hire for an eye for proportion and a basic comfort with 3D software, then train them in-house. The first month is spent reproducing existing designs from our archive, matching them to measured tolerances. The second month introduces stone seats and wall thickness rules. Only after a designer can consistently produce a castable file without senior review do they take on client-facing work. This apprenticeship model takes longer than hiring an experienced freelancer, but it ensures that everyone on the team shares the same casting-aware instincts.

We also rotate CAD artists through the casting room for a week. Spending time pulling castings off the tree, seeing which models misrun and which come out clean, teaches more about design constraints than any checklist. A designer who has personally clipped a snapped filigree off a sprue will never again model a wire too thin. That cross-training is one reason our defect rate keeps falling: the people drawing the files understand what the metal goes through.

What This Means for Buyers and Brands

If you are a buyer commissioning a custom piece, ask to see the CAD render before it goes to print. A manufacturer that shows you renders is demonstrating both transparency and technical capability. If you are a brand owner considering a private-label partner, ask how many revisions are included in the CAD stage and whether they charge separately for reprints. At HOLYCOME, we include a reasonable number of render revisions in our custom quotes, because we would rather spend an hour in the CAD room than a day reworking a casting.

The takeaway is that CAD is not a shortcut around craft; it is a different kind of craft. The skill has moved from the wax knife to the mouse, but the person operating the software still has to understand metallurgy, stone physics, and how a polished ring should sit on a finger. That is the standard we hold our CAD artists to, and it is why every model that leaves our room is reviewed by a senior jeweler before it reaches the printer. The result is a production line that is fast enough for wholesale volumes and careful enough for one-of-a-kind commissions. If you want to see this in action, we welcome factory visits by appointment, and we are happy to walk prospective clients through the CAD station, the print farm, and the casting floor so you can judge the process yourself.

The history and conventions of engagement rings are outlined in the Wikipedia entry on engagement rings.

Frequently Asked Questions

How do I verify a factory before placing a bulk order?

Request a production video, business license, export records and a paid sample run. A factory that accepts a 50-piece test order is usually a real manufacturer.

What payment terms do you offer?

30% T/T deposit with the balance against the bill of lading. This protects both sides on first orders and can move to net terms after a track record.

What is your normal reject rate?

3–5% under 10x loupe inspection for cast and set pieces. Defective units are replaced free in the next shipment.

Where is the factory located?

Wuzhou, Guangxi, China—the core lab-grown and moissanite manufacturing cluster. Shipments go via Guangzhou or Shenzhen ports.

CAD Jewelry Design Software and Process