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’ve been noting humorous updatings of Ambrose Bierce’s 1906 humor classic The Devil’s Dictionary for years — there was the publishing edition, and this corker on copyright — but the Educational Technology edition, by New Storytelling author Bryan Alexander has a currency and an urgency that scores an acerbic bullseye.
Daily Show writer Daniel Radosh’s son came home from school with a permission slip that he’d have to sign before the kid could read Ray Bradbury’s novel Fahrenheit 451, which is widely believed to be an anti-censorship book (Bradbury himself insisted that this was wrong, and that the book was actually about the evils of […]
The Nightmare Machine is an MIT project to use machine learning image-processing to make imagery for Hallowe’en.
Geek Fuel is a subscription delivery service that caters to those of us that love comics, gaming, and general geek culture. Every month, Geek Fuel will assemble a box of goodies with a value of $50 or over. The specific items are a mystery, but you’ll always get an exclusive t-shirt not found anywhere else, a full […]
If you like to DIY and you like helicopters, you’re going to really love the Flexbot Hexacopter Kit. This copter blows traditional models out of the water: it includes everything you need to actually build your own hexacopter, and then pilot it like a pro, too.The construction is complicated enough to give you a challenge, […]
This week’s top deals from the Boing Boing Store range from lobster to wine to desk organization. 1. Get Maine Lobster (50% Off)With these discounted packages from Get Maine Lobster, you can experience the sweet, fresh flavor of world-renowned Maine lobster right at your own dinner table. There are four options to choose from, each at […]