The safety pin is one of those everyday objects we use without thinking twice. But if you’ve ever taken a closer look, you might have noticed a small hole in the coiled spring section of the pin, near the clasped end. It’s not a defect, nor is it decorative — it’s actually a clever piece of engineering. Here’s what that little hole is really for.
Invented in the 19th century, the safety pin relies on a simple yet efficient mechanism:
A curved metal shaft
A spring-like coil that creates tension
A protected point that keeps users from getting pricked
The coil is what keeps the shaft under pressure, ensuring the pin stays securely closed.
That small hole — often placed at the center of the spiral — is not random. It’s a functional feature used during the manufacturing process, and it plays a role in the pin’s long-term performance.
The hole allows the metal wire to be firmly secured in place, which helps:
Prevent the wire from unraveling or slipping
Maintain consistent tension in the spring mechanism
Ensure balanced pressure when the pin is closed
During production, the hole acts as an anchoring point while machines bend and form the pin. It helps manufacturers precisely position and fix the metal shaft before attaching the protective clasp and sharp point.
Without this small hole, the safety pin would:
Be less stable and more prone to accidental opening
Lose tension over time, reducing its reliability
Possibly fall apart with repeated use
So while barely noticeable, this tiny hole ensures the safety pin remains secure, functional, and durable — all while blending into the design.
In summary, the hole in the coil of a safety pin is a smart and essential design feature that helps keep the pin strong and reliable. A perfect reminder that even the simplest objects are often crafted with hidden precision.
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