3D-printed wall builder, circa 1930s

Retrotechtacular: 3D-Printed Buildings, 1930s Style

Here we are in the future, thinking we’re so fancy and cutting edge with mega-scale 3D printers that can extrude complete, ready-to-occupy buildings, only to find out that some clever inventor came up with essentially the same idea back in the 1930s.

The inventor in question, one [William E. Urschel] of Valparaiso, Indiana, really seemed to be onto something with his “Machine for Building Walls,” as his 1941 patent describes the idea. The first video below gives a good overview of the contraption, which consists of an “extruder” mounted on the end of a counterweighted boom, the length of which determines the radius of the circular structure produced. The boom swivels on a central mast, and is cranked up manually for each course extruded. The business end has a small hopper for what appears to be an exceptionally dry concrete or mortar mix. The hopper has a bunch of cam-driven spades that drive down into the material to push it out of the hopper; the mix is constrained between two rotating disks that trowel the sides smooth and drive the extruder forward.

The device has a ravenous appetite for material, as witnessed by the hustle the workers show keeping the machine fed. Window and door openings are handled with a little manual work, and the openings are topped with lintels to support the concrete. Clever tools are used to cut pockets for roof rafters, and the finished structure, complete with faux crenellations and a coat of stucco, looks pretty decent.

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Box Forts For Adults: Best Practices And Design Strategies

Many a grown up can reminisce about building various architectural wonders in their youth. Forts, whether based on boxes or blankets, were the order of the day, and an excellent way to spend a rainy Sunday afternoon.

It just so happens that there is no law against scaling up such activities once one has reached the age of majority. However, to build a structure at this level takes some careful planning and consideration, and that is the purpose of our article here today.

Location, Location, Location

To avoid an awkward conflict, be sure to warn your housemates of impending construction well ahead of time.

The first major consideration when starting your build should be the area in which you wish to do it. Building inside has the advantage of avoiding the weather, however hard floors can lead to sore knees when crawling around. Additionally, you’re a grown up now, so it’s less likely your peers will be impressed to hear you sat inside a box in your living room.

No, if you’re going to do this right, you’ll want to go outside. A nice flat lawn is best, providing soft ground and plenty of space. The challenges of the elements will guide your work – sitting inside your cardboard home feels all the more satisfying when you’re cosy and dry as you listen to the patter of rain on the roof. There’s a real sense of accomplishment when you’ve built something that can survive the harsh outdoors, and besides, the views are better, too. Continue reading “Box Forts For Adults: Best Practices And Design Strategies”

Star Trek Material Science Is Finally Real: Transparent Wood

It’s not transparent aluminum, exactly, but it might be even better: transparent wood. Scientists at the University of Maryland have devised a way to remove all of its coloring, leaving behind an essentially clear piece of wood.

IMG_20160518_110605By boiling the block of wood in a NaOH and Na2SO chemical bath for a few hours the wood loses its lignin, which is gives wood its color. The major caveat here is that the lignin also gives wood strength; the colorless cellulose structure that remains is itself very fragile. The solution is to impregnate the transparent wood with an epoxy using about three vacuum cycles, which results in a composite that is stronger than the original wood.

There are some really interesting applications for this material. It does exhibit some haze so it is not as optimally transparent as glass but in cases where light and not vision is the goal — like architectural glass block — this is a winner. Anything traditionally build out of wood for its mechanical properties will be able to add an alpha color channel to the available options.

The next step is finding a way to scale up the process. At this point the process has only been successful on samples up to 1 centimeter thick. If you’re looking to build a starship out of this stuff in the meantime, your best bet is still transparent aluminum. We do still wonder if there’s a way to eliminate the need for epoxy, too.

Scrolling A Message On A Building In A Time Lapse Video

[Saulius Lukse] has a really interesting way of turning a couple of buildings into his own addressable display. The effect is not seen in real life, but is a clever video rendering with stock he pulled from time-lapse cameras. Now if you want to play Tetris using the windows of a building you add wireless lightbulbs to every window. But that’s a lot of work. You can fake playing Tetris (or scrolling messages in this case) if you just show a video of the buildings and swap in your own image manipulation.


[Saulius] starts with a time lapse sequence of a city scape. It needs to be one with a large building or two to provide a good scrolling surface. The building is extracted from the scene with the background transparent. The really time consuming part is creating a distinct image with one window lit for each window that is going to be used. This set of windows are the ‘pixels’ used to create the scrolling images. This is accomplished by masking out one image of the building with every office light turned off, then masking out each window individually with the office illuminated. This masking means everything going on around the building (traffic, weather, people) will be preserved, while the windows can be individually manipulated.

