New (mis)Use For Lithophanes: Miniature Diorama Backgrounds

July 6, 2020 by Donald Papp 3 Comments

What’s better than a well-lit photo of a 3D-printed miniature? A photo of the miniature in a mini diorama, of course. [OrionDeHunter] shows off a clever technique that has something in common with old-timey photo stages and painted backgrounds, and (mis)uses 3D-printed lithophanes to pull it off. What [OrionDeHunter] does is use a curved and painted lithophane as a stand-in for a background, and the results look great!

Lithophanes are intended to be illuminated from behind to show an image, with thin areas showing as lighter and thicker areas darker, but when it comes to high contrast patterned images like brick walls, the same things that make a good lithophane just happen to also make a pretty good 3D model in the normal sense. No 3D scanning or photogrammetry required.

Here is the basic process: instead of creating a 3D model of a brick wall from scratch, [OrionDeHunter] simply converted an image of a brick wall (or stairs) into a curved lithophane with an online tool. The STL model of the lithophane is then 3D printed, painted, and used as a swappable background. When macro shots of the miniatures are taken, the curved background looks just right and allows for some controlled lighting. It’s a neat trick, and well applied in this project. Some sample images demonstrating how it works are just under the break.

A painted lithophane makes a convincing brick wall

Other images like these stairs can work, too.

Lithophanes were originally made using marble or thin porcelain, but a modern spin has been put on the technique with 3D printing. Enterprising hackers have even discovered ways to add color, too.

3D-Printing Bigger Wind Turbines

July 6, 2020 by Dan Maloney 66 Comments

Many decades ago, a much younger version of me was in the car with my dad and my brother, cruising down the highway on some errand or another. We were probably all in the front seat, and none of us were wearing seatbelts; those were simpler times. As we passed under an overpass, my dad said, “Do you know why the overpasses on these roads are so high?” Six-year-old me certainly didn’t, but it was clear dad did and had something to say about it, so we just shook our heads and waited for the lesson. “Because that’s how big nuclear missiles are.” He then went into an explanation of how the Interstate Highway System in the USA, then still in its infancy, was designed to make sure the armed forces could move around the country, so overpasses needed to allow trucks with big loads to pass.

It was an interesting lesson at the time, and over the years I’ve continued to be impressed with the foresight and engineering that went into the Interstate system here in the US. It’s far from perfect, of course, and it’s only recently that the specifications for the system have started to put a pinch on things that seem totally unrelated to overpass dimensions — namely, the size and efficiency of wind turbines.

Continue reading “3D-Printing Bigger Wind Turbines” →

The Spin Cycle: Washing Machine Motor Converts 10-Speed To E-Bike

July 6, 2020 by Bryan Cockfield 77 Comments

The “Spin Cycle” is an amazing electric bicycle built using a motor salvaged from a washing machine; when the puns are this perfect you have to roll with them. [jimminecraftguy’s] creation is one of the most hacked-together yet functional electric vehicle we’ve seen in a long time.

The drive train of this bicycle starts with a brushless DC motor from a washing machine. It has been slightly modified to run on 48 volts, and is installed inside the triangle of the bike’s frame. It has a chain driving the bike’s crank, retaining the original chain and gearing setup (unlike many electric bike hacks that utilize hub motors). The crank has also been specially modified to include a freewheel, a necessary feature so that the motor can operate without spinning the pedals. Everything except the motor has been custom fabricated including the mounts and the electronics.

[jimminecraftguy] reports speeds of 110 kph which is a little crazy for a 20-year-old aluminum frame bike, and we’d guess it’s not street legal in many jurisdictions, but we can’t really find much fault with this build in general based on the amount of innovation required to get this working at all. A few more improvements for the build are in the works, including improved batteries and a cover for the sides to keep the local law enforcement from getting too suspicious. We can’t wait to see the final version. Continue reading “The Spin Cycle: Washing Machine Motor Converts 10-Speed To E-Bike” →

Elegant Shoji Lamps From Your 3D Printer

July 6, 2020 by Tom Nardi 12 Comments

The gorgeous Shoji-style lamps you’re seeing here aren’t made of wood or paper. Beyond the LEDs illuminating them from within, the lamps are completely 3D printed. There aren’t any fasteners or glue holding them together either, as creator [Dheera Venkatraman] used authentic Japanese wood joinery techniques to make their components fit together like a puzzle.

While we’re usually more taken with the electronic components of the projects that get sent our way, we have to admit that in this case, the enclosure is really the star of the show. [Dheera] has included a versatile mounting point where you could put anything from a cheap LED candle to a few WS2812B modules, but otherwise leaves the integration of electronic components as an exercise for the reader.

All of the components were designed in OpenSCAD, which means it should be relatively easy to add your own designs to the list of included panel types. Despite the colorful details, you won’t need a multi-material printer to run them off either. Everything you see here was printed on a Prusa i3 MK3S in PETG. Filament swaps and careful design were used to achieve the multiple colors visible on some of the more intricate panels.

If the timeless style of these Japanese lanterns has caught your eye, you’ll love this beautiful sunrise clock we covered last year.