Senior Mechanical Design Engineer

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