
La goma de silicona es un material versátil con propiedades mecánicas, como la resistencia al calor y la biocompatibilidad, que lo hacen muy adecuado para aplicaciones en el campo de la medicina. Usos como audífonos personalizados, asas y mangos especializados para productos sanitarios, modelos anatómicos blandos y prótesis convierten a la silicona en un material clave para el sector sanitario.
En esta guía, describiremos las formas de las que se puede usar el ecosistema de Formlabs para crear piezas de verdadera silicona para la sanidad. Para conocer el proceso de trabajo completo tanto para imprimir con la Silicone 40A Resin como para moldear silicona utilizando impresoras 3D de estereolitografía (SLA) de Formlabs, descarga nuestro libro blanco.

Habla con nuestros expertos
Independientemente de si lo que necesitas es fabricar herramientas quirúrgicas adaptadas a los pacientes o crear prototipos para un producto sanitario cardíaco, nosotros estamos aquí para ayudarte. El equipo Formlabs Medical es un grupo de especialistas que saben exactamente cómo ofrecer la asistencia que tu negocio y tú necesitáis.
Producción de piezas de silicona
Las piezas blandas y gomosas tienen usos sanitarios, que abarcan desde modelos anatómicos blandos hasta prótesis y otros dispositivos ponibles. Los diseñadores pueden incorporar a sus catálogos piezas de verdadera silicona robustas, flexibles y estirables mediante dos métodos: la impresión directa con la Silicone 40A Resin y el moldeo de silicona usando herramientas impresas en 3D mediante SLA.
La silicona es un material muy utilizado para fabricar productos sanitarios blandos de uso final. También se puede usar para fabricar moldes blandos para la fundición de materiales rígidos, un proceso conocido como "fabricación de moldes de silicona". Esta guía solo trata la producción de piezas de silicona, que crea piezas blandas y gomosas imprimiendo directamente con la SIlicone 40A Resin o fundiendo silicona en moldes impresos en 3D. En nuestra guía, encontrarás más información sobre la producción de piezas rígidas mediante la fabricación de moldes de silicona.
Nuestro libro blanco incluye ejemplos de producción de piezas de silicona con distintos métodos. Algunos ejemplos son los siguientes:
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Impresión directa de silicona: Las piezas de silicona se producen directamente en impresoras 3D de resina Form 3/B/+ con la Silicone 40A Resin. Este método es el mejor para producir geometrías complejas que no se pueden obtener mediante el moldeo.
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Moldeo por compresión de masilla de silicona: Una silicona de curado rápido se coloca en dos lados de un molde impreso en 3D, que se sujeta con un tornillo de banco. Este método a menudo se usa para prototipos de juntas e imita las herramientas utilizadas en la producción en masa.
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Molde llenado por inyección para silicona líquida: Este es el método más común para moldear un prototipo único continuo de silicona, utilizando un molde en dos o más piezas. En muchos casos, el molde está configurado de manera que la gravedad contribuye al proceso de llenado de silicona. La silicona se inyecta en un canal en la parte superior del molde y la cavidad del mismo se va llenando lentamente desde la parte inferior. Por último, la silicona líquida se libera mediante salidas y canales de aire en la parte superior del molde.
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Sobremoldes para el encapsulado total o parcial de hardware en silicona: El hardware se suspende en un molde de dos o más piezas. A continuación, se inyecta silicona líquida en la cavidad del molde, para que envuelva total o parcialmente el hardware.
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Moldes de cascarón para productos de silicona personalizados: El molde es un cascarón delgado (de menos de 1 mm) que envuelve la cavidad de inyección de silicona. Una vez que la silicona está curada, el cascarón impreso en 3D se rompe para revelar una pieza de silicona. Dado que este es un molde sacrificable que no se puede reutilizar, esta técnica se usa para crear una única pieza personalizada. Una guía paso a paso sobre la producción de moldes de cascarón se describe con gran detalle aquí en relación con los moldes auriculares de silicona.
Los métodos de diseño, impresión y fundición comparten pasos fundamentales incluso entre diferentes sectores y aplicaciones. Para ver un ejemplo de diseño detallado de un sobremolde llenado por inyección, que tiene en cuenta los consejos y las buenas prácticas que ofrecen nuestros clientes, lee el libro blanco completo.
Tipos de siliconas
Las siliconas son un tipo de polímeros que contienen los elementos químicos del silicio y el oxígeno en su cadena molecular, y que pasan de un estado de gel o líquido a un estado sólido muy flexible y estirable después del curado. Son materiales versátiles con propiedades de alto rendimiento, como un excelente aislamiento eléctrico, resistencia al calor, estabilidad química, una gran resistencia al desgarro y biocompatibilidad, lo que las hace atractivas para sectores muy exigentes, como el de la sanidad.
Los elastómeros de silicona dominan el mercado y se pueden dividir en tres categorías:
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Las gomas de silicona líquidas son siliconas de alto rendimiento que se suelen emplear para producir piezas técnicas resistentes con tolerancias ajustadas, como sellos o conectores electrónicos. Se procesan a temperaturas elevadas, a menudo mediante el moldeo por inyección de líquido, y se eligen para una producción de gran volumen.
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Las siliconas vulcanizadas a alta temperatura (HTV), también llamadas gomas de silicona curadas por calor, ofrecen una buena resistencia a las temperaturas elevadas y al envejecimiento, lo que resulta ideal para cables o aislantes en productos sanitarios. Suelen utilizar una química catalizada con platino y se les da forma mediante extrusión o moldeo por compresión, con una vulcanización bajo presión y calor. Descubre cómo los expertos en silicona de SiOCAST dan forma moldes de silicona vulcanizada a alta temperatura alrededor de patrones maestros impresos en 3D.
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Las siliconas vulcanizadas a temperatura ambiente (RTV) son relativamente más fáciles de procesar, con buenas propiedades mecánicas y térmicas para juntas y productos sanitarios, así como para el encapsulado de componentes eléctricos y la fabricación de moldes. Tradicionalmente, se les ha dado forma a temperatura ambiente, mediante moldeo por inyección, moldeo por compresión o fundición por gravedad.
Este informe recoge el uso de las siliconas vulcanizadas a temperatura ambiente (RTV). Describe técnicas que se pueden utilizar in situ en cualquier laboratorio de prototipado o de desarrollo de productos. Algunas formas específicas de siliconas RTV son:
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Silicone 40A Resin: La Silicone 40A Resin es una resina de silicona de un componente que produce piezas 100 % de silicona con una elasticidad, resistencia química y estabilidad térmica excelentes. Las piezas se imprimen directamente en la Form 3/3B y se posacaban con una mezcla de alcohol isopropílico (2-propanol) y acetato de n-butilo, y luego con agua, calor y luz UV.
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Silicona líquida vulcanizada a temperatura ambiente: Las siliconas líquidas suelen estar formadas por dos componentes o por un componente con una pequeña cantidad de catalizador añadida. Existen dos categorías generales que se pueden obtener fácilmente. Las siliconas catalizadas con platino son más costosas, pero ofrecen una mejor estabilidad dimensional a largo plazo y un grado de contracción muy bajo tras un curado completo. Las siliconas catalizadas con estaño son más económicas, pero ofrecen una menor estabilidad a largo plazo y suelen contraerse más. El tiempo de curado varía de 10 minutos a varias horas.
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Polidimetilsiloxano (PDMS): El PDMS es un tipo químicamente distintivo de silicona líquida RTV que contiene grupos metilo en la cadena polimérica de silicio y oxígeno. El polímero líquido se utiliza mucho como lubricante o aditivo modulador de la viscosidad en productos industriales y de consumo. Como goma curada, el PDMS se utiliza en varias aplicaciones de investigación. Su gran transparencia óptica y su capacidad de capturar texturas y canales microscópicos de las superficies hacen que sea ideal para la microfluídica y la litografía blanda. Muchas fórmulas de PDMS se curan a temperatura ambiente durante un período de 48 horas o en menos de una hora si se someten a temperaturas elevadas.
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Masilla de silicona: Se trata de una masilla de dos componentes que se mezclan a mano en volúmenes equivalentes. El tipo que aparece en este informe tiene una dureza Shore de 40A (véase la escala que aparece a continuación) o, en otras palabras, una dureza parecida a la de una goma de borrar. Este tipo de silicona se puede adquirir de proveedores de joyería, ya que se suele utilizar para producir moldes maestros de cera para la fundición de metal. Sin embargo, la misma silicona también es un buen imitador para juntas y sellos moldeados por compresión.
Contacto seguro con la piel, las membranas mucosas o los alimentos
Algunas aplicaciones requieren más sensibilidad que otras cuando entran en contacto con el cuerpo o con la comida. Consulta siempre las fichas de datos de seguridad de los materiales (FDS) del fabricante de la silicona para asegurarte de que el material se pueda utilizar con seguridad para tu aplicación. Ten en cuenta que las siliconas líquidas de dos componentes que están aprobadas para el contacto con la piel tienden a usar un catalizador de platino.
La Silicone 40A Resin se está evaluando actualmente como un producto en contacto con la piel de conformidad con la Norma ISO 10993-1 para los siguientes parámetros de biocompatibilidad: ISO 10993-5:2009, 10993-23-2021:2021, ISO 10993-10:2021.
Escala de dureza
Los materiales elásticos, incluidas las gomas de silicona, pueden ofrecer distintos grados de dureza, desde extremadamente blandos a extremadamente firmes. El número de dureza Shore es el que expresa esa característica. La escala Shore A mide los materiales más blandos, mientras que la escala Shore D recoge los materiales más duros. La tabla que se muestra a continuación ofrece una comparación útil para productos comunes del hogar.

