From CAD to Casting: How Custom Rings Are Made, Step by Step

How are custom rings made, and what makes a ring custom?

A custom ring is designed and made for one person, around one particular stone and one finger size. It is different from a ready-made ring, which is manufactured in a run and sized afterwards, and from a semi-custom ring, where you change details on an existing design. If you are still deciding which route fits you, our guide on whether custom or ready-made suits you sets out the trade-offs honestly.

Today most custom rings are built with a mix of digital and traditional work. The shape is modelled on a computer, printed as a precise model, cast in metal using a method that is thousands of years old, and then finished, set and polished by hand at the bench. The technology speeds up the design stage and makes it accurate to a fraction of a millimetre; the hand work is what makes the ring sit comfortably and hold its stone securely.

This page follows a ring from the first conversation to the day you collect it, and then covers the practical Australian questions most guides skip: GST and the Tourist Refund Scheme for overseas visitors, and how to insure the finished piece. For the wider picture of choosing a ring, start with our complete engagement ring buying guide, and if a trade term trips you up, our plain-English jewellery glossary explains it.

What happens before the CAD design starts?

Everything begins with the brief: a clear record of what the ring must be. A good brief covers the style you want, the metal, the finger size, how the ring will be worn day to day (an office worker and a nurse need different claw heights), whether a wedding band must sit flush beside it, and the budget. Our page on what to expect at a design consultation walks through the questions you will be asked.

The centre stone is usually chosen before any modelling, because the setting is built around it. Its shape matters as much as its size, and our overview of every diamond shape helps if you have not settled on one. A 1 carat round brilliant is roughly 6.4 mm across, but two stones of the same weight can differ by 0.1–0.2 mm in diameter and noticeably in depth. The designer needs the exact length, width and depth from the grading report, or measured with a gauge, so the seat and claws fit. Our guide on why the stone's exact millimetre measurements matter explains what goes wrong when a setting is drawn for a nominal size.

You can build around a natural diamond, a laboratory-grown diamond, a natural coloured gemstone or a lab-created gemstone such as lab-created sapphire. Each is disclosed clearly on the paperwork; our overview of lab-grown and lab-created gemstones explains how they differ from natural stones. If you are reusing a stone from family jewellery, it should be checked for chips and measured before design starts, because older cuts often have irregular proportions.

• Finger size: Australia uses letter sizes (the same system as the UK), with half sizes such as L½. Measure at the end of the day when fingers are warm, and twice.
• Lifestyle: hands-on work suggests a lower profile, a bezel or sturdier claws.
• Band partner: decide now if a straight wedding band must sit flush, because it changes the setting height.
• Budget: state it early so the designer can balance metal weight, stone size and detail.

How is a custom ring designed in CAD?

CAD (computer-aided design) is software that builds the ring as a three-dimensional model accurate to hundredths of a millimetre. Jewellery designers commonly use programs such as Rhino with jewellery plug-ins like MatrixGold. The model includes the stone at its real measurements, so the designer can check claw positions, metal thickness and how high the stone sits above the finger. Our guide to how jewellers use CAD software goes deeper into the tools.

You then receive renders: realistic images of the model from several angles, sometimes with a turntable video. Renders look polished, which can be misleading. Lighting and reflections are idealised, and claws can look thinner or thicker on screen than in your hand. Ask for the measurements to be shown on the views: band width, band thickness, claw diameter and the height from finger to table (the flat top of the stone). Our walk-through on reading a CAD render properly shows which views to request.

Most rings go through one to three rounds of revisions. Small changes, such as tapering a band or adjusting a gallery (the open metalwork under the stone), take a day or two each. Some workshops also print a cheap resin try-on model in plastic so you can see the scale on your hand before metal is involved.

• Band width: commonly about 1.8–2.5 mm for a solitaire; thinner bands look delicate but wear faster.
• Band thickness: below about 1.5 mm, a band can bend out of round over time.
• Claws: typically about 0.8–1.2 mm, depending on stone size and metal.
• Setting height: lower sits more safely; higher lets more light in and leaves room for a band.

How are CAD rings 3D printed and cast in metal?

Once you approve the design, the file is sent to a 3D printer. Jewellery printers build the model in thin layers of castable resin or wax, usually about 0.025–0.05 mm each. The printed model is an exact copy of the ring in a material that burns away cleanly. The model is enlarged very slightly in the file, because metal shrinks a little as it cools, often in the order of 1.5–2%.

Casting uses the lost-wax method. It is called that because the model is destroyed to make the mould:

• Spruing: the model is attached by thin channels (sprues) to a central wax stem. Several rings can be joined into a casting tree.
• Investing: the tree is placed in a steel flask and surrounded with investment, a fine plaster-like material. Platinum needs a special high-temperature investment.
• Burnout: the flask is heated slowly in a kiln, typically for several hours up to around 700–750°C, so the resin or wax burns out and leaves a ring-shaped cavity.
• Pouring: molten metal is forced into the cavity by vacuum or centrifugal force. Gold alloys are poured at roughly 1,000–1,100°C; platinum needs about 1,800°C or more and induction equipment.
• Divesting: the hot flask is quenched, the investment is washed away and the raw castings are cut from the tree.

A fresh casting is dull, rough and still has sprue stubs attached. It may also contain tiny gas holes called porosity. A careful workshop inspects each casting under magnification and recasts if porosity appears in a claw or a thin section, because it cannot be polished out reliably.

What happens after casting: cleanup, setting and polishing?

