Mechanical Product Engineer

About Lumilens

At Lumilens we are building the critical photonics infrastructure that powers tomorrow’s AI supercomputing. From chip-to-chip optical interconnects to scalable photonic engines, Lumilens is unlocking a new era of computing - faster, cooler, and massively more efficient.

We’re a well-funded startup backed by Mayfield and led by veterans who’ve built and scaled some of the most transformative technologies in the industry. At Lumilens, we’re developing high-speed photonics products purpose-built to power the future of AI infrastructure and high-performance computing.

This isn’t incremental innovation, it’s a ground-floor opportunity to rethink the optical layer from the silicon up. You’ll work alongside a team of world-class engineers solving some of the hardest challenges in scaling optical systems. If you're looking for mission, momentum, and the chance to make an outsized impact, jump on the rocket ship. We’re just getting started.

Position Overview

We are seeking a hands-on Mechanical Product Engineer to serve as the primary mechanical engineering interface between Lumilens’ hardware design teams and our worldwide contract manufacturers (CM) and supplier network.

In this role you are the mechanical DRI (Directly Responsible Individual) for the manufacturing launch, sustaining, and continuous improvement of Lumilens’ next-generation optical and AI infrastructure. You will own the full arc from early development engagements, through NPI build planning, through volume production release - driving quality, cost, yield, and schedule with the CMs and key suppliers while partnering upstream with Optical, Hardware, and Mechanical Design Engineering teams.

This role focuses on precision mechanical design, product packaging, structural design, thermal/mechanical considerations, and system integration - turning loosely defined requirements into robust, manufacturable hardware.

This position is ideal for an engineer who combines deep mechanical product knowledge with a passion for manufacturing process excellence, supplier development, and cross-functional execution at a global scale. And for someone who enjoys building, debugging, and iterating quickly while contributing to mechanical architecture, detail design, tolerance control, and design-for-manufacturing decisions that impact performance, automation, reliability, cost, and scalability.

Key Responsibilities

• Proto / Engineering Validation Test - Build readiness, BOM validation, mechanical fit checks, first-article inspection at CM.

• Design Validation Test - DFM/DFA reviews, tolerance audit, tooling buyoff, GD&T deviations, PFMEA launch.

• Process Validation Test - Process capability studies (Cpk), yield ramp, packaging qualification, and cosmetic defect standards.

• Mass Production / Sustaining - ECO execution, supplier change management, cost reduction, long-term supply continuity.

• Failure Analysis - Drive root‑cause analysis for prototype, production, and field‑reported mechanical issues, delivering containment actions and long‑term corrective solutions

• Collaboration - Work closely with product owners, optics, test, electronics, and manufacturing teams to resolve technical tradeoffs, maintain execution timelines, and ramp to high volume production.

• Nice to have - Design manufacturing tools, jigs, and fixtures. Work directly with fabrication vendors and suppliers to communicate requirements, validate prototypes, and prove-in tools, jigs, and fixtures for production.

What You Will Do

• Own end-to-end mechanical NPI execution at CMs and Key Suppliers/Partners from proto builds through mass production release and yield stabilization.

• Collaborate in material selections, interfaces, and finishes suitable for precision, optical, ESD‑sensitive, and clean manufacturing environments

• Lead mechanical DFM/DFA reviews on housing, sheet metal, die-cast, injection-molded, and extruded components - translating design intent into manufacturable specifications.

• Ensure clear engineering specifications, drawings, and documentation that communicate design intent across internal teams and suppliers

• Develop and own Process FMEAs (PFMEA) and Control Plans for mechanical assembly lines; define inspection criteria, torque specs, and cosmetic acceptance standards (IPC-A-610, Lumilens internal).

• Drive tolerance stack-up analysis reviews with CMs and Key Suppliers/Partners to ensure fit, form, and function across multi-vendor supply chains; disposition non-conformances via the MRB process.