Next the program jinx is used to create the building animation. This program is designed to create scrolling messages on LED panels. [Saulius] provides a Python script that takes the images, the output of jinx, and combines them to create the final set of moving images.

The result is a city wishing you a “Happy New Year!”

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Building Things With Lean Pipe

Sometimes you just want to build something quickly and easily. Maybe you just need a basic structure for your actual project, or perhaps you want to be able to easily modify the design. Maybe you don’t have access to many fancy tools to build a solid, lightweight structure. Another possibility is that you want to be able to break down your structure and move it at a later date. In cases like these, you might want to consider using lean pipe.

Lean pipe is kind of like K’NEX for adults. It’s made up of metal pipe and specialized fittings. If you’ve ever worked with PVC pipe before then this may sound familiar. The difference is lean pipe is stronger and designed specifically for building sturdy structures. The fixtures designed for use with lean pipe are much easier to work with than PVC pipe. With PVC pipe, it seems like you never have the exact right fitting and you have to build your own adapters, quickly increasing the cost of the design.

A typical lean pipe fitting will either slide over the end of a section of pipe, or wrap around it somewhere in the middle. An adjustment screw can then be tightened to clamp the fitting in place around the sections of pipe. The video below does a good job demonstrating the different possibilities with fittings. The primary issue with this material is that you might not be able to find it at your local hardware store. Luckily, a quick Internet search will turn up a number of online purchasing options.

So what can you build with this stuff? Cody has been building himself computer desks with an industrial look. He first starts out with the frame design. This is the part that’s made from the lean pipe. Once the frame is completed he just needs to work on the wood surfaces. All he really needs to do is cut the wood to shape and then finish it to look nice. It then lays in place and can be bolted down for extra security. Continue reading “Building Things With Lean Pipe”

Skyscraper Tetris Lets The City Know How Good Or Bad You Are

If you’ve clocked one-too-many hours at Tetris, it might be time to show the world your skills on this skyscraper-sized display on the Shell Centre in London. [Benjamin], [Tom], and their “army of volunteers” took to the Shell building and assembled their super-screen from a collection of 182 networked wireless lightbulbs, some tracing paper, and mylar to create a playable interface from the Jubilee Gardens below.

[Benjamin] doesn’t deliver many of the technical details on his post, but he does give us an overview. He achieves full wireless coverage of all floors by spacing out 14 TP-Link WR702n routers, each running the same version of OpenWRT. This interface wasn’t [Benjamin’s] first choice, as he would’ve preferred to tap into the building’s existing wireless network; unfortunately, he was left without support from the building’s network team. Equipped with a large donation of wireless bulbs controlled by a central bridge, [Benjamin’s] Python-adaptation of Tetris can refresh the building about about 1-to-2 frames per second. Given his description of the bulb interface, we suspect he’s using the all-too-familiar Philips Hue smart lightbulbs to illuminate the building.

In case you haven’t heard of Faraday’s Christmas Lectures, they’re the UK’s nationally broadcasted “science special” featured at the end of the year and founded in 1825 by [Michael Faraday] himself. The goal of these Lectures is to introduce young people to some aspect from the sciences. We’ve seen giant Tetrises before, but not in a way that inspires such a young audience. We’re thrilled to see that hacking both in software (Python, LAN networks) and hardware (ZigBee, OpenWRT) made the cut for this year’s special. After all, why should MIT keep all the fun to themselves?

If the building-scale is just too big for your taste, why not have a go on your oscilloscope?

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Power Index Window Display Turns Buildings Into LED Matrices

What started off as a fun project using light bulbs picked up some sponsorship and is going on tour. This project now uses LED modules controlled on the 2.4 GHz band to turn buildings into full color displays. It’s the product of students at Wrocław University of Technology in Poland. The group is something of an extra-curricular club that has been doing this sort of thing for years. But now they’ve picked up some key sponsorships which not only allowed for upgraded hardware, but sent the group on a tour of Universities around Europe. Who would’ve thought you could go on tour with something like this?

Much like the MIT project we looked at in April, this lights up the dark rooms of a grid-like building. It does go well beyond playing Tetris though. The installation sets animations to music, with a custom animation editor so that you can submit your own wares for the next show. Don’t miss the lengthy performance after the break.

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