Electric Nail Buffer

Designing a premium electromechanical consumer product from concept through mass production.

Role

Lead Mechanical Engineer

Technologies

Injection Molding

Electronics

Ultrasonic Welding

Manufacturing

Asia

Competitive Benchmarking Takeaways

Noise

Quiet enough for sleeping babies

Visibility

Integrated task lighting for nap or night time use

Ergonomics

Natural grip and intuitive controls

Storage

One-handed access while holding a baby and must retain all parts for on the go use

Performance

Optimized RPM, grit selection, and head replacement

Competitive Device Evaluation

Competitive Noise Testing

Competitive Storage Solution Evaluation

Competitive RPM Testing

Translating Insights Into Design

Noise

Insight: Parents frequently trim nails while babies are asleep.

Engineering Solution: Benchmarked competitive RPM and motor decibel levels to establish a performance target, then optimized motor selection and drivetrain to minimize operating noise while maintaining effective filing performance.

Visibility

Insight: Nail trimming often happens in low-light environments.

Engineering Solution: Integrated an LED task light positioned to illuminate the nail without creating glare or obstructing the user's view.

Ergonomics

Insight: Existing products required awkward hand positions and unintuitive controls.

Engineering Solution: Refined the grip geometry, thumb reach, and button placement through iterative prototypes to improve comfort and one-handed operation.

Storage

Insight: Parents often need to access the buffer with one hand while holding a baby, and the kit is frequently carried in a diaper bag. Competitive cases were difficult to open one-handed and allowed the buffer heads to come loose, leaving the contents disorganized in transit.

Engineering Solution: Developed a compact storage case with intuitive one-handed access and dedicated retention features for the device and each interchangeable head, keeping every component organized, protected, and securely in place during travel.

Performance

Insight: Competitive products either removed material too slowly or felt overly aggressive.

Engineering Solution: Evaluated rotational speed, abrasive grit, and head retention force to achieve an effective yet gentle filing experience across multiple age groups.

Prototype RPM Testing

First Looks-Like Prototype

First Case Form Prototype

Case Touchpoint Brainstorming

Engineering Validation

Head Retention

Measured attachment and pull-off forces to ensure the sanding heads were easy for an adult to replace while remaining securely attached during use.

Device Logic and Rotation

Evaluated button behavior, speed progression, indicator feedback, and rotation direction to create an intuitive user experience and effective filing performance.

Case Opening Force

Tested opening and closing forces to balance secure retention during travel with easy one-handed access.

Engineering Builds

Reviewed successive engineering builds to identify performance, assembly, cosmetic, and manufacturing issues, then incorporated findings into each design iteration before production validation.

Head Retention Testing

Device Logic and Rotation

Case Opening Force Testing

Engineering Build Review

Outcome

Market Reception

★ 4.4 / 5 Average Rating

3,500+ Reviews on Amazon

Amazon’s Choice

Engineering Impact

Successfully launched into high-volume production by translating user insights into engineering requirements, optimizing for manufacturability, and reducing development risk through iterative prototyping and validation.

My Contributions

  • End-to-end mechanical engineering ownership

  • Cross-functional technical leadership

  • Co-development with vendor electrical engineering

  • Injection molded plastic design

  • Design for Manufacturing (DFM)

  • Engineering validation & prototype testing

  • High-volume production launch