This year for Valentine’s Day we wanted to do something fun and out of the norm. So, I was challenged to model and 3D print a diamond ring. Go big or go home right? Forget the ring that Richard Burton bought for Elizabeth Taylor. We one-upped the Taylor-Burton ring by adding an RGB LED, because everything is better with “the blinkies”.
Creating the diamond in Autodesk Fusion 360 was easy, but deciding how to incorporate the batteries and switch so they were accessible, and figuring out how to connect the diamond with the ring portion was the challenge.
The diamond was drawn as a single round cut, hollowed out with a 10.75mm hole for the 10mm RGB cycling LED we selected to fit perfectly inside. The dual band is 5mm wide with a curved exterior. At the top of the ring is a flat piece to provide a surface to glue the centerpiece onto. The centerpiece is an oblong octagon shape. This was designed partially for decoration, but more so as a location to place the on/off switch and battery holder.
The diamond was printed in translucent “natural” colored PCTPE filament and the rest was printed in black PLA on a Lulzbot Mini2. The wiring was done along with placing the switch and battery holder in place and gluing them, then the LED was placed and all three separate portions were glued together.
The circuit has a simple construction. The battery holder was placed and the LED’s cathode was soldered directly to the battery holder’s negative lead. A wire was soldered and heatshrinked to the battery holder’s positive lead and then to the slide switch. The LED’s anode was then soldered directly to the “common” center contact of the switch.
A couple of modifications were made before we got to this revision. Initially the band was designed with a cutout for the battery to fit, but this gave us trouble trying to figure out a place to include a switch and isolate the LED leads from continually being in contact with the battery.
Once this ring design with the transitional piece was assembled, the ring ended up being too wobbly and lopsided due to the extreme size, so we added a secondary ring to help balance and keep it upright.
Overall I’m extremely pleased with the finished product. It is exaggerated and beautiful! So, if you’re looking for a humorous and fun gift to give someone this Valentine’s Day, this is the perfect solution. Find it here on Digi-Key's Thingiverse account. Happy Making!