Engineering Intern – Materials & Resin Development

Location: Huntington Beach, CA
Duration: 3-6 month Internship
Compensation: $28-$32/hr

About the Role

SprintRay’s Biomaterial Innovation Lab is seeking an Engineering Intern to support the development of next-generation dental 3D printing resins for DLP and LCD printing platforms. In this hands-on, on-site lab role, you will contribute to resin formulation, print process evaluation, post-processing studies, and material characterization. You’ll work closely with a cross-functional team to generate data, troubleshoot performance issues, and accelerate iteration on new resin systems.

Key Responsibilities

• Assist in photopolymer resin formulation (mixing, batching, additive screening, pigmentation, and process controls).

• Support experimental planning and design-of-experiments (DOE) to evaluate formulation and process variables.

• Run DLP and LCD 3D printing trials to assess printability, cure response, feature fidelity, accuracy, and surface quality.

• Evaluate process windows (exposure settings, layer thickness, build orientation, supports) and document outcomes.

• Support post-processing optimization (cleaning/washing, UV curing, thermal treatments as applicable) and quantify impacts on properties.

• Perform materials testing and characterization on resins and printed samples, such as:

  • Viscosity / rheology measurements

  • Cure behavior / degree of cure (as applicable)

  • Mechanical testing (tensile/flexural/compression, hardness)

  • Dimensional accuracy, shrinkage, and stability

  • Visual/optical properties (color, translucency) as applicable

• Analyze and summarize data; maintain clear lab documentation (notebooks, protocols, reports, and traceable datasets).

• Collaborate with engineers/scientists to troubleshoot issues and propose improvements.

Follow all lab safety procedures and quality practices applicable to medical device development.

Required Qualifications

• Minimum Bachelor’s degree (completed or in progress) in Biomedical, Chemical, Mechanical Engineering, Materials Science, Chemistry, or a closely related field.

• Ability to work on-site in Huntington Beach, CA for the full internship term (3–6 months).

• Hands-on lab experience (academic or industry) in materials, polymers, chemistry, formulation, or testing.

• Comfort working with data and documentation (Excel/Google Sheets; basic plotting/analysis).

• Strong communication skills and ability to work effectively in a team environment.

Preferred Qualifications

• Experience with photopolymers, resin chemistry, polymers, or composites.

• Familiarity with DLP and/or LCD printing workflows and parameter optimization (exposure, layer thickness, supports).

• Experience with characterization tools (e.g., viscometer/rheometer, FTIR, DSC/DMA, mechanical test frames).

• Interest in digital dentistry, dental materials, or medical device R&D.

• Exposure to regulated development environments (ISO 13485, GMP) is a plus.

What You’ll Gain

• Hands-on experience developing and validating dental 3D printing resin materials for DLP/LCD platforms.

• Mentorship from a multidisciplinary team across materials, process, and device development.

• Opportunity to contribute to new products and workflows in a fast-moving digital dentistry environment.

Employment Type

Internship (3-6 months)

About SprintRay

SprintRay is rewriting the rules of dentistry with technology that’s smart, fast, and designed to make life easier for dental professionals. Since 2014, we’ve been on a mission to deliver the most advanced 3D printing solutions in the industry—combining hardware, software, and materials into one seamless ecosystem.

But what really makes SprintRay different is our people. We’re a bold, global team of innovators, problem-solvers, and doers who thrive on pushing boundaries and challenging the status quo. Every product we create is driven by a simple goal: help dentists spend less time on repetitive tasks and more time changing patients’ lives.

Our culture is entrepreneurial, collaborative, and fueled by curiosity. We celebrate diverse perspectives and believe the best ideas can come from anywhere. Whether we’re building next-generation AI tools, designing new materials, or supporting our customers on the front lines, we’re united by the same passion—transforming digital dentistry and having fun while we do it.

At SprintRay, the future of dentistry is being printed today. Want to be part of it?