¿Imprimir o moldear?
Los requisitos específicos de la aplicación que darás a tus piezas y tu proceso de trabajo determinarán si el método óptimo es la impresión directa o el moldeo con silicona. Aquí tienes algunas especificaciones de cada proceso que tener en cuenta:
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Geometrías complejas: No todas las geometrías se pueden obtener mediante moldeo. La impresión directa es preferible para aplicaciones que requieran geometrías complejas.
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Color: La Silicone 40A Resin es de color negro. Para aplicaciones que requieran translucidez o piezas en color, el moldeo con silicona puede ser una opción preferible.
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Tiempo: Diseñar piezas para una impresión directa lleva menos tiempo que diseñar moldes. Además, el tiempo necesario para imprimir una sola pieza de silicona es considerablemente menor que el que hace falta para imprimir un molde y luego llenarlo de silicona. Cuando el tiempo es un problema, se suele preferir la impresión directa.
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Olor: La Silicona 40A Resin se termina de imprimir con un olor que puede tardar en disiparse. Este proceso puede acelerarse curando tu pieza impresa en una mezcla de agua y Febreze HD, pero el moldeo con silicona puede ser preferible para aplicaciones en las que el olor del material sea una preocupación importante.
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Biocompatibilidad: Los distintos tipos de silicona tienen diferentes niveles de biocompatibilidad. La Silicone 40A Resin se está evaluando actualmente para usarla en contacto con la piel de acuerdo con la norma ISO 10993-1. El moldeo con silicona puede ser preferible para aplicaciones que requieran niveles más exhaustivos de biocompatibilidad.
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Exposición a los rayos UV: Las propiedades mecánicas de la Silicone 40A Resin se degradarán tras una exposición repetida a la luz UV. Para aplicaciones en las que las piezas van a pasar mucho tiempo expuestas a la luz solar directa, probablemente sea preferible usar el moldeo con silicona.
Para aplicaciones médicas que requieren piezas gomosas para las que la silicona no es una buena opción, puedes considerar usar otros elastómeros de Formlabs, como la BioMed Elastic 50A Resin (en el caso de la SLA) o el TPU 90A Powder (para impresiones 3D SLS).
Material | Impresora | Resistencia a la rotura por tracción | Esfuerzo de alargamiento al 100 % | Alargamiento de rotura |
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Silicone 40A Resin de Formlabs | Form 4/B Form 3/B/+ | 7,2 MPa | 4,5 MPa | 135 % |
BioMed Elastic 50A Resin | Form 4/B Form 3/B/+ | 2,3 MPa | 1,3 MPa | 150 % |
BioMed Flex 80A Resin | Form 4/B Form 3/B/+ | 7,2 MPa | 4,5 MPa | 135 % |
TPU 90A Powder | Fuse 1+ 30W | 8,7 MPa (X/Y) 7,2 MPa (Z) | 7,2 MPa (X/Y) 7,0 MPa (Z) | 310 % (X/Y) 110 % (Z) |
Información general sobre la impresión 3D con la Silicone 40A Resin
La Silicone 40A Resin utiliza la tecnología con patente en trámite Pure Silicone Technology™ y el ecosistema de estereolitografía (SLA) de Formlabs para producir in situ piezas 100 % de silicona en cuestión de horas. Es ideal para aplicaciones que requieren flexibilidad, durabilidad y resistencia a esfuerzos repetidos de estiramiento, flexión o compresión.
Propiedad del material | Silicone 40A Resin |
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Dureza Shore | 40A |
Alargamiento de rotura | 230 % |
Resistencia al desgarro | 12 KN/m |
Resiliencia de rebote | 34 % |
Intervalo de temperaturas | -25 °C a 125 °C |
La Silicone 40A Resin se usa en ámbitos tan diversos como el prototipado rápido, las pruebas de fase beta y las etapas de validación en el desarrollo de productos, además de para llevar a cabo de forma rentable una fabricación personalizada o de bajo volumen de piezas de uso final. El material también es adecuado para la fabricación de productos sanitarios, prótesis adaptadas a los pacientes y componentes de audiología, así como para la fabricación de piezas con geometrías complejas difíciles de fabricar mediante métodos tradicionales.

