What’s a “living hinge?”
Take a closer look at the image above. Notice how the entire contact lens basket is designed as one single piece? No loops, no pins. Minimal design perfection.
How does it work? Meet the “Living Hinge.”
I mentioned in a previous post that the Visonic Dome baskets are made of Polypropylene plastic. There are a ton of benefits of using this material, like bacterial resistance and non-toxicity. But today, I want to talk about one specific advantage of Polypropylene: its flexibility.
A traditional hinge has a loop and a pin. The pin rotates inside the loop as your door swings open and closes. Great for doors, but maybe not ideal for something as small as a contact lens cleaner.
Unlike the hinges you might find on your front door or on a cabinet, a Polypropylene living hinge has no moving parts. What it boils down to is this: a living hinge is a flexible strip of plastic that’s so elastic that it won’t break or deform even when bent past 180 degrees.
Living hinges are all around us when we know what to look for. An example that most of us are familiar with is the top of a ketchup bottle. It’s the strip of flexible plastic that joins the top of the lid to the bottle. Some toothpaste tubes use this design, too.
The most minimalist hinge for a minimalist design
Every time you add a moving part, you introduce wear and tear to your design. Cabinet doors become squeaky. Your front door doesn’t open as smoothly after years of use.
That doesn’t happen with a living hinge. These are designed (and tested!) to last through hundreds of thousands or even a million uses. It will easily last as long as any other component in the device. So it lasts practically forever.
Another benefit of the living hinge is that it’s all one piece. Traditional hinges are made of multiple parts that have to be assembled, often by hand. But that’s not the case with a living hinge. The whole thing, left and right baskets together, is made at the same time. That cuts down on production costs by reducing assembly time. The whole things just pops out of the injection mold ready to go.
A more perfect design
Every time I look at my dad’s ultrasonic contact lens cleaner design, I find another detail. Another key to his story. Sometimes the details are obvious, staring me right in the face. Like, why is it this color? Or that shape? Or this size?
But some of his design decisions are hiding a little deeper. And each time I discover one it feels like I’m learning something new about him and his process.
One of those design details is in these baskets and their beautifully simple living hinge.
It’s a design that’s so elegant, so simple, that you could use it a million times and never notice. Literally!
The most brilliant things are often like that, you know. They’re so perfect that you can’t imagine them being any other way.
But the funny thing is, they weren’t always this way! Simple designs like these aren’t created overnight.
If you look at the photo of his original Visonic Dome above, you’ll see that the basket design was very different. My dad called this iteration the “butterfly basket.” The reference being the way that the baskets open mimics butterfly wings.
It was an interesting piece of engineering. Multiple hinges. Kind of complicated. And it’s made of at least three different moving parts.
Over the years, my dad whittled away at his design and perfected it. He maintained the original silhouette while improving his production methods and upgrading little things like this.
I just wanted to show you this evolution because I think it’s an aspect of design that’s not often highlighted. Things don’t have to be perfect the first time. The key is to keep a critical eye, keep learning, and to improve as you go.
“The definition of genius is taking the complex and making it simple.”
Albert Einstein
