Ben Kokes wanted to give a ring to his sweetheart, and to make it interesting, he decided to create a ring with an inductive loop that would cause the stones to light up when they were close to a power-source. He documented the tricky technical problems that cropped up during the build, and it sounds like the romance part came out well, too:
The final idea was to embed a LED and copper coil assembly inside the titanium ring, illuminating it from under the stones when it was in close proximity to an induced alternating magnetic field (henceforth called 'the transmitter'). Autodesk Inventor helped me develop all of the dimensions and constraints for the design. Having some help, I was able to obtain her ring size and the rest of the measurements were based from there (15.72mm if anyone was wondering)...
Of all the challenges presented in making the ring, affixing the stone is the most difficult. Traditionally, stones are affixed by mechanical means -- prongs, groves or snaps. Epoxies will delaminate from the attachment surfaces due to microstresses, thermal cycling, and other unmentioned movements. The stone may be attached now, but eventually it will fall out. It's just a matter of time.
With that in mind, I had 4 initial ideas for affixing the stone: thermally expanding the hole, hole deformation, point expansion deformation, and epoxy. Ultimately, I went with the epoxy method for attaching the stones.
The first test was to try and heat the ring, expand the hold and drop in the stone. When the hole cooled and contracted, it would hold the stone in place. Not only does the hole not expand enough, if I was lucky enough for it to happen (it did once), the stone would fracture along pre-existing crack lines.
(via Hacker News)
I’m making the final(ish*) stop of my Walkaway tour at Defcon this weekend in Las Vegas, giving a speech on Saturday in Track 2 at 10AM called $BIGNUM steps forward, $TRUMPNUM steps back: how can we tell if we’re winning?, followed by a book-signing at the No Starch Press table in the exhibitors’ hall.
In Paper Girls, the celebrated comics creator Brian K Vaughan (Saga, Y: The Last Man, etc) teams up with Cliff Chiang to tell a story that’s like an all-girl Stranger Things, with time-travel.
Ladder lockdown is a metal tray with super-grippy patches on its underside; set it down on any surface (including ice!) and then set your ladder’s feet in the tray and cinch it in place and the ladder won’t “kick out” and injure you and your loved ones.
If you often find yourself far away from AC power, or just want to guarantee that you’ll have GPS access on your next camping trip, the SolarJuice External Solar Battery is an excellent companion for outdoor adventures. It’s currently available in the Boing Boing Store for $59.99.The SolarJuice has a 26,800 mAh battery capable of […]
Between election hacks, ransomware, and Devil’s Ivy, the cybersecurity space is booming as malware and hackers become more sophisticated. If you’re interested in pursuing a career in ethical hacking, or just want to secure your own devices, The Super-Sized Ethical Hacking Bundle is a great resource.In this bundle, you’ll learn the fundamental skills of ethical hacking, prepare […]
The TREBLAB X11 Earphones are versatile, offer great sound, and are currently $32.99 in the Boing Boing Store.These Bluetooth earbuds are a great workout companion. They’re totally sweat proof and their ear-fins keep them snugly in place during high activity — something that Apple’s AirPods can only do if you were blessed with precisely the […]