This is where the master jeweller's hands matter most. The casting is cleaned up: sprue stubs are cut and filed, surfaces are smoothed with files and abrasive papers, and the inside of the band is shaped for comfort. The ring is checked against the finger size on a ring mandrel (a tapered steel rod marked with sizes) and adjusted if needed.

Next comes stone setting, done under a microscope or high-power loupe. The setter cuts a seat into each claw with a burr so the girdle (the stone's outer edge) sits level and the pavilion clears the metal underneath. The claws are then pushed over the stone and shaped. A precise CAD model makes this easier, but a seat cut to the stone's real size is still made by hand; this is why a seat cut to the stone's real dimensions is so important. Fancy shapes with fragile points need claws placed to protect them, as our examples of protective settings for heart shaped diamonds show. Small stones in pavé or channel settings are set one by one.

Finally the ring is polished in stages, from coarser compounds to fine ones, and any texture or matte finish is added. White gold is usually plated with rhodium, a bright white metal, which wears over time and can be replated. The metal is stamped with its fineness, such as 750 for 18 carat gold or 950 for platinum. Australia has no compulsory assay-office hallmarking, so the stamp is applied by the maker. A final check covers stone security, symmetry, finish and size.

How are custom rings made by hand compared with CAD?

Before CAD, every custom ring was carved from a block of jeweller's wax by hand or fabricated directly from metal wire and sheet. Both methods are still used. Many workshops now combine them: a CAD model for accuracy, then hand fabrication for parts that benefit from forged or drawn metal, such as very fine claws. Our comparison of handmade and CAD-built rings covers this in more detail.

Which metals can a custom ring be made in?

The metal affects colour, durability, weight and price. Gold is always an alloy, mixed with other metals for strength and colour; the carat number tells you how much pure gold is in it out of 24 parts. Our definitions of fineness and alloy terms explain the vocabulary.

Platinum is heavy: a ring in platinum weighs roughly 1.3–1.4 times the same ring in 18 carat gold, which is part of why it costs more. Platinum also moves rather than wears away when scratched, so claws stay thick for longer.

How long does a custom ring take, and what does it cost in Australia?

Platinum, intricate pavé, hand engraving or a hard-to-find stone add time. Some stages can be compressed and some cannot: casting and setting need care, and burnout cycles take as long as they take. Our guide to which stages can safely be rushed explains where a deadline is realistic.

Cost depends on metal weight, design complexity, the number of small stones and the centre stone. As a broad guide only, a custom solitaire setting without the centre stone might be around AUD 1,500–3,500 in 18 carat gold and around AUD 2,500–5,000 in platinum, with halos and pavé adding more. The centre stone is usually the largest part of the total. If you love an existing design and want to change only a detail, semi-custom ring options can save time.

Do overseas visitors pay GST on a custom ring, and how do you insure it?

Australian prices include GST (goods and services tax) at 10%. Visitors leaving the country, and Australians travelling overseas, may be able to claim the GST back through the Tourist Refund Scheme (TRS), run by the Australian Border Force. The main conditions are:

• You spend AUD 300 or more (including GST) with one business, under one ABN, on one or more tax invoices.
• You bought the goods within 60 days of leaving Australia.
• You carry the ring with you as hand luggage or wear it, and can show it with the original tax invoice.
• You make the claim at the TRS facility in the international departure area, or lodge it through the official app first and then present it at the airport.

For a custom ring, timing matters. The 60-day window is counted from the purchase date on the tax invoice, and a ring that is paid in stages may have several invoices. Plan the final invoice date with the jeweller so it falls inside the window before your flight, and check the current rules on the Australian Border Force website before you travel. If you bring the ring back into Australia later, you may need to declare it and pay the GST that was refunded. The reverse also catches people out: a ring ordered from an overseas jeweller and shipped to Australia can attract GST at the border, and on goods valued over AUD 1,000 it is collected through an import declaration, sometimes with broker fees. Ask for the full landed cost in AUD before you commit.

While the ring is being made, it remains the jeweller's responsibility. Once you collect it, it is yours, so arrange cover from that day. Many home and contents policies include jewellery only up to a modest limit per item unless it is listed separately, often in the range of AUD 1,000–2,500, so an engagement ring usually needs to be listed as a specified item. Read your policy for limits, excesses and whether it covers loss away from home.

Insurers generally ask for a valuation for insurance: a written document describing the ring in detail (metal, stamp, weight, stone measurements and grades, report numbers) and giving a replacement value, which is what it would cost to replace with an equivalent ring at retail. Look for a valuer who is independent of the sale or clearly identified, and who is qualified, for example a member of the National Council of Jewellery Valuers. Keep the grading report, tax invoice, CAD renders and clear photographs together; they make a claim much easier. Update the valuation every few years, because metal and stone prices move. Our guide to budgeting for the whole ring includes insurance in the total cost of ownership.

How do you get a custom ring made? Step by step

1. Gather ideas and a budget. Save a few photos of rings you like and note what you like about each, then set a total budget including the stone.
2. Book the consultation. Use booking your first design meeting to prepare questions about metal, lifestyle and timing.
3. Choose and measure the stone. Confirm whether it is natural or lab-grown, and get its exact length, width and depth.
4. Review the CAD. Check every view and ask for dimensions; checking each render view shows what to look at.
5. Approve in writing. Confirm the final design, metal, size, price and collection date.
6. Plan tax and travel. If you are leaving Australia, align the final tax invoice with the 60-day TRS window.
7. Inspect at collection. Check the fit, stone security, stamp and finish under good light.
8. Insure it the same day. List it as a specified item using the valuation, invoice and grading report.