La impresión 3D directa de silicona con la Silicone 40A Resin es ideal para aplicaciones como el prototipado rápido, los accesorios para la fabricación, el utillaje y la fabricación de bajo volumen o personalizada.
Empezar a usar la Silicone 40A Resin resuelve los antiguos problemas asociados a los métodos tradicionales de impresión 3D con silicona, como los costes elevados y las limitaciones técnicas. La impresión en un clic con la Silicone 40A Resin ahorra tiempo al eliminar la necesidad de diseñar y fabricar los moldes, y de verter y fundir la silicona. También abre posibilidades de diseño al permitir a los usuarios crear geometrías complejas difíciles de conseguir con los métodos de fabricación tradicionales. Esta solución accesible permite a las empresas crear piezas de uso final de alta calidad sin hacer concesiones en cuanto al precio, la calidad o la velocidad.
Información general sobre utillaje impreso en 3D para el moldeo con silicona
Los moldes tradicionales para la producción de piezas de silicona se fabrican mediante mecanizado CNC, a partir de bloques de aluminio o acero. Estos moldes tradicionales incluyen moldes de inyección de dos o más piezas para gomas de silicona líquida o moldes de compresión de cavidad única con una lámina de goma de silicona curada por calor que se cura al someterla a presión y altas temperaturas. Normalmente, estos tipos de moldes de metal se utilizan para la producción en masa. Sin embargo, cuando se emplean para el prototipado, los tiempos de entrega de varias semanas y los cientos o miles de euros que hay que invertir de antemano en herramientas limitan la capacidad de los diseñadores de aplicar y probar pequeños cambios en un diseño de molde.
La impresión 3D de escritorio es una potente solución para fabricar herramientas con rapidez y bajos costes. Requiere muy poco equipamiento, por lo que los operarios cualificados pueden centrar su atención en otras tareas importantes. Con la impresión 3D en sus propias instalaciones, los fabricantes y los diseñadores de productos pueden introducir el utillaje rápido en el proceso de desarrollo de productos para validar las decisiones de diseño y materiales antes de pasar a la producción en serie. Pueden realizar iteraciones rápidamente, acelerar el desarrollo de productos y lanzar productos mejores al mercado. El utillaje impreso en 3D utilizando las resinas para estereolitografía de Formlabs ofrece muchas ventajas a los diseñadores de productos en el prototipado, las series de producción a pequeña escala y la producción de piezas personalizadas. Mediante el utillaje impreso en 3D, las siliconas RTV de dos componentes se inyectan en un molde de dos o más piezas, o se introduce masilla de silicona RTV entre las secciones de un molde de compresión impreso en 3D. Gracias al utillaje impreso en 3D, hay un amplio abanico de siliconas catalizadas con estaño y con platino disponibles para los diseñadores, que abarcan una amplia gama de durezas, colores y grados de transparencia, así como funciones especiales como su seguridad para el contacto con la piel.

Producción de piezas de silicona con herramientas impresas en 3D
Este informe ofrece una guía paso a paso sobre el utillaje impreso en 3D para la producción de piezas de silicona, con buenas prácticas y casos de estudio de clientes.
La tecnología de impresión 3D por estereolitografía (SLA) es una buena elección para las herramientas de moldeo con silicona. Las piezas elaboradas mediante SLA se caracterizan por un acabado de la superficie liso y una alta precisión. Las gomas de silicona RTV capturan detalles precisos de la superficie, incluidos sus defectos, por lo que la calidad de la superficie de la herramienta se traduce directamente en la calidad de la superficie de la pieza final. Por ejemplo, un molde impreso con una impresora de modelado por deposición fundida (FDM) dejaría improntas visibles de las líneas de capa de la impresión en la pieza de silicona.
En cambio, la impresión 3D SLA con la BioMed Clear Resin o la Clear Resin de Formlabs permite visualizar el proceso de inyección de la silicona, con lo que los diseñadores pueden evaluar la formación de burbujas y vacíos e identificar las áreas en las que se deberían añadir filetes en las esquinas o más respiraderos de aire. La impresión 3D SLA también ofrece una ventaja en cuanto a la complejidad del diseño, ya que un molde impreso en 3D permite a los diseñadores aprovechar los socavados u otras geometrías complejas que no serían posibles o resultarían prohibitivamente caras de fabricar mediante el mecanizado CNC.

