William Gaffney

Lead Mechanical Design Engineer | Medical Device R&D | Injection Moulding Expert | Steering Complex Product Development from Concept to Class III Launch

Ireland

About

Mechanical Design Engineer with 10+ years of experience specialized in navigating the complexities of high-reliability medical device development, from initial concept through to design verification. My career is driven by an intense curiosity for solving ambiguous technical challenges and a passion for delivering robust, life-changing engineering solutions. Technical Leadership & Impact: Curiosity-Driven Problem Solving: I apply advanced analytical methods, including non-linear FEA and CFD, to decode failure modes and optimize injection-moulded systems. Strategic Design Oversight: Experienced in managing technical design outputs, ensuring rigorous adherence to ISO 13485 standards while leading cross-functional teams and mentoring junior engineers. Manufacturability & Risk Control: Passionate about bridging the gap between design and production through expert DFM/DFA, tolerance analysis, and comprehensive dFMEA/pFMEA management. I thrive in regulated environments where precision is paramount, leveraging a detail-oriented approach to translate functional requirements into scalable, manufacturable mechanical architectures.

Experience

  • Jabil (Bray, County Wicklow, Ireland)
    • Senior Project Engineer
      Feb 2026 - Present · 6 mos

    • Lead Mechanical Design Engineer
      Jan 2025 - Present · 1 yr 7 mos

      Directed the design recovery of a 12-component DPI assembly, identifying critical tolerance stack-up issues that reduced scrap rates by 30% and secured a €12M production line. Managed a cross-functional team of 5 engineers, implementing a new GD&T governance framework that reduced design iteration cycles by 40%

    • Senior Design Engineer
      Jul 2023 - Jan 2025 · 1 yr 7 mos

      Technical Design Authority: Served as the Technical Lead for Dry Powder Inhaler (DPI) device design and verification, ensuring all mechanical architectures met stringent functional requirements. Risk Management & Compliance: Managed dFMEA and pFMEA throughout the design outputs phase to mitigate production risks and ensure full alignment with regulatory standards. Advanced Characterization: Led the design characterization, axial/torque testing, and analysis of complex injection-moulded components to validate mechanical integrity. Strategic Verification Planning: Developed and executed comprehensive Design Verification (DV) and Clinical Design Verification testing plans for both DPI and surgical instrumentation. Rapid Iteration & Prototyping: Directed rapid prototyping cycles for products and high-precision fixtures, accelerating the evaluation and iteration of design concepts. Documentation Governance: Held responsibility for the drafting, technical review, and approval of critical design documentation, maintaining high standards of design traceability.

  • Test & Development Engineer at Nammo Ireland Limited
    May 2022 - Jun 2023 · 1 yr 2 mos

    Acceptance testing of qualified hardware for flight including functional, vibrational, flow and cleanliness. Increased piece part cleaning capacity 8 fold and improved in piece part serialisation. Decreased cycle time and reduced setup difficulty of complex build operations. Diagnosis, rebuild and elimination of FOD in a high purity flow testing machine. Introduced lean principles to work stations and workflows. Created and introduced new processes to AS9100 Introduced new technologies to characterise precise parts for assembly.

  • Mechanical Engineer at Carten Controls Ltd.
    Nov 2018 - May 2022 · 3 yrs 7 mos

    • Lead Engineer in design & validation of products to business requirements • Assembly and reverse assembly of products for analysis and report writing. • Testing, data recording and reporting of product performance. • Calculation & specification of mechanical, pneumatic, and electrical components of product for special application environments along with supporting documentation • Collaborative CAD design of new product for individual customer requirements, eliminating non-critical design elements and focusing on applicable testing. • Manufacturing support, problem solving and RCAs. • Validation testing of critical components for production use, routine disassembly and inspection of product for damage and potential failure modes. • Flow testing of products to capture flow characteristics. • Material qualification against hydrogen embrittlement to ISO and TPED standards • 3D printing: Plastic selective laser sintering (SLS), fused deposition modelling (FDM) and wire arc additive manufacturing (WAAM)

  • Farm assistant at Bosch Dairy Farm
    Jul 2018 - Oct 2018 · 4 mos

    Calf Rearing, Cow herding and machine driving.

  • Mechanical Product Engineer at Merlyn Showering
    Feb 2016 - May 2018 · 2 yrs 4 mos

    Solidworks company implementation & training • Aluminum profile design optimisation using FEA and mechanics • Prototyping, testing and evaluation of existing product upgrades • New product training for field engineers • Investigation of test and product failures and establishing root cause of failure • Product installation and repair brainstorming with field engineers • New product manufacturing zone build, production run testing, validation and in Birmingham • New product patent feasibility study • Product development of new product ranges to market o Project planning and management o Concept development with suppliers o Prototype design, machine, 3D printing, install, function, durability and functional testing o Ergonomic Study: Product testing using force gauge & accelerometers