• Author and manage Engineering Change Orders (ECOs) through Lumilens' PLM system (Arena), coordinating with supply chain, CM, and design engineering for zero-impact transitions.

• Conduct CM and Key Supplier/Partner site audits and process capability assessments; track and improve Cpk values for critical mechanical dimensions and sub-assembly operations.

• Partner with commodity management and strategic sourcing to qualify alternate mechanical suppliers; conduct supplier technical reviews and first-article qualifications (FAI/PPAP).

• Manage mechanical tooling asset lifecycle - injection mold, stamping die, and die-cast tool maintenance, repair, revision, and capacity planning across CM sites.

• Collaborate with Lumilens’ Reliability Engineering team to support HALT/HASS, vibration, shock, and thermal cycling qualifications per NEBS GR-63 and Lumilens internal standards.

• Drive mechanical cost reduction projects including part consolidation, DFM-driven redesigns, tooling amortization strategies, and regional sourcing optimization.

• Develop and maintain Lumilens’ mechanical manufacturing standards, best-practice documents, and CM-facing work instructions.

• Mentor junior mechanical product and manufacturing engineers and provide technical guidance on process escalations during high-volume ramp events.

Nice‑to‑Have Alignment

• Experience owning system calculations or platform‑level mechanical architectures

• Background designing automation equipment, test fixtures, or thermo‑mechanical systems

• Strong root‑cause problem‑solving mindset (5 Whys, Fishbone, structured RCA)

• Experience building internal tools, configuration logic, or design frameworks to scale engineering output

Required qualifications

• B.S. or M.S. in Mechanical Engineering or Manufacturing Engineering

• 8+ years in product/manufacturing engineering for networking, servers, telecom, or consumer electronics hardware

• Deep DFM/DFA expertise: sheet metal, die cast, plastic injection molding, extrusions

• GD&T proficiency per ASME Y14.5; tolerance stack-up methods (RSS, worst-case)

• Hands-on CM/ODM management at Tier 1 EMS providers in Asia

• Process capability analysis: Cpk, SPC, control charting

• PLM/ECO management (Agile, Arena, Windchill, or equivalent)

• PFMEA and Control Plan development experience

• IPC-A-610 or equivalent mechanical/cosmetic inspection standards

• Strong written/verbal communication for multi-site, cross-functional teams

Preferred qualifications

• M.S. in Mechanical or Manufacturing Engineering

• NEBS GR-63 / GR-1089 qualification test execution

• APQP / PPAP process knowledge (automotive-to-electronics transfer)

• Six Sigma Green Belt or Black Belt; Lean / Kaizen facilitation experience

• Familiarity with liquid cooling and advanced thermal assembly manufacturing

• NX, CREO, or SolidWorks 3D CAD proficiency

• Mandarin Chinese language skills (CM site engagement)

• PMP certification

Core Technologies, Processes & Tools

DFM / DFA / PFMEA / Control PlansGD&T / ASME Y14.5 / Tolerance Stack-Up / Cpk / SPC / ECO Management Agile / Arena PLM / FAI / PPAPIPC-A-610 / NEBS GR-63MRB / NCR Disposition / Tooling Lifecycle Mgmt / NX / CREO / SolidWorks / Sheet Metal / Die Cast / Injection Molding / Die Bond Tooling / Material Handling Tooling / Test Fixtures / Lean / Six Sigma / CM Site Audits / Supplier Qualification / HALT / HASS / Cost Reduction (VE/VA)

Global travel

This role requires periodic travel to CM and Supplier manufacturing sites in Taiwan, mainland China, Malaysia, and Thailand - primarily during NPI build events, supplier qualification activities, and yield ramp escalations.

What We Offer

• Competitive salary and meaningful equity in a high-growth company

• Comprehensive health, dental, and vision coverage

• Flexible time off policy

• Opportunity to work on cutting-edge technology shaping AI infrastructure

• Collaborative, high-caliber engineering environment