PSYONIC encapsula los dedos de la Ability Hand utilizando una configuración de sobremolde de silicona. Algunos moldes incluyen un inserto de molde de Tough 2000 Resin para anclar el "hueso" encapsulado en el molde.
La BioMed Clear Resin y la Clear Resin de Formlabs también son bastante versátiles en cuanto a su rendimiento mecánico. El mismo material se puede utilizar para crear un molde de cascarón extremadamente delgado que se quiebra y retira fácilmente de una pieza de silicona personalizada o para crear un molde de impresión robusto que se utiliza varias veces para producir juntas. Por último, llevar a cabo una fabricación asequible a escala del banco de trabajo reduce los tiempos de entrega, ya que un diseñador puede imprimir una geometría de molde y empezar a inyectar silicona el día siguiente.
Cuando se utiliza con moldes impresos en 3D, la goma de silicona vulcanizada a temperatura ambiente captura los detalles más precisos de la superficie, incluido el texto en relieve. Además, la mayoría de las siliconas para fundición no se adhieren químicamente y se pueden despegar de la superficie del molde tras el curado. Se puede conseguir una unión mecánica realizando la fundición sobre superficies muy porosas, como una tela. En algunos casos, se puede fomentar una unión química con aglutinantes especializados.
Ya que la silicona RTV no requiere temperaturas o presiones elevadas, se le puede dar forma fácilmente con un equipamiento limitado en un laboratorio de prototipado, lo que reduce el coste inicial de incorporar piezas blandas en el catálogo de diseño de cualquier empresa. Las instrucciones para fabricar piezas de silicona in situ de forma rápida y asequible en bajas cantidades se incluyen en el libro blanco completo.
Compatibility of 3D Printing Resins and Silicones
Anytime a castable material such as silicone comes into contact with a printed mold, we must consider the chemical interaction between the two materials. When casting platinum-catalyzed silicones in SLA molds, one particular challenge arises: the resin monomer can inhibit the silicone curing process, leaving an uncured gummy surface. However, high-quality platinum-catalyzed silicone parts can be produced by making sure SLA molds are fully cleaned and cured, and by applying protective coatings and mold releases.
There are many possible combinations of silicone, resin, protective coating, and mold release that you can try. We asked customers from a variety of industries to report on their successful workflows, and their responses are summarized below. We considered many of these insights when developing our own step-by-step process.
Sector | Aplicación | Tipo de molde | Silicona | Resina | Best Practices |
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Product Design | Beta prototypes Skin contact | Sobremolde | Unspecified (Pt cure) | Clear Resin | Paint on Vaseline as mold release |
Product Design | End-use | Eggshell mold | Smooth-On Mold Max (Tin cure) | Clear Resin | No mold release used; mold is sacrificial / one-time use |
Product Design | Prototypes | Compression mold | Castaldo Quick-sil (putty) | Clear Resin | General purpose mold release from Smooth-On |
Product Design | Prototypes skin contact | Injection filled mold | Unspecified (Pt cure) | LT Clear Resin Clear Resin Grey Resin | Any general purpose mold release |
Product Design | Prototypes Skin contact | Injection filled mold Overmold | Smooth-On Dragon Skin 20 (Pt cure) | Clear Resin | Krylon Crystal Clear Acrylic spray + Ease Release 200 |
Manufacturing / Healthcare | End-use | Injection filled mold Overmold | Smooth-On Dragon Skin 20 (Pt cure) | Clear Resin | No mold release needed |
Manufacturing / Healthcare | End-use Mucous membrane contact | Eggshell mold | Unspecified (Pt cure) | Biomed Amber Resin | No mold release used; mold is sacrificial / one time use |
Audiology / Healthcare | End-use Skin contact | Eggshell mold | BioPor AB 40 by Dreve | Clear Resin Biomed Clear Resin | No mold release used; mold is sacrificial / one time use |
Entretenimiento | Models and props Skin contact | Injection filled mold Open mold | Smooth-On FX Pro (Pt cure) | Black Resin >br>Grey Resin | Mold release not always needed |
Entretenimiento | Models and props Part reproduction | Open mold Silicone mold | Variety of Pt and Tin cure by Smooth-On | Crear Resin Grey Resin | XTC-3D High Performance 3D Print Coating |
Entretenimiento | Models and props Part reproduction | Silicone mold | Unspecified (Pt cure) | Cler Resin | SEM Flexible Primer Surfacer spray coating |
Entretenimiento | Models and props Skin contact | Injection filled mold | Platsil Gel-25 by Polytek (Pt cure) | Rigid 10K Resin | Smooth-On Super Seal coating and Ease Release 200 |
Hobby | art reproduction | Open mold Silicone mold | Smooth-on OOMOO 30 (Tin cure) | Grey Resin | General purpose mold release from Smooth-On |
While the combination of materials clearly varies, our customers aligned on the following:
- Make sure your parts are fully washed and cured. The 3D printed mold must be washed thoroughly in clean IPA, such that surfaces are not tacky after the mold dries. The mold should also be cured completely to reduce the amount of unreacted monomer on the SLA parts. For this process, the Form Cure is a great option. Clear Resin parts will develop a yellow tint, which is a good indicator that your mold is fully cured.
- Try a protective coating. There are many acrylic or epoxy coatings available that are applied as an aerosol spray in a single step (e.g. Krylon Crystal Clear acrylic coating), or as a two-part brush- on material (e.g. XTC-3D from Smooth-On). Using very little material, both types of coatings will leave a glossy, glass-like finish on the internal surfaces of the mold. Multiple applications may be needed. Check the manufacturer’s instructions for drying or curing times.
- Use a mold release anytime silicone contacts another material. This will ease the de-moldingstep, and eliminate silicone residue inside the mold, making it easier to reuse it for multiple castings. In many cases a generic or “general purpose” mold release from your silicone brand is sufficient (e.g. Stoner Dry film e408). A light mist of mold release is enough. Once again, check the manufacturer's instructions for recommended drying times.

Presentamos la Form 4B: Una producción más rápida, una mayor precisión y equivalencias normativas
Descubre cómo la Form 4L y la Form 4BL pueden hacer posibles nuevos niveles de productividad e innovación mediante su incomparable velocidad, precisión y fiabilidad.
Additional Best Practices
Some silicone formulas, such as PDMS, are more susceptible to cure inhibition than others when they come into contact with SLA 3D printed tooling. We have listed further troubleshooting steps provided by Formlabs users, which build off of our general guidelines for RTV liquid silicones.
- Rinse with acetone. Spraying the 3D printed mold with an acetone squeeze bottle can help to remove residual solvent and any debris after the standard IPA washing step.
- Over-cure the mold. For tooling printed in Clear Resin, increase the curing time from 15-20 minutes to 60-120 minutes at 60 °C.
- Wait 24-48 hours after post-processing. Allow the mold to sit in ambient temperature and light before applying coatings and casting the silicone. It is helpful to expose the mold surfaces to open airflow during this step.
- Use an epoxy coating. A two-part epoxy sealant can act as an effective barrier between the silicone and the 3D printed mold.
- Use a higher concentration of catalyst. When using two-part silicones, we suggest adding a bit of extra catalyst component. If a small proportion of the catalyst is inhibited by the mold surface, the extra catalyst can help compensate for this and prevent formation of a tacky silicone surface.

