What’s the thinnest nominal wall thickness you’ve ever injection molded?
And what about 0.2 mm (yes, nominal)?
Here’s a case study we’ve prepared just for you!
A few years ago, we worked on a product that was essentially an AirTag (before such a thing even existed), called Pixie Tags.
Using a phone app, users could locate the object the tag was attached to.
These tags function as part of an ecosystem in the world of “Digital Location of Things”.
As part of the design brief, we aimed to create the thinnest product possible. Ideally, we’d all prefer locator stickers over tags.
Our control over the product’s thickness was based on electronics and energy component arrangement and wall thickness of the plastic housing.
We sought reference products with thin-walled enclosures manufactured at a mass production scale.
We found the perfect example in SD memory cards.
The need to increase memory capacity within a fixed-sized card challenged not only flash memory miniaturization but also the enclosure developers.
The thinner the wall, the larger the internal volume.
This led to the development of specialized raw materials with improved flow properties, and electric injection molding machines instead of hydraulic ones.
Electric machines allow for higher injection speeds than usual, with an accuracy of 0.01 mm.
These machines enable wall thicknesses as thin as 160 microns (or 0.16 mm, for those thinking in millimeters).
Thin-wall plastic design differs from conventional nominal design principles.
At such thin wall thicknesses, there’s no need to maintain rib-to-wall ratios, and it’s possible to design ribs and snaps at nominal thickness without worrying about sink marks.
And as always, we weren’t alone in this process.
Giora Sussmann, the visionary from Pixie Technology, Hanan Anderman, who knows plastics down to the molecular level, two brave individuals, and of course, T-1 product development, who brought the vision to life.
Feel free to check out the results in the photos and share your thoughts!
