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3D Printing Investment Casting Patterns

3D printing offers an effective tool-less solution for investment casting patterns with Stereolithography (SL). As an alternative to wax and wood, SL builds patterns with a UV laser that cures and solidifies thin layers of resin. Stratasys Direct builds SL investment casting patterns in a nearly hollow structure with a sparse internal lattice structure and thin walls. This proprietary build style translates to proportionately less ash and minimized thermal expansion forces during flash firing.

Stratasys Direct utilizes two Stereolithography materials for investment casting patterns. SC 1000P is a custom photopolymer formulation developed for low cost investment casting patterns. SC 1000P has low water absorption, and patterns built with this material are less prone to dimensional distortion. SOMOS® Element is a newer antimony-free formulation for investment casting patterns. This material is specifically used when a project calls for casting with reactive metal alloys where antimony may contaminate the cast metallurgical properties.

Stereolithography offers a new design freedom, unbound to tooling. Designs can be easily altered and gating systems can be proven out prior to tooling. SL delivers excellent pattern accuracy and repeatability, at less expense than conventional methods. These benefits translate to higher yields in the casting process and makes the piece easier to ship and more durable in-transit than a wax pattern.

Expertise in Action

Each foundry is unique, which is why we tailor the process and product for each customer’s distinctive operations. We work to fit into each customer’s unique operations by utilizing a successful process. We start by associating each project with lot sizes, materials, as-cast shrink compensation, surface roughness and dimensional requirements to ensure on-time delivery of quality patterns.

Then, printing parameters are customized to each pattern’s geometry and cast metal alloy. The patterns are optimized with low CTE, print time and material usage. Stratasys Direct has significant experience seamlessly bonding and assembling large SL patterns. Projects more than seven feet in diameter have been assembled with custom assembly fixtures and expertly delivered in large part packaging. We apply specific surface finishes to parts in order to work with foundry-specific face coats. Our sophisticated leak testing device checks each pattern for a perfect seal, and we offer vacuum ports and testing equipment for quality control at the foundry.

Custom Tools for Foundry Functions

Stratasys Direct offers a host of advanced manufacturing solutions for developing manufacturing tools and aids for foundry customers including hybrid wax setters, wax pattern assembly jigs, straightening fixtures, pattern and core inspection gauges, sand casting patterns, match-plates and core-boxes.

Our engineers are experts in examining a customer’s unique operations and identifying areas that custom jigs, fixtures and other manufacturing aids could transform your production floor.

Even with a centuries old manufacturing process, 3D printing can widen foundries customer base by offering a compatible processes and custom tools.