Can You 3D Print Silicone? Best Silicone 3D Printers and Alternatives

Silicone is a synthetic rubber that boasts several appealing characteristics for manufacturing. Its chemical structure is amazingly versatile, making it possible to adapt its chemical formula to fit diverse industrial applications from seals to joints, wearables, medical devices, robotic grippers, cooking utensils, thermal and electrical insulation, and more.

Most silicone products today are produced with injection molding, compression molding, or casting. With advancements in 3D printing, many people ask the question, “Can you 3D print silicone parts?” The answer is yes!

Silicone has a very high viscosity, making it difficult to 3D print with it precisely. It cannot be heated and extruded or cured with UV light like photopolymer materials. This means that 3D printing silicone has not typically been as widely available as other materials, but there’s finally an accessible solution available on the market today. There are also many 3D printing processes that offer 3D printing materials with silicone-like properties, and 3D printing can also be used to create molds for molding silicone parts, bringing many of the benefits of 3D printing to traditional silicone manufacturing methods.

In this comprehensive guide, learn about the different options for silicone 3D printing, its alternatives, and how additive manufacturing supports traditional silicone manufacturing processes.

Silicone 3D printers and their alternative solutions can be divided into three categories:

1. Direct silicone 3D printing: Silicone 3D printers that can print with 100% pure silicone materials.

2. 3D printing using materials with silicone-like properties: Common polymer 3D printing processes offer various materials with silicone-like material properties that can serve as alternatives for certain applications. 

3. Casting or molding silicone using 3D printed molds: Rapid tooling with 3D printing can bridge the gap between prototyping and mass-producing silicone parts with traditional manufacturing methods.

While most 3D printing technologies have been around for many years or even decades, silicone 3D printers have long remained a relatively experimental field due to the complexity of printing with silicone. Over the last few years, some companies have brought silicone 3D printers to the market, but these solutions all had certain limitations alongside excessively high costs (over $100,000), which means that they were not suitable for most businesses and applications. 

In 2023, Formlabs introduced the Silicone 40A Resin, the first accessible 100% pure silicone 3D printing material, made possible by the patent-pending Pure Silicone Technology™, which combines the outstanding material properties of cast silicone and the benefits of 3D printing. 

The solution relies on the accessible (starting at $2499) and versatile (over 45 additional advanced materials) Form 3+ stereolithography (SLA) 3D printing ecosystem, to produce 100% silicone parts in-house, in a matter of hours.

Silicone 40A Resin parts, with 40A Shore durometer, 230% elongation at break, and 12 kN/m tear strength, are ideal for applications requiring pliability and durability even through repeated stretching, flexing, or compression. Parts made with Silicone 40A Resin have a rebound resilience of 34%, excellent chemical and thermal resistance (-25°C to 125°C), and can have fine features as small as 0.3 mm and complex shapes that are challenging to achieve with traditional manufacturing methods.

Silicone 40A Resin parts are ideal for the following applications: 

• Rapid prototyping, beta testing, and validation stages of the product development cycle for elastic consumer goods, automotive components, and industrial equipment such as connectors, grommets, actuators, keypads, and watch bands.
• Cost-efficient low-volume or custom manufacturing of indoor end-use parts, such as seals and gaskets.
• High-quality, long-lasting custom manufacturing aids and tools such as flexible casting molds, jigs, fixtures, and masking tooling.
• Medical device components, patient-matched prosthetics, and audiology applications.
• Complex geometry parts that are difficult to manufacture with traditional methods.

The product development team at FINIS, Inc. 3D printed swimming goggle gaskets similar to production quality within a mere eight hours for just $10 a piece, significantly undercutting the usual expenditure of over $1,000 and a three-week timeline associated with outsourced urethane casting. The 3D printed silicone gaskets underwent rigorous water tightness assessments within a swimming pool environment, helping the team shorten their product development schedule.

Dorman Products, a century-old manufacturer of aftermarket automotive parts, has turned to silicone 3D printing to produce custom gaskets for pressure testing new products. Previously they’d cut the gaskets using the metal dies in an arbor press, but switching to 3D printing allowed the team to drastically reduce lead times and costs, especially considering that they had to test hundreds of new components.