Muestras de las resinas BioMed
Cada muestra de las resinas BioMed incluye diseños en relieve o grabados en sus superficies, grosores de 0,5-2 mm e información normativa exclusiva de la resina en cuestión.
Selecting a Mold Type
Aunque el resultado de cada proceso de moldeo puede parecer similar, hay algunos criterios que recomendamos para elegir un tipo de molde. Entre ellos se cuentan la geometría que se quiere alcanzar para la pieza y la capacidad de incorporar socavados y agujeros en el diseño, tu escala de producción y los materiales que quieres fundir. Ofrecemos algunas pautas en la siguiente tabla.
Tipo de molde | Geometría de la pieza | Materiales | Escala de producción |
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Molde de compresión | Sin socavados | Masilla de silicona de dureza alta | Decenas de fundiciones |
Molde llenado por inyección | Socavados leves | Two-part liquid silicones | Decenas de fundiciones |
Sobremolde | Encapsulate internal hardware, minor undercuts | Two-part liquid silicones | Decenas de fundiciones |
Molde de cascarón | Can accommodate large | Two-part liquid silicones | Uso único |
Silicone Molding Step-By-Step
The Formlabs team has developed a step-by-step process for creating a silicone product prototype by combining different aspects of our customers’ successful workflows. One project presented below is a molded silicone keychain with an embedded Apple AirTag device. The other is a gasket designed by OXO. The design guidelines cover all critical steps from importing a reference geometry to adding alignment features for encapsulated hardware. We also used the novel silicone filling method employing an epoxy gun with a 1:1 volume mixing nozzle recommended by Dame Products.
Many of the steps and best practices shared are common across mold types. Each step of the tutorial indicates its relevance to injection filled molds, overmolds, or compression molds.
For information about eggshell molds, the Formlabs audiology white paper 3D Printing Custom Silicone Ear Molds provides a step-by-step guide.
WHAT IS REQUIRED?
From Formlabs:
- Formlabs BioMed Clear Resin or Clear Resin
- Compatible Formlabs SLA printer with up-to-date firmware
- PreForm software (most recent version)
- Compatible Build Platform
- Compatible Resin Tank
- Form Wash, Form Wash L, or Finish Kit
- Form Cure or Form Cure L
Item | Supplier | Notas |
---|---|---|
High-gloss acrylic spray | Krylon | Protective coating |
Ease Release 200 | Mann Release Technologies | Mold Release |
Apple AirTag | Encapsulated hardware | |
Dragon Skin 20 | Smooth-On | Two-part RTV Silicone, Platinum Cure |
Silc Pig | Smooth-On | Colored pigment |
Stirring sticks | ||
Epoxy cartridge | McMaster-Carr | 1:1 ratio |
Epoxy dispensing gun | McMaster-Carr | |
Mixing nozzle | McMaster-Carr | |
C-clamp or spring clamps | ||
Duct tape | ||
Vacuum chamber and pump (optional) | Amazon | |
Pressure pot (optional) | Amazon |
Molding Process: Compression Mold
Item | Supplier | Notas |
---|---|---|
Ease Release 200 | Mann Release Technologies | Mold release |
Castaldo QuickSil | Castaldo | |
Tabletop vice |
WHAT IS REQUIRED?
Overmold
- Import the Reference If you are planning to overmold or encapsulate another object with silicone, import your reference object or substrate in the CAD software of your choice. In this example, we imported a digital replica of an Apple AirTag.
Injection Filled Mold, Overmold, or Compression Mold
- Design the Silicone Part Together, the silicone and any encapsulated items form the base volume. For overmolded parts, aim for a minimum silicone shell thickness of 2 mm. In our compression mold example, the object has a complete through-hole. We recommend defining a core as a separate object. The silicone part plus core can be thought of as your base volume.
- Design the Mold Stock Create a block around your base volume that extends at least 1 cm beyond the outer shell of your part.
- Split the Mold For a basic two-part mold, you will be splitting your base volume into two parts along a defined surface based on a parting line. Start by using draft analysis to define the parting line. Consider how the two halves of your mold will come apart, to ensure that the silicone part can be easily released from the mold. To avoid undercuts, the parting line might be a contour instead of a straight line. Next, extrude the parting line into a surface and use this surface to split your mold. For complex molds that require more than two parts, this process can be repeated multiple times to generate the number of mold parts required.
- Remove Base Volume From the Mold Stock Use boolean subtract in your CAD software to carve out the mold cavity from the solid block. In the case of our compression mold, the individual core component is added back with a boolean addition to one side of the mold, in effect creating two parting lines.
- Check Draft Angles It is a good idea to pause here and consider how your mold bodies will come apart after you inject the silicone. Our customers recommend using at least a 2° draft angle for silicone product prototypes. However, this aspect of silicone mold design is quite forgiving. Because the silicone rubber can generously deform during de-molding, many angles can be handled including 90° angles or slight undercuts. We recommend using the Draft Analysis tool in your CAD program at this step to analyze and edit any areas shown in red beyond the threshold draft angle.
Injection Filled Mold, Overmold
- Design the Gate If you are relying on gravity to fill the recesses of the mold cavity, place the entrance of your gate high on the mold block and then, using a U-shape with a generous bend radius, connect the gate to the mold cavity at the lowest possible point. Filling at this location prevents air bubbles from forming. Boolean subtract the gate from the mold stock. Typically, the central axis of the fill gate is located on the parting line. Another configuration would be a short fill gate that directly connects to a point on your mold cavity; the main air vent will be located on the opposite side.
- Define Air Vents Air is displaced when filling silicone into an enclosed space, so it is natural to place an air vent at the point of the mold that is last to fill. In our example, this is placed at the top of the mold stock. To place additional air vents, it is helpful to think about areas where air is likely to be trapped, and connect vents specifically to points such as sharp turns, corners, or areas where two liquid flow fronts connect. Typically air vents will be cylinders (~0.5-2 mm in diameter) that connect areas of your cavity to the top of the mold. Like the fill gate, it is helpful to align the axis of any air vent on the parting line. Once placed, boolean subtract these features from the mold stock.
Injection Filled Mold, Overmold, or Compression Mold
- Add Mating Features These features align and constrain separate parts of the mold stock to each other. Leave a ~ 0.1 mm offset gap between complementary mating features.
Overmold
- Add Alignment Pins for Encapsulated Devices If you are overmolding or encapsulating a part in silicone, the part must be fully constrained in the mold so it does not shift during silicone casting. Use as few alignment pins as necessary to constrain the part and aim for a pin diameter of ~1.25 mm. Pins should be pointing in the direction of draw, or perpendicular to the parting line of the mold. Note that alignment pins do leave small holes in the surface of the silicone part. If needed, these can be patched after de-molding using a small dab of liquid silicone which is then allowed to cure.
Injection Filled Mold, Overmold
- Add More Mold Features One additional mold feature is a fill trough. A trough is used for overflow of the silicone at both the fill gate and vent locations, and can be designed as a single continuous well that covers all gate and vent features. The trough also contains a reservoir of liquid silicone that can enter the mold during the curing process by freely seeping into the mold cavity to displace bubbles and voids, or to compensate for silicone that enters the interface between mold parts during cure. In this particular example, our trough is 10 mm deep.
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Add a Syringe Inlet We also recommend adding a syringe inlet feature that matches the geometry of your syringe. We made ours slightly oversized, with a 6° angle to fit a variety of syringe and mixing nozzle types.
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Add Pry Points Pry points can be added to assist with disassembly of the mold after curing. These are small rectangular cutouts along the parting line that allow a flathead screwdriver or another tool to be used to separate the mold parts. Our example cutouts extend 5 mm into the mold edge.
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Add Fillets or Chamfers Add fillets or chamfers to angled mold features This is usually the final step after the mold geometry is locked. Adding fillets to soften the edges of the mold can also aid the 3D printing process. When printing a mold stock directly on the build platform, beveling any external corners eases part removal after printing and reduces the amount of resin flash that can accumulate around sharp corners.
Printing the Mold
Injection Filled Mold, Overmold, or Compression Mold
- Select the Resin Many resins work, however Clear Resin or Biomed Clear Resin are great options for visualizing the flow of silicone while casting your part.
- Print the Mold We recommend printing with a 50 microns layer height for a good balance between smooth surface texture and fast printing time. Since silicone picks up fine details on the surface, including layer lines, 25 microns layer height might be needed for some aesthetic applications. Orient your parts on the build plate so that critical interior surfaces are free of support marks. Placing the mold stock flat on the build platform can work in some cases.
- Wash and Post-Cure the Mold It is critical to thoroughly wash excess resin off of the mold stock with clean IPA because uncured resin can inhibit curing of silicone. The mold should also be cured completely to reduce the amount of unreacted monomer on the SLA parts. For Clear Resin, the recommended settings are 15 minutes at 60 °C. For BioMed Clear Resin, the recommended settings are 60 minutes at 60 °C. The preset time and temperature settings on Form Cure work well. The outer surface can be polished to a highly transparent finish. Adding mineral oil to the exterior surfaces is one option to help fill in surface scratches and provide an extremely clear window into the silicone filling process.
Printing the Mold
Injection Filled Mold, Overmold
- Apply Coatings and Mold Release Apply coatings and mold release. Consider using mold release anytime two different materials come into contact with each other. This includes embedded hardware that you plan to insert and remove from an overmolded silicone sheath. Consult our customer workflow table for recommendations. Follow the guidelines on your material packaging, and wait for the coatings to fully cure or dry before moving on to the next step.
- Insert Internal Parts/Hardware Alignment pins help to orient the part that will be encapsulated.
- Close and Clamp the Mold Carefully clamp the mold starting in the direction of the draw, making sure that the mold stock and any encapsulated objects remain in alignment. In our example, we used a 3D printed replica of an Apple AirTag, fabricated in Rigid 10K Resin.
Printing the Mold
Injection Filled Mold, Overmold
If you are incorporating a pigment, mix the pigment into Part B before moving on to the steps below.
A frequent concern when casting silicone is trapping small air bubbles in the mold. This results in voids in the final casted part. A couple of supplemental methods are recommended to manage air bubbles, including degassing liquid silicone in a vacuum chamber prior to mold filling. As a general guideline, check the viscosity of your liquid RTV silicone formula. If it is over 18,000 cps (centipoise) degassing is recommended. If it is below this threshold, a degassing step may not be necessary. Another recommended technique is placing the filled mold in a pressure chamber during silicone curing in order to collapse and shrink any entrained bubbles. A great prototype can be produced without degassing the silicone or curing under pressure, but you can achieve a nearly perfect part using these supplemental methods.
Vat Method
- Degas parts A and B separately under vacuum, if needed.
- Mix parts A and B together vigorously. Typically the two silicone components are mixed in equal volumes. Allow the mixture to degas under vacuum again, or to gently degas in air.
Mixing Nozzle Method
- Degas parts A and B separately under vacuum, if needed.
- Fill each side of an epoxy cartridge system with one part (A or B), using separate syringes to transfer the liquids. Pouring the silicone high above the cartridge in a thin stream will help to avoid remixing air into the silicone.
- Degas parts A and B. Stand upright and allow the silicone to gently degas in air. Because silicone parts A and B remain separate, the filled cartridge can remain for days before you use it.
Molde de compresión
- Mix Parts A and B Thoroughly Mix together equal volumes of parts A and B of the silicone putty and knead by hand. The silicone rubber begins to cure after 90 seconds, so the parts should be kneaded for the minimum time necessary to generate a uniform color.
Molde de compresión
Injection FIlled Mold, Overmold
Vat Method
- Draw the degassed silicone mixture into a syringe. Next, invert the syringe so the nozzle faces up. Allow any air pockets to rise to the top. Depress the plunger to expel the air and extrude a small amount of your silicone to ensure no air bubbles remain in the syringe. Insert into the fill gate and slowly fill the mold until silicone exits from the air vents. If your model has an overflow trough feature, continue filling this area of the mold.
Mixing Nozzle Method
- Assemble the epoxy gun. Insert the cartridges into the gun and screw on the mixing nozzle. It’s helpful to squeeze a little bit of liquid out of the nozzle tip at this stage to make sure the epoxy is properly mixed.
- Fill the mold. Insert the epoxy gun nozzle into the fill gate and slowly fill the mold until silicone exits from the air vents. Again, fill up the trough feature if your mold includes one.
Use a Pressure Pot (optional)
- As an optional step, place the mold in the pressure pot and add your silicone manufacturer’s recommended air pressure to the pot (e.g. ~ 30 psi). This shrinks any bubbles trapped in the mold and forces the material in the trough down into the mold. Let the silicone cure under pressure according to the manufacturer's instructions.
Compression Mold
- Stuff Silicone Into the Mold The silicone should be compacted into both sides of the mold, being sure to catch all details and crevices. Any excess material will simply spill outside the edges of the mold.
- Squeeze Mold Together The mold should be squeezed perpendicular to the parting line. In compression molds, the mating surfaces don’t completely touch until pressure is applied. Close the clamp gently until it does not close further. The recommended Castaldo Quick-Sil silicone rubber cures completely in 20 minutes.
Molde de compresión
Injection Filled Mold, Overmold, Compression Mold
The cure time can range from 10 minutes to several hours depending on the silicone chemistry.
- Define Mold Orientation With a gravity-filled configuration, like our example, the mold can remain oriented upright without an extra sealing step as the silicone cures. With an end-to-end filling configuration, we would experience a backflow of silicone if the filled mold was set on our workbench. After filling, we recommend sealing the gate with duct tape. The compression mold should remain clamped in a tabletop vise while curing.
- De-Mold and Trim the Silicone Part It is normal to develop some flash within and around the parting line. Remove excess silicone from the exterior of the mold first. Pry open the mold by inserting a flat head screwdriver or another flat tool into the pry point and gently twisting to break the seal. Remove the silicone part, being mindful that some silicone may need to be gently trimmed away from any air vents. After removing the silicone part from the mold, use a sharp razor or flush cutters to trim the vent and gate features from the part. Residual bumps can be removed gently with wet fine grit sandpaper. Finally, you can wash the part with soap and water to remove sandpaper and mold release residues.
- Prepare for the Next Casting Molds can be reused multiple times. You may need to clean out vents with a sharp tool and/or reapply mold release before filling with silicone again. It is common to accumulate incompletely cured silicone in the narrow surface between mold blocks. This can be wiped away with a clean cloth.
- Iterate Design It is normal to go through a couple of mold design iterations after trying the full end-to-end workflow. A few design changes you might need to consider include increasing the offset distance between mating features, moving alignment pins to ensure that encapsulated objects are fully constrained, or adding air vents in areas that tend to trap air bubbles during filling.

