Principal Mechanical Engineer

Company Description Boston Engineering is seeking a Principal Mechanical Engineer to join our team in Waltham, MA!

Boston Engineering is where innovative ideas become real-world technologies. Headquartered in Waltham, Massachusetts, we've spent more than 30 years partnering with commercial and government clients to solve complex engineering challenges and bring breakthrough products to market. From advanced robotics and autonomous systems to medical devices, digital solutions, defense technologies, and industrial automation, our teams work on meaningful projects that push the boundaries of what's possible.

Why Join Boston Engineering?

Build products with real-world purpose. Contribute to technologies that address challenging commercial and government needs.

Own consequential technical decisions. Shape mechanical concepts and system architecture, guide design tradeoffs, and help clients choose a path forward.

Stay close to the work. Combine technical leadership with design, prototyping, analysis, and testing.

Keep expanding your expertise. Work across industries alongside mechanical, electrical, software, systems, and manufacturing engineers.

Multiply your impact. Mentor engineers, develop future technical leaders, and strengthen engineering practices across the organization.

See how Boston Engineering helps clients turn complex ideas into real-world products and technologies Watch:
Boston Engineering – Product Development Services

Job Description We are looking for a Principal Mechanical Engineer who combines hands-on design expertise with the ability to set technical direction, lead multidisciplinary teams, and build trusted client relationships.

You will guide complex product development efforts from early concepts through manufacturing, with particular emphasis on motion systems, robotics, precision electromechanical systems, and products for demanding environments. You will help teams navigate ambiguity, make critical design decisions, and balance performance, cost, reliability, and schedule.

This role offers the opportunity to remain deeply involved in engineering while expanding your influence through technical leadership, mentoring, and client engagement.

What You Will Do Lead technical direction and product development

Serve as the mechanical technical lead for complex, multidisciplinary product development projects, owning major technical areas and their results.

Translate client needs into product requirements, engineering specifications, mechanical architectures, and development plans.

Guide system-level architecture and interfaces in partnership with electrical, software, systems, and manufacturing engineers.

Resolve novel engineering challenges, anticipate technical risks, and lead teams through ambiguous requirements and changing priorities.

Make and communicate critical design tradeoffs that balance performance, manufacturability, cost, reliability, and schedule.

Design, build, and validate

Develop innovative mechanical designs from concept through production using Creo and/or Solid Works.

Design, build, and test proof-of-concept models, breadboards, prototypes, and production-ready systems.

Apply expertise in motion systems, robotics, and precision electromechanical design, including integration with motion controls.

Lead engineering analyses, design reviews, and verification activities to establish that designs meet requirements.

Apply Design for Manufacturing (DFM), Design for Assembly (DFA), design for cost, and reliability principles throughout development.

Lead teams and strengthen engineering capability

Lead cross-functional engineering teams through major technical portions of projects, aligning disciplines and resolving technical disagreements.

Partner with project managers to define scope, estimate effort, plan technical work, and manage risks and dependencies.

Mentor engineers through design reviews, problem-solving, and direct coaching; help develop future technical leaders.

Establish and improve engineering methods, design standards, and best practices across projects.

Ensure engineering work and documentation meet Boston Engineering’s Quality Management System requirements.

Partner with clients and support business growth

Serve as a primary technical interface for clients, communicating recommendations, risks, and tradeoffs clearly to technical and executive audiences.

Build client confidence through sound engineering judgment, clear communication, and accountability for technical outcomes.

Lead technical…