HGM Automotive Electronics is a specialty transmission controller manufacturer that, through rigorous chemical and mechanical testing, demonstrated that the parts printed in Silicone 40A Resin have excellent mechanical properties and chemical resistance, similar to injection molded silicones that they have traditionally relied on. After six weeks of thermal cycling in an engine bay under normal operating conditions and additional chemical fluid exposure tests, they have qualified 3D printed Silicone 40A Resin parts for end-use automotive parts.

Some of the primary reasons why manufacturers choose silicones are the elasticity and flexibility of these materials that empower a wide range of applications. 

Silicones generally fall between 10A and 80A Shore durometer hardness. Common polymer 3D printing processes like fused deposition modeling (FDM), stereolithography (SLA), and selective laser sintering (SLS) offer various materials in this hardness range, with various degrees of likeness in other important material properties of silicone such as durability, thermal stability, UV resistance, food safety, biocompatibility, as well as color and translucency options.

For FDM 3D printing, elastomers such as thermoplastic polyurethane (TPU) and thermoplastic elastomer (TPE) are the most flexible materials that can offer an alternative to silicone. These materials are commercially available at Shore 45A to Shore 90A hardness, which covers the harder end of the silicone hardness range.

The pros associated with these alternatives are the general affordability of FDM 3D printers and materials. Conversely, the cons include lower precision and dimensional accuracy, low resolution, quality, and part strength, and limited design freedom that all restrict real-world usability. Silicone-like FDM materials are generally less durable than standard silicone, not food-safe, have lower temperature resistance, and offer limited color and no real translucency options, but they can be biocompatible and skin-safe.

Stereolithography 3D printing is popular among professionals for its high precision and wide range of material options. SLA 3D printing offers multiple alternatives to silicone that empower manufacturers to prototype silicone-like parts or even manufacture end-use parts with the flexibility, elasticity, and durability of silicone. SLA parts offer the smoothest surface finish and greater design freedom than FDM.

Silicone-like flexible 3D printing resins are generally also less durable than standard silicone, not food-safe, not biocompatible (but can be skin-safe), and have lower temperature resistance. Silicone-like SLA materials can be translucent and can also be dyed to different colors.

The specific material availability is dependent on the printer model, but generally falls within the 30A and 90A Shore durometer hardness range. Alternative materials to silicone among Formlabs’ SLA 3D printing materials include:

• Elastic 50A Resin is a soft material that’s suitable for prototyping parts normally produced with silicone. This 50A Shore material is ideal for parts that will bend, stretch, compress, and hold up to repeated cycles without tearing, and spring back quickly to their original shape. Choose Elastic 50A Resin for applications like wearables (straps), stretchable enclosures and casings, compressible buttons, or soft tissue anatomy models in healthcare.

• Flexible 80A Resin is a stiff soft-touch material with an 80A Shore durometer to simulate the flexibility of hard silicones, as well as rubber or TPU. Balancing softness with strength, Flexible 80A Resin can withstand bending, flexing, and compression, even through repeated cycles. It is ideal for prototyping applications like handles, grips, overmolds, cushioning, damping, shock absorptions, seals, gaskets, and masks, or cartilage, tendon, and ligament anatomy models in healthcare.

• While slightly beyond the hardness range of silicone materials, Rebound Resin is an 86A Shore elastic 3D printing material that offers unique properties for end-use applications. With five times the tear strength, three times the tensile strength, and two times the elongation of other production-grade elastomeric materials on the market, Rebound Resin is perfect for 3D printing springy, resilient parts. Rebound Resin’s high elongation makes it perfect for tactile, stretchy parts such as handles and grips. It is strong enough to handle constant compression or tension, which is ideal for manufacturing complex gaskets and seals that last.

Selective laser sintering (SLS) 3D printing is the most common additive manufacturing technology for industrial applications. It offers high accuracy, high throughput, and almost limitless design freedom as the unfused powder supports the part during printing and eliminates the need for dedicated support structures.

SLS materials with silicone-like properties include TPU, TPE, and TPA, offering hardness ranges between 45A and 90A Shore. The exact availability is dependent on the printer model.