Dame Products use 3D printed molds for overmolding.
Molde de compresión
Mold material: Production molds are typically made from machined aluminum or steel.
Alignment pins for overmolding: The alignment pins for overmolding are oriented within the plane of the mold’s main parting line, rather than perpendicular to it. These are also designed to retract in and out of the mold, resulting in a silicone layer that does not have dimples and holes created by alignment pins.
Draft angle: Our customers recommend using at least two degrees draft angle for silicone products. While the prototype or short-run production molds presented in this report can handle deep undercuts, these types of silicone geometries must be carefully pried from the mold, and would be difficult to replicate by an automated injection system.
Injection molding configuration: Gravity-fill molds are highly reliable mold configurations for benchtop prototyping. For rapid mass production methods, inlet and outlet geometries are on opposite sides of the mold.
Silicone materials: While silicone chemistry used in production is quite similar to the RTV materials presented in this white paper, both liquid silicone rubbers (LSR) for injection moldingnand heat cured rubbers (HCR) for compression molding typically enter the mold at low temperature, and are then cured at elevated temperature.
Silicone Printing Step-By-Step
WHAT IS REQUIRED?
From Formlabs
- Formlabs Silicone 40A Resin
- Compatible Formlabs SLA printer with up-to-date firmware
- PreForm software (most recent version)
- Compatible Build Platform
- Compatible Resin Tank
- Form Wash, Form Wash L, or Finish Kit
- Form Cure or Form Cure L
From Third-Parties
- IPA (99% or higher): To make wash solvent blend for washing Silicone 40A parts
- N-Butyl Acetate (purchase in the US; purchase in EU): To make wash solvent blend for washing Silicone 40A parts
- Glass Beaker (at least 500 mL in size): To submerge Silicone 40A parts inbwater during the post-cure steps
- Febreze HD (optional): For masking of odor of printed Silicone 40A parts
- 1.5 Gallon Glass Jar (optional): For storing wash solvent and washing printed Silicone 40A parts if not using a Form Wash
- Ultrasonic Cutting Knife (optional): For removing support nubs on Silicone 40A parts
1. Diseño
1.1. Design your parts with the Silicone 40A Design Guidelines in mind.
2. Impresión
2.1. Import File
Check that your version of PreForm is up to date by going to Help, then Check For Updates in the upper left-hand corner. Import or open your part file by dragging them into PreForm, or by going to File and then Open in the upper right hand corner.
2.2. Select Material
Select Silicone 40A by clicking the Printer Type box in the Job Info menu on the right-hand side. Select “Silicone” from the materials grid.
2.3. Orient
PreForm can auto-orient based on Formlabs best practices. To auto-orient, select your part and click Orientation on the left side of the screen. Then, click Auto-Orient Selected.
For best results, you may orient manually using the red, green, and blue actuators surrounding your part. Consider orientating so that areas where a smooth surface texture is most important are facing away from the build platform.
Print directly on the build platform whenever possible. Try to keep the bulk of the part’s weight as close to the build platform as possible and orient long parts parallel to the front edge of the build platform.
2.4. Add Supports
To auto-generate supports based on material properties, select your part and go to Supports on the left side of the screen and select Auto-Generate All.
For optimal results, we recommend manually editing auto-generated supports, or manually placing supports until the part is sufficiently supported (indicated by a green thumbs-up beside Supports in the Job Setup menu). PreForm will indicate in red what areas might require additional support.
If surface texture or post-processing time is a major concern, you may want to consider designing custom supports using CAD software. Guidelines for adding tearaway supports can be found here.
2.5. Layout
Set your part’s location on the build platform by clicking and dragging, using the red green and blue actuators surrounding your part, or by clicking Layout, then Layout All on the right side of the screen. It’s best to place parts in the center of the build platform. When printing multiple parts, space on the build platform can be optimized and material can be saved by overlapping rafts.
2.6. Send to the Printer
Send your job to the printer by clicking the orange Upload Print button on the bottom right. When the Print dialogue box opens, select the printer that you would like to use.
2.7. Set Up the Printer
Shake the Silicone 40A cartridge and then insert it. When using a new cartridge, double check that the silicone bite valve is opening successfully by squeezing it with a gloved finger. Insert a build platform and a compatible resin tank into the printer.
Begin printing by selecting your print job from the printer’s touch screen. Follow any prompts or dialogues shown.
Attention: For full compliance and biocompatibility, Silicone 40A requires a dedicated resin tank and build platform. Only use the Form Wash with other Formlabs biocompatible resins.
3. Posacabado
3.1. Remove the Part
Remove the part from the build platform by wedging the part removal tool or a scraping tool under the part raft and rotating the tool. Parts can also be washed directly on the build platform in the Form Wash.
3.2. Wash
Place the part in the Form Wash filled with an 80/20 mixture of 99% isopropyl alcohol (IPA) and n-butyl acetate. Do not wash with IPA or n-butyl acetate alone. Wash using the recommended setting for Silicone 40A (20 minutes).
If the model is hollow or has internal channels, ensure liquid resin is thoroughly flushed out from these features. This can be done using a syringe filled with the mixture from the Silicone 40A wash. Allow parts to fully dry before post-curing.
3.3. Remove Supports
For rest results, remove supports after washing but before post-curing.
To remove supports, pull gently at the support structure. On thicker parts, just pulling may be sufficient. On thinner parts, consider using flush cutters, or sliding a sharp hobby knife along the part’s surface, being careful not to damage the part itself. An ultrasonic cutter can also be used here for greater precision.
3.4. Post-Cure
Post-cure your part to achieve optimal mechanical properties. Fully submerge the part in a beaker (or other UV-transparent container) of water, and place the beaker of water containing your part into the Form Cure. Use the recommended settings for Silicone 40A (45 min at 60 °C).
Mask the odor of Silicone 40A by adding Febreze HD to the water in the glass beaker before post-curing. For every 500 mL of water, use 12.5 g of Febreze HD. If not treated, this odor will dissipate over time.
3.5. Additional Post-Processing
A miniature, mounted Scotch Brite wheel can be used with a rotary tool to grind down support marks on parts either before or after curing.
Before applying any adhesives, ensure that the part has been thoroughly washed, is dry, and the surface is not tacky or dusty. Formlabs recommends using a primer such as DOWSIL 1200 series or a medical primer. After a primer has been applied, use a silicone adhesive such as DOWSIL 734. Do not use cyanoacrylate glues as they are brittle and leave a crust on the silicone.
Medical Customer Case Studies
Direct Printing with Silicone 40A Resin

