Formlabs Clear Cast resin is an engineering-grade resin developed by Formlabs for lost wax casting applications.

It enables highly accurate 3D printed patterns to be used directly in the casting process, with a margin of error of just 0.25 mm compared to the design. When used with Formlabs SLA 3D printers, this resin delivers precise results, making it an excellent option for industries requiring intricate and detailed castings for the production of metal parts for a wide range of applications.

Video 1: Industrial investment casting with the Clear Cast resin. Source: FormLabs

One of the key benefits of Clear Cast Resin is its extremely low thermal expansion (94.8 μm/m/°C), which minimizes cracking in the ceramic shell and ensures reliable castings. Additionally, the resin is entirely antimony-free, offering a clean burnout process with low ash content (<0.20%) and no heavy metal contamination, resulting in pristine final castings.

Image 1: Patterns 3D printed with the Clear Cast resin and final cast parts. Source: FormLabs

The Clear Cast Resin is compatible with a wide range of metals and shell systems, allowing foundries to produce new designs in record time, reduce costs, and accelerate production cycles. It replaces traditional wax patterns typically used in lost wax casting, offering greater design flexibility with more complex geometries and faster iteration processes, eliminating the need for dedicated tooling.

The workflow

It is recommended to use Clear Cast Resin in conjunction with lattice generation software for large-scale parts, especially those with wall thicknesses greater than 3 mm. The process of working with the Clear Cast resin is straightforward and typically involves the following steps:

Image 2:The workflow with the Clear Cast resin. Source: FormLabs

1. Create a shell, lattice it and add drainage holes to the part with a tool such as Materialise Magics or Formware. Then orient the pattern, support it and split it into layers in PreForm.
2. 3D print the pattern with a Formlabs SLA 3D printer. Wash the workpiece, cure it and remove the supports. Plug the drainage holes with wax or cure a small amount of Clear Cast resin over the holes.
3. Attach the pattern to a casting tree.
4. Continue with the rest of the casting process: shell making (4), pattern burnout (5), metal pouring (6), shell removal (7) and finishing (8).

For more information on the nature of traditional investment casting, 3D printing aided casting, and the complete workflow with the Clear Cast resin, please consult the White Paper in the Attachments section or the Formlabs webinar on the benefits of working with the Clear Cast resin.

Printer compatibility

The Clear Cast resin is compatible with various printers and accessories from the Formlabs Form 3 and Form 4 ecosystem. It works seamlessly with the Form 2, Form 3, Form 3+, Form 3B, Form 3B+, Form 3L, Form 3BL, Form 4, Form 4B, Form 4L, and Form 4BL printers. The resin is also supported by the Form 2 (PDMS), Form 2 LT, Form 3 V2.1, Form 3L V3, Form 4 and Form 4L resin tanks, as well as the Form 3, Form 3 2, Form 3 Stainless Steel, Form 3L, Form 3L 2L, Form 4, Form 4 Flex and Form 4L L build platforms.