Jewelry making has always been a traditional process, supported by different technological advances. To date, no technological advance has had as much impact on the jewelry industry as 3D printing or additive manufacturing.

With the arrival of contemporary jewelry, experimentation and innovation take center stage, and the range of materials used in the manufacture of jewelry increases considerably; not only noble metals and precious stones are valid. Materials such as plastics or fabrics begin to be used, integrating into
metal parts or being used as main materials.

JEWELRY MODELING: CAD-CAM PROGRAMS

3D printing in the world of jewelry enables many of the limitations inherent in traditional design and manufacturing processes to be overcome.

To manufacture a piece of jewelry using 3D printing, it must be previously modeled with CAD-CAM programs. Any 3D design program can be used, although there are currently specific programs for jewelry, such as RhinoJewel, RhinoGold or MatrixGold. These programs have certain options that greatly speed up the jewelry design process: predesigned gemstones and closure systems, settings and rails with adjustable parameters, etc.

An example of jewelry design and manufacturing with 3D printing technologies is the Nervous System. This company, founded in 2007, is a generative jewelry design studio that works at the intersection of science, art and technology. On its website, the user can design their own jewelry based on the modification of different parameters and buy them printed in 3D on nylon or metal.

Image 1. Nervous System design platform interface. Source: Nervous System.

3D PRINTING TECHNOLOGIES USED IN JEWELRY

After 3D modeling of the jewel, it must be 3D printed. The most used 3D printing technologies in the field of jewelry are the following:

SLA - Stereolithography

The parts resulting from 3D resin printing have a high surface quality. This technology allows you to print designs that could not be done with any manual method, such as wax casting for microfusion.

The arrival of desktop 3D printers like FormLabs has been a true revolution in the jewelery sector, due to the ease of use and the extraordinary finishes it offers.

FormLabs has developed various materials geared towards 3D jewelry printing. This, together with an affordable price, has meant that many schools, workshops and jewelry factories can afford to work with these machines.

Currently there are many types of resins for 3D printing with SLA technology. The FormLabs resins catalog should include:

• Castable resin. Developed with the perfect qualities for lost wax casting or casting.
• Castable Wax. Due to the high demand for Castable Resin, FormLabs has developed this material for the most demanding users. This resin contains 20% wax, which ensures a residue-free casting, perfect for achieving optimal results, being able to create highly detailed jewelry elements.
• Black Standard Resin. Developed for very small parts or with intricate details. This resin is very useful to create final pieces or prototypes of jewelry.

Video 1: 3D printed jewellery: Golden Century Casting. Source: Formlabs.

Both Castable Resin and Castable Wax are materials geared towards microfusion or lost wax casting. This is the oldest foundry process known, and it enables metal replicas to be obtained by means of a mold made from a prototype traditionally modeled in wax. Normally a metal model is used that serves as a matrix. From this matrix, a rubber mold is manufactured, which is filled with wax to obtain exact replicas of the matrix piece.

It is at this point that the use of FormLabs castable resins stands out, since they allow 3D models to be printed in 3D quickly and with extreme precision. Thus, the need to create the die, the mold, and the mold filling process to obtain replicas of the initial part is eliminated. This results in a significant reduction in costs and production times.

These replicas in wax or castable resin are placed inside a tubular container, which is filled with plaster. Next, it is introduced into an oven, and the wax or castable resin is melted; resulting in the mold that is filled with metal to obtain the final metal parts.

SLS Y DMLS - Selective laser sintering

Two types of selective laser sintering technologies could be distinguished: plastic 3D SLS printing and metal DMLS 3D printing.

SLS printers mainly use polyamide powder, a material widely used at an industrial level for its good mechanical properties and durability. In addition to polyamide, they can also print with elastic materials such as TPE and TPU.

The Polish company Sinterit has developed the first desktop SLS 3D printer. Sinterit currently offers two 3D printer models: Lisa and Lisa Pro, both with the same industrial 3d printing quality. Lisa is focused on those users who are starting out in 3D SLS printing, while Lisa Pro is the ideal 3D printer for those more demanding users who require higher printing volumes or a greater variety of materials. In addition to printers, Sinterit offers multiple accessories intended to simplify the preprocessing and postprocessing stages, or Sinterit Studio, a complete and simple software.

Lynne Maclachlan is an English jewelery designer who uses this technology to manufacture her designs. This designer manufactures her jewelry in polyamide and subsequently dyes them manually in colors, obtaining very striking final pieces, both in shape and color.

Image 2. Helix earrings by Lynne Maclachlan. Source: Lynne Maclachlan.

Metal SLS or DMLS 3D printing on precious metals is one of the most important innovations for the jewelery sector. This is due to the considerable simplification of the manufacturing process involved: 3D DMLS printing enables direct fabrication of a metal design. Thus, costs and manufacturing times are reduced. Today there are already 3D DMLS printers with the ability to print on precious metals.

FDM - Fused Deposition Modeling

Perhaps this is the least widely used 3D printing technology in the jewelry field. This is because with this technology you cannot carry out very complex, intricate or reduced-size designs satisfactorily.

However, depending on the part to be manufactured, 3D FDM printing technology can be very useful in the field of jewelry.
Currently there is a wide variety of filaments for 3D FDM printing, among which you can find different materials, colors and finishes.

As an example of the use of this technology in jewelry making, we would like to highlight the work of Comme des Machines; a study of sustainable and personalized manufacturing through 3D printing. Comme des Machines collaborates with jewelry designer Helena Rohner and, recently, has also collaborated with Mango, designing a collection of 3D printed jewelry.

Image 3. 3D printed pieces and pending collaboration between Comme des Machines and Helena Rohner. Source: Helena Rohner.

In addition to the options offered by materials such as PLA, thanks to filaments such as Polycast from Polymaker, you can easily print parts intended for microfusion or lost wax casting. PolyCast printed parts can be post-processed with the Polysher machine; with which a smooth and shiny finish is achieved, guaranteeing the quality of the resulting metal pieces.

Image 4. Manufacturing process with part printed with PolyCast. Source: PolyMaker.

Without any doubt, 3D printing offers different options and solutions geared towards the jewelery sector. Thus, CAD-CAM design and manufacturing using 3D printing in the jewelery sector:

• They allow the materialization of designs that would be impossible to carry out through other processes.
• They ensure the replicability of the design with great precision and accuracy.
• They simplify the design modification processes, making the development of variants feasible quickly and effectively (ring sizes, personalized products, etc.).
• Thanks to photorealistic rendering, designs and variants can be shown to the customer without having to produce the part. This option is also very useful for creating product portfolios or catalogs.
• On many occasions, they simplify the manufacturing process; welding and other steps of the manufacturing process can be avoided.

It is for all these reasons that 3D modeling and printing have carved out a niche for themselves in the jewelry sector, and more and more companies are implementing these technologies in their jewelery design and manufacturing processes.