Infinite Flying Glider

If you’ve exhausted your list of electronics projects over the past several weeks of trying to stay at home, it might be time to take a break from all of that and do something off the wall. [PeterSripol] shows us one option by building a few walkalong gliders and trying to get them to fly forever.

Walkalong gliders work by following a small glider, resembling a paper airplane but made from foam, with a large piece of cardboard. The cardboard generates an updraft which allows the glider to remain flying for as long as there’s space for it. [PeterSripol] and his friends try many other techniques to get these tiny gliders, weighing in at around half a gram, to stay aloft for as long as possible, including lighting several dozen tea candles to generate updrafts, using box fans, and other methods.

If you really need some electricity in your projects, the construction of the foam gliders shows a brief build of a hot wire cutting tool using some nichrome wire attached to a piece of wood, and how to assemble the gliders so they are as lightweight as possible. It’s a fun project that’s sure to be at least several hours worth of distraction, or even more if you have a slightly larger foam glider and some spare RC parts.

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CNC Hot-Wire Cutter Gives Form To Foam

Rapid prototyping tools are sometimes the difference between a project getting off the ground and one that stays strictly on paper. A lightweight, easy-to-form material is often all that’s needed to visualize a design and make a quick judgment on how to proceed. Polymeric foams excel in such applications, and a CNC hot-wire foam cutter is a tool that makes dealing with them quick and easy.

We’re used to seeing CNC machines where a lot of time and expense are put into making the frame as strong and rigid as possible. But [HowToMechatronics] knew that the polystyrene foam blocks he’d be using would easily yield to a hot nichrome wire, minimizing the cutting forces and the need for a stout frame. But the aluminum extrusions, 3D-printed connectors. and linear bearings he used still make for a frame stiff enough to give clean, accurate cuts. The addition of a turntable to the bed is a nice touch, turning the tool into a 2.5D machine. The video below details the construction and goes into depth on the toolchain [HowToMechatronics] used to go from design to G-code, including the tricks he used for making a continuous path, as well as integrating the turntable to make three-dimensional designs.

Plenty of hot-wire foam cutters have graced our pages before, everything from tiny hand-held cutters to a hot-wire “table saw” for foam. We like the effort put into this one, though, and the possibilities it opens up.

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Things Learned From Hot Wire Cutting A Droid’s Body

One of [Bithead]’s passions is making Star Wars droids, and in the process of building the outer shell for one of them he decided to use hot wire foam cutting and make his own tools. Having the necessary parts on hand and having seen some YouTube videos demonstrating the technique, [Bithead] dove right in. Things didn’t go exactly to plan but happily he decided to share what did and didn’t work, and in the end the results were serviceable.

[Bithead] built two hot wire cutters with nichrome wire. The first was small, but the second was larger and incorporated some design refinements. He also got an important safety reminder when he first powered on with his power supply turned up too high; the wire instantly turned red and snapped with an audible bang. He belatedly realized he was foolishly wearing neither gloves nor eye protection.

When it came to use his self-made tools, one of the biggest discoveries was that not all foam is equal in the eyes of a hot wire cutter. This is one of those things that’s common knowledge to experienced people, but isn’t necessarily obvious to a newcomer. A hot wire cutter that made clean and effortless cuts in styrofoam did no such thing with the foam he was using to cast his droid’s outer shell. Still, he powered through it and got serviceable results. [Bithead]’s blog post may not have anything new to people who have worked with foam and hot wire cutters before, but if you’re new to such things you can use it to learn from his experiences. And speaking of improving experiences, [Bithead] most recently snazzed up the presentation of his R2-D2 build by getting tricky with how he hides his remote control.

Piles Of Foam With A Hot Wire Slicer

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There are a million things you can do with foam, from some very impressive RC airplanes, all the way up to full-scale planes you can fly off into the wild blue yonder. Cutting foam, though, that’s a problem, and your best option is usually a hot wire foam cutter. [Darcy] put up some plans for a very nice bow cutter, but there’s also some experimentation for a foam slicer – a hot wire machine that takes a foam part and slices it like a smokehouse ham.

The bow-style cutter features laser cut parts, a pair of 1/4-20 bolts, a power supply, and about a foot of nichrome wire. It’s the bare minimum for cutting foam, but it seems to work really, really well.

The hot wire foam slicer is a much more interesting contraption, capable of making multiple thin sheets out of foam. Basically, it’s a laser cut tray with a bolt hole pattern running along the sides. Put two bolts along the side, loop some nichrome wire around the screw flights, and you have a way to cut foam in thicknesses of about 1/20th of an inch. Great if you’re trying to skin a model in very thin depron, or you just can’t find the right thickness of foam for your project.

CNC Hot Wire Cutter From Scanners

hot-wire-cutter-from-scanners

[Raul] built a CNC hot wire cutter that he uses for cutting shapes out of foam. His device uses two flat bed scanners to provide two planes of motion. One scanner arm has the foam mounted on it and provides the Y-axis movement. The other scanner has the hot wire mounted on it and provides the X-axis movement. The cutting wire is mounted on a flexed bow made from heavy gauge coat hanger wire.

He tapped into the logic board of one scanner to gain access to the motor movements. The other is connected through a couple of H-bridges. Both are controlled by an Atmel AVR ATmega128 which in turn takes its commands from a connection with a computer printer port. A python program uses vector graphic files in SVG format and traces the outline for cutting.

We’ve got a video of this in action after the break. At our request, [Raul] took some time to post a set of pictures and make comments on them. Thanks for the hard work and great job! Continue reading “CNC Hot Wire Cutter From Scanners”