For Formlabs Fuse Series SLS 3D printers, TPU 90A Powder is a tough elastomer for producing resilient products with unmatched design freedom and ease. Balancing high elongation at break and superior tear strength, TPU 90A Powder enables you to produce flexible, skin-safe prototypes and end-use parts that withstand the demands of everyday use – all at a low cost per part. TPU 90A Powder is ideal for prototyping as well as end use part production of wearables, soft-touch elements, padding, dampers, grippers, gaskets, seals, soles, splints, orthotics, prosthetics, and more.

Parts produced with silicone-like SLS materials are accurate, durable, abrasion and wear-resistant, and have the highest temperature resistance of the three plastic 3D printing processes. They can be biocompatible, skin-safe, and also food-safe after post-processing. On the downside, SLS printing offers limited color and no translucency options, and designs with thin walls may warp while cooling down.

For those looking to produce pure silicone parts with unique properties (different hardnesses, colors, etc.), 3D printing can also help bridge the gap between prototyping and mass-producing silicone parts with traditional manufacturing methods.

Injection molding, thermoforming, compression molding, and silicone casting all make use of molds to create the finished silicone product. However, tooling comes with high upfront costs and weeks or months-long lead times from service providers, slowing down product development and extending the time it takes to get a product to market.

Incorporating in-house rapid tooling into the product development process empowers businesses to validate the design and material choice before transitioning to mass production and provides an affordable means to produce custom or limited series of end-use parts.

Google’s Advanced Technology and Projects (ATAP) team used 3D printed stand-ins or surrogate parts instead of overmolded electronic sub-assemblies for the initial tool tuning at the factory. They were able to cut costs by more than $100,000 and shorten their testing cycle from three weeks to just three days using a combination of 3D printing and insert molding. Google ATAP’s team found that by 3D printing test parts, they could save time and money over using expensive electronic parts that had to be shipped in from a supplier.

Dame Products, a Brooklyn-based startup, designs products for the health and wellness industry. They employ silicone insert molding to encapsulate internal hardware for customer beta prototypes. The Dame Products product line incorporates complex ergonomic geometries fully encapsulated in a layer of skin-safe silicone in vibrant colors.

Silicone insert molding is also ideal for manufacturing low volumes of end-use parts. Advanced prosthetics manufacturer Psyonic uses the process to create fingers for prosthetic hands that have a hard 3D printed core overmolded with silicone, while Robotics manufacturer RightHand Robotics uses the same process to create grippers for robots.

3D printed rapid tooling for compression molding can be leveraged for the production of thermoplastic, silicone, rubber, and composite parts. Product developers at kitchen appliance manufacturer OXO use 3D printing for prototyping rubbery components such as gaskets by compression molding two-part silicone using 3D printed molds.

Casting is also a popular method for producing silicone and plastic parts for medical devices, audiology, food-safe applications, and more.

Medical device company Cosm manufactures patient-specific pessaries for patients with pelvic floor disorders. They 3D print molds on an SLA 3D printer and inject biocompatible, medical-grade silicone into it to create the part. Rapid tooling with 3D printing allows them to create custom parts without the high costs of traditional tooling.

Manufacturing custom ear molds with 3D printing has also revolutionized the audiology space, for applications like hearing aids, noise protection, and custom-fit earphones. Digital manufacturing provides greater control and accuracy compared to traditional mold production, significantly reducing the number of errors and remakes.

Silicone casting is also used in the entertainment industry. Jaco Snyman, founder of the award-winning practical prosthetic make-up effects and prop-making company Dreamsmith Studio, used a variety of these techniques for the sci-fi series “Raised by Wolves”. Leveraging the large build volume of the Form 3L large-format resin 3D printer, Snyman created a hyper-realistic silicone replica of an actress’s body, silicone masks for actors, human-size dummies, and more.

Conversely, silicone materials can also be used to create molds for molding various materials. Read our guide to learn how to make silicone molds.

Direct silicone 3D printing is now finally easily accessible and there are many other ways to leverage the benefits of 3D printing to produce silicone or silicone-like parts.

Request a free sample part printed in Silicone 40A Resin or Formlabs’ flexible and elastic SLA materials or speak with a 3D printing expert today to find the right solution for your application.

Request a free sample of our flexible and elastic SLA materials or speak with a 3D printing expert today to find the right solution for your application.