FINIS, Inc. está especializada en el desarrollo de equipamiento de natación y deportes acuáticos, incluidos productos punteros como las gafas de natación inteligentes Smart Goggle Max.
FINIS, Inc., a California-based company renowned for its innovative swim-related products, prioritizes quality and performance to meet the evolving needs of swimmers of all skill levels. Led by senior designer David Beittel, the product development team initially used filament 3D printing for rapid prototyping but sought more detailed and isotropic parts. That’s when they transitioned to Formlabs Form 3+ Stereolithography (SLA) 3D printers and Silicone 40A Resin. This resin proved invaluable for swift adjustments, overnight functional prototype printing, and achieving characteristics close to final production materials.
Historically, FINIS relied on labor-intensive silicone casting in traditional molds, leading to long production lead times. With the introduction of the Form 3+ 3D printers and Silicone 40A Resin, the team overcame challenges associated with mass-producing silicone parts. They were able to produce production-quality parts in a mere eight hours for just $10 a piece. This is a significant undercut to outsourced urethane casting, which has the usual expenditure of over $1,000 and a three-week timeline. The 3D printed silicone gaskets successfully underwent rigorous water tightness assessments within a swimming pool environment and demonstrated elasticity closely mirroring final production characteristics. Silicone 40A has become an essential tool for refining designs and ensuring optimal performance throughout FINIS, Inc.’s development process.
Injection Filled Molds for Product Prototyping With Glassboard

