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)
The End of Trust (previously) is a special issue of McSweeney's, produced in collaboration with the Electronic Frontier Foundation, on the themes of technology, privacy and surveillance: it's in stores today, and free to download under a Creative Commons license.
Fantasy and science fiction author and political activist Steven Brust (previously) was this year's Guest of Honor at Philcon, an excellent Philadelphia-area science fiction (I have also had the privilege to be Philcon's GoH, and it's a great con); his guest of honor speech is entitled Truth as a Vehicle for Enhancing Fiction, Fiction as […]
$5 from the $17 purchase price of each hand-painted Trumpturd squishy is directed to the charity of your choice, from among the ACLU, Greenpeace, Planned Parenthood, or the Institute for Free Speech. (Thanks, Jared!)
The key to learning any new language is feedback. When you’re immersed in conversation, it’s easy to pick up key phrases and pronunciation, but not all of us have the means to jet off to Spain, France or wherever we can learn to speak like a local. The next best thing: The Mondly app. Mondly […]
Got a gadget-minded geek on your holiday list this year? Don’t wait for Black Friday. The prices are already dropping on some quality tech toys, and we’ve got a roundup of some of our favorites. Force Flyers DIY Building Block Drone MSRP: $49.99 | Normally: $42.99 | Price Drop: $39.99 (20% Off) Compatible with everybody’s […]
Ever wondered what it takes to make the transition from amateur photography to a full career? If you answered “a better camera,” you’re half right. Before you get the equipment, get the know-how to use it with the Hollywood Art Institute Photography Course & Certification. Taught by experienced pros, this course is geared towards shutterbugs […]