Senior Mechanical Design Engineer – Plastics & Injection Molding Specialist
About the Role
An innovative and rapidly growing organization in the pharmaceutical and medical device space is seeking a Senior Mechanical Design Engineer with deep expertise in plastics and injection molding. This role will lead the design, development, verification, and validation of complex mechanical and electromechanical devices, with a strong focus on high-volume injection-molded components and assemblies.
This is a highly visible, hands-on technical leadership position ideal for someone passionate about designing precision plastic components for regulated, high-performance applications.
Key Responsibilities
- Lead end-to-end mechanical design of plastic components and assemblies, including housings, fluid paths, needle shields, dose mechanisms, and multi-component systems
- Serve as the subject matter expert in injection molding, including material selection, tooling strategy, and process optimization
- Apply advanced knowledge in insert molding, over-molding, and multi-shot molding techniques
- Perform and interpret Moldflow (or equivalent) simulations including fill, pack, cooling, warpage, and defect prediction
- Drive Design for Manufacturability (DFM) and Design for Assembly (DFA) from concept through production
- Conduct tolerance stack-ups and structural analysis for plastic components
- Partner with manufacturing teams to develop and validate processes, including IQ/OQ/PQ activities
- Lead risk management efforts (ISO 14971), focusing on plastic materials, molding defects, and assembly risks
- Ensure compliance with applicable regulatory standards (ISO 13485, FDA 21 CFR Part 820, ISO 10993, ISO 11608)
- Provide mentorship and technical guidance to junior engineers and cross-functional teams
- Support continuous improvement initiatives for cost, quality, and efficiency
Qualifications
Required
- Bachelor’s degree in Mechanical Engineering, Plastics Engineering, or a related field (Master’s preferred)
- 10+ years of progressive experience in mechanical or product design
- Minimum 7+ years focused on plastic component design and injection molding, ideally in medical device or regulated environments
- Strong hands-on experience with Moldflow or similar simulation tools
- Demonstrated expertise in DFM/DFA for high-volume injection-molded components
- Experience with:
- Injection molding process development and troubleshooting
- Biocompatible and engineering-grade material selection
- Complex plastic assemblies with tight tolerances
- Knowledge of cGMP, FDA, and ISO standards (ISO 13485, ISO 14971, 21 CFR Part 820)
- Proven success leading validation activities (IQ/OQ/PQ)
- Proficiency with CAD tools (SolidWorks strongly preferred)
- Experience mentoring engineers or providing technical leadership
Preferred
- Lean Manufacturing or Six Sigma certification (Green/Black Belt)
- Experience with DOE, scientific molding, and hot runner systems
- Prior work on drug delivery devices such as autoinjectors, pen injectors, or combination products
Work Environment
- 100% onsite role based in Portsmouth, NH
- Frequent collaboration with manufacturing, quality, and R&D teams
- Hands-on involvement in both engineering design and production support
Compensation & Benefits
- Base salary: $150,000 annually, plus potential performance bonus
- Comprehensive medical, dental, and vision coverage – 100% employer-paid for employees and dependents
- 401(k) with company match
- Discretionary time off (DTO) + paid holidays
- Professional development support (training, conferences)
- Potential for equity/stock-based incentives