Mirror, Mirror On The Wall, Do My Eyes Deceive Me After All

Say what you will about illusions, [Create Inc] has some 3D prints that appear to change shape when viewed in a mirror. For example, circles transform into stars and vice versa. A similar trick was performed by [Kokichi Sugihara] in 2016, where he showed circles that appear as squares in the mirror. For the trick to work, the camera’s position (or your eye) is important as the shapes look different from different angles. The illusion comes in when your brain ignores any extra information and concludes that a much more complex shape is a simpler one. [Create Inc] walks you through the process of how the illusion works and how it was created in Blender.

When he posted the video on Reddit, most seemed to think that it wasn’t a mirror and there was some camera trickery. At its heart, this is reverse-engineering a magic trick, and we think it’s an impressive one. STL files are on Thingiverse or Etsy if you want to print your own. We covered a second illusion that [Kokichi] did that relies on a similar trick.

Continue reading “Mirror, Mirror On The Wall, Do My Eyes Deceive Me After All”

RC Snowmobile Makes Tracks On Ice

With all the futuristic technology currently at our disposal, it seems a little bizarre that most passenger vehicles are essentially the same thing that they were a century ago. Four wheels, a motor, and some seats would appear to be a difficult formula to beat. But in the 3D printing world where rapid prototyping is the name of the game, some unique vehicle designs have been pushed out especially in the RC world. One of the latest comes to us from [RCLifeOn] in the form of a single-wheeled RC snowmobile.

While not a traditional snowmobile with tracks, this one does share some similarities. It has one drive wheel in the back printed with TPR for flexibility and it also includes studs all along its entire circumference to give it better traction on ice. There are runners in the front made from old ice skates which the vehicle uses for steering, and it’s all tied together with an RC controller and some lithium batteries to handle steering and driving the electric motor.

There were some design flaws in the first iteration of this vehicle, including a very large turning radius, a gearing setup with an unnecessarily high torque, and a frame that was too flexible for the chain drive. [RCLifeOn] was also testing this on a lake which looked like it was just about to revert to a liquid state which made for some interesting video segments of him retrieving the stuck vehicle with a tree branch and string. All in all, we are hopeful for a second revision in the future when some of these issues are hammered out and this one-of-a-kind vehicle can really rip across the frozen wastes not unlike this other interesting snowmobile from a decade ago.

Continue reading “RC Snowmobile Makes Tracks On Ice”

Filament Dry Box Design Goes Way Over The Top

There’s a fine line between simple feature creep and going over the top when it comes to project design. It’s hard to say exactly where that line is, but we’re pretty sure that this filament dry box has at least stepped over it, and might even have erased it entirely.

Sure, we all know the value of storing 3D printer filament under controlled conditions, to prevent the hygroscopic plastics from picking up atmospheric moisture. But [Sasa Karanovic] must really, REALLY hate the printing artifacts that result. Starting with a commercially available dry box that already had a built-in heating element, [Sasa] took it to the next level by replacing the controller and display with an ESP32. He added a fan to improve air circulation inside the enclosure and prevent stratification, as well as temperature and humidity sensors. Not satisfied with simply switching the heating element on and off at specific setpoints, he also implemented a PID loop to maintain a constant temperature. And of course, there’s a web UI and an API available for third-party control and monitoring.

The video below details [Sasa]’s design thoughts and goes into some detail on construction and performance. And while we may kid that this design is over-the-top, what really comes through is that this is a showcase for design ideas not only for one application, but for hardware projects in general. There are certainly simpler heated dry box designs, and zero-cost solutions as well, but sometimes going overboard has its own value too.

Continue reading “Filament Dry Box Design Goes Way Over The Top”

Printing Magnets

A research center in Spain has been working on ways to solve recent supply chain issues. One of these issues is a shortage of materials to make magnets. Their answer? Recycle ferrite residue by treating it and mixing it with ABS for 3D printing.

The mixing of ferrite with a polymer isn’t the key though, instead the trick is in the processing. The team collected strontium ferrite waste and ground it to a powder. Heating to the point of calcination (about 1000C) creates a superior material with a 350% increase in coercitivity and a 25% increase in remanence over the original waste material.

Continue reading “Printing Magnets”

3D Printing Tiny Metal Parts

It may sound like a pop band, but μ-WAAM is actually a 3D printing technique for making small metal parts from the NOVA University Lisbon. Of course, WAAM stands for wire arc additive manufacturing, a well-known technique for 3D printing in metal. The difference? The new technique uses 250 μm wire stock instead of the 1mm or thicker wires used in conventional WAAM.

The thinner feed wire allows μ-WAAM to create fine details like thin walls that would be difficult to replicate with traditional methods. Typically, for fine structures, printers use fused metal powder. This is good for fine details, but typically slower and has higher waste than wire-based systems.

Continue reading “3D Printing Tiny Metal Parts”

Complicated Calculated Solution To 3D-Printed Puzzle

3D printers have made a lot of things possible that were either extremely difficult or downright impossible with traditional tooling. Certain shapes lend themselves to 3D printing, and materials and tooling costs are also generally greatly reduced as well. One thing that may not be touched on as often, though, is their ability to rapidly prototype solutions to complex mathematical problems, in this case taking the form of a 3D printed maze, known as a dodecahedral holonomy maze, with an interesting solution.

The puzzle presents itself as a sphere composed of various inlaid hexagons which form a track for the puzzle piece, or “rook”. The tracks create the maze for the rook to travel, as some paths are blocked when the rook is oriented in certain ways. To solve the puzzle, the player must rotate the rook by moving it around the hexagons in such a way that its path isn’t physically blocked by any of the pegs in order to successfully reach the exit. This might seem like a fun toy to have on its surface, but the impressive thing about this is that the solutions are designed to reduce the likelihood of solving the puzzle with any “brute force” methods while at the same time having more than one path that will reach the exit as well as several bottlenecks that the puzzle solver must traverse as well.

There are actually many possible puzzles that can be produced in this size and shape, and all have predetermined solutions with cleverly chosen paths. This might seem like a lot but when you realize that the entire build from concept to 3D modeling to implementation was done by [Henry Segerman] and a group of other mathematicians at Oklahoma State University it starts to become more clear how the puzzle was so well-designed. In fact, we’ve featured some of his other mathematically-modeled builds in the past as well.

Thanks to [Inne] for the tip!

Continue reading “Complicated Calculated Solution To 3D-Printed Puzzle”

Pump Up The Resin

Sometimes the best ideas are simple and seem obvious after you’ve heard them. [Danny] showed us a great idea that fits that description. He uses a peristaltic pump to move resin in and out of his print bed. (Video, embedded below.) Normally, you remove the tank and pour the resin out into a container. With the pump, you can leave the tank where it is and simply pull the resin through a tube. The process is slower than pouring, but not as messy and doesn’t risk damage to your FEP film.

You can also use the pump like a vacuum to clean up resin. According to [Danny], the biggest value is when working with very large printers. He shows a Peopoly Phenom which has a huge tank compared to the other printers he shows in the video.

Continue reading “Pump Up The Resin”