BioMed Clear Resin is used to create transparent molds which can be inspected for air bubbles or other imperfections.

Glassboard is a product design consulting firm in Indianapolis, IN. Their design team uses silicone in molds for a very wide variety of prototyping applications from silicone menstrual cups, to custom fittings and overmolds, to seals, gaskets, and o-rings. Glassboard typically uses molds that are made of multiple parts that can be disassembled to remove the casted silicone and then reused for multiple castings.
A typical mold design at Glassboard, such as the one used for the Sunny Menstrual Cup, is an injection filled mold aided by a gravity-fill configuration. Liquid silicone is injected through a port at the top of the mold, runs down a channel to enter the bottom of the mold cavity, gradually fills to the top of the cavity, and exits via narrow air vents at the top of the mold.
An innovative feature of Glassboard mold design is a trough reservoir at the top of the mold. Troughs are used to contain the overflow of the silicone at both the gate and vent locations. Another purpose of the trough is to allow excess silicone to enter into the mold after filling to displace voids created by collapsing air bubbles or by silicone seeping into the narrow surface between mold blocks.
Silicone Overmolding of Customer Beta Prototypes With Dame Products

Dame Products employs an overmolding method to produce customer beta prototypes with embedded hardware. Their mold is printed in Clear Resin.
Dame Products is a Brooklyn-based startup that designs products for the health and wellness industry. Their product line incorporates complex ergonomically shaped hardware that is fully encapsulated in a layer of skin-safe silicone in vibrant colors. The team employs silicone overmolding with 3D printed molds to produce customer beta prototypes.
Each 3D printed mold stock is a two or three part injection filled mold that has anchoring features for small internal hardware. Parts A and B of a platinum-catalyzed liquid silicone are loaded into two sides of a 50:50 ratio epoxy cartridge, and attached to an epoxy gun with a mixing nozzle. This innovative method simultaneously mixes the silicone components while gradually forcing the liquid silicone into the mold.
Dame engineers can prototype dozens of overmolded devices in one day by rotating through three or four SLA printed molds. While the silicone rubber from one prototype is curing, the next can be de-molded and prepared for the next fill. Trimming and cleaning of prototypes happens in parallel. When prototype hardware is returned to the company, the beta device is bleached, the thin silicone layer removed, and the internal hardware is reused in a new prototype.
End-Use Overmolded Grippers With PSYONIC

PSYONIC encapsulates the Ability Hand fingers using a silicone overmold configuration. Some molds include a Tough 2000 Resin mold insert to anchor the encapsulated “bone” feature in the mold.
California-based PSYONIC is reinventing limb prosthetics with the world’s first touch-sensing bionic hand. The team uses 3D printing as a critical step in manufacturing almost every component of their device. This includes mechanical fingers that are encapsulated with silicone using an SLA 3D printed mold.
The molds are produced by taking the inverse of the finger or thumb shape, subtracting it from the mold stock, and adding inlets and air vents for injection of two-part platinum cure silicone. The mold also accommodates the structural “bone” component of the finger, which is fabricated using an FDM 3D printer.
Designers at PSYONIC are able to use each mold dozens of times before it wears out, and when this happens they can simply print a new mold and start injecting silicone again the next day. The team also directly contrasts Formlabs Clear Resin to their previously used fused deposition modeling (FDM) thermoplastic molds, namely referring to the upgrade in surface quality. Silicone picks up any texture or defect in the mold cavity, including 3D printing layer lines, so the smooth surface quality of Formlabs resins has been beneficial.
Silicone Injection Molding of Custom Makeup Effects With Dreamsmith

Designing and printing a complex shape and highly-detailed silicone mask with 3D printing.
Dreamsmith is an entertainment props and makeup effects firm based in South Africa. Their team has worked on designs for popular shows like Raised By Wolves, in which one particular effect needed was a silicone face mask incorporating a highly geometric exterior and an interior that conformed to the face of their actor.
Using the Form 3L, their team printed a mold that utilized optical scan data from the actor’s face for one interior surface, and a sharp geometric tile pattern for the other. While their design looks quite different from some of the product design examples in this report, the Dreamsmith team had many of the same material concerns, including ensuring compatibility of their mold material with skin-safe platinum cure silicone. They ultimately selected Formlabs Rigid 10K Resin for its high precision.
Eggshell Mold for Custom Medical Devices With Cosm

Cosm employs eggshell molds to produce custom silicone medical devices. Their thin-walled mold is printed with Biomed Amber Resin.
Cosm is a medical device company revolutionizing treatment for uterine prolapse, a common but often overlooked medical condition, with patient-specific silicone pessaries. The pessary is a non-surgical treatment approach in which a small support device is inserted below the uterus by a doctor. However standardized designs require fit by trial and error, and patients often give up on treatment before finding the proper fit.
The Cosm team’s approach utilizes data from a novel ultrasound technique to design a custom device tailored to a patient’s own anatomy. The Cosm team turned to Formlabs SLA printers for their silicone tooling, developing an eggshell-style conformal mold that is filled with medical-grade silicone and then cracked away to reveal the patient-specific silicone implant. The moldsare made from Biomed Amber Resin printed on the Form 3B.
Empieza a crear productos sanitarios de silicona
La silicona se usa en ámbitos tan diversos como el prototipado rápido, las pruebas de fase beta y las etapas de validación en el desarrollo de productos, además de para llevar a cabo de forma rentable una fabricación personalizada o de bajo volumen de piezas de uso final. El ecosistema de Formlabs hace posible imprimir en 3D con la Silicone 40A Resin e imprimir moldes de silicona para fabricar productos sanitarios, prótesis adaptadas a los pacientes y componentes de audiología, así como piezas con geometrías complejas difíciles de obtener mediante métodos tradicionales.
Para ver las guías completas tanto de la impresión 3D de moldes de silicona como de la impresión con silicona, descarga el libro blanco.