On the shortlist of dream tools for most metalworkers is a waterjet cutter, a CNC tool that uses insanely high-pressure water mixed with abrasive grit to blast sheet metal into intricate shapes. On exactly nobody’s list is this attachment that turns a waterjet cutter into a lathe, and with good reason, as we’ll see.
This one comes to us by way of the Waterjet Channel, because of course there’s a channel dedicated to waterjet cutting. The idea is a riff on fixtures that allow a waterjet cutter (or a plasma cutter) to be used on tubes and other round stock. This fixture was thrown together from scrap and uses an electric drill to rotate a wood blank between centers on the bed of the waterjet, with the goal of carving a baseball bat by rotating the blank while the waterjet carves out the profile.
The first attempt, using an entirely inappropriate but easily cut blank of cedar, wasn’t great. The force of the water hitting the wood was enough to stall the drill; the remedy was to hog out as much material as possible from the blank before spinning up for the finish cut. That worked well enough to commit to an ash bat blank, which was much harder to cut but still worked well enough to make a decent bat.
Of course it makes zero sense to use a machine tool costing multiple hundreds of thousands of dollars to machine baseball bats, but it was a fun exercise. And it only shows how far we’ve come with lathes since the 18th-century frontier’s foot-powered version of the Queen of the Machine Shop.
Continue reading “Turning A Waterjet Cutter Into A Wood Lathe, For No Reason”
We’ll be honest right up front: there’s nothing new in [David Cambridge]’s brushless motor and controller build. If you’re looking for earth-shattering innovation, you’d best look elsewhere. But if you enjoy an aimless use of just about every technique and material in the hacker’s toolkit employed with extreme craftsmanship, then this might be for you. And Nixies — he’s got Nixies in there too.
[David]’s build started out as a personal exploration of brushless motors and how they work. Some 3D-printed parts, a single coil of wire, and a magnetic reed switch resulted in a simple pulse motor that performed surprisingly well. This morphed into a six-coil motor with Hall-effect sensors and a homebrew controller. This is where [David] pulled out all the stops on tools — a lathe, a plasma cutter, a welder, a milling machine, and a nice selection of woodworking tools went into making parts for the final motor as well as an enclosure for the project. And because he hadn’t checked off quite all the boxes yet, [David] decided to use the 3D-printed frame as a pattern for casting one from aluminum.
The finished motor, with a redesigned rotor to deal better with eddy currents, joined the wood and metal enclosure along with a Nixie tube tachometer and etched brass control plates. It’s a great look for a project that’s clearly a labor of self-edification and skill-building, and we love it. We’ve seen other BLDC demonstrators before, but few that look as good as this one does.
Continue reading “Steampunk Brushless Motor Demo Pushes All The Maker Buttons”
When it comes to building materials, wood doesn’t always draw the most attention as the strongest in the bunch. That honor usually goes to concrete and steel – steel embedded in concrete provides support and a foundation for tall buildings, while concrete increases tensile strength and can be formed into a variety of shapes with the help of rebar. Wood, on the other hand, decays and is vulnerable to moisture damage and fire.
That’s not necessarily the case anymore, thanks to the development of advanced timber. New materials like glulam, or sheets of timber bonded with moisture-resistant structural adhesives, can be produced using two to three times less energy than steel, making them environmentally-friendly alternatives to other building materials. Granted, this requires the beams to be burned at the end of their lifespan, but glulam still has an equivalent or better environmental profile compared to steel, not to mention a lower cost.
Among engineered wood, there are some varieties more commonly used among hobbyists – MDF, plywood, or particle board for instance. Others, like Cross-Laminated Timber (CLT) are more common among building materials. While CLT buildings have existed for decades, recently major cities like Stockholm and Vancouver have seen a resurgence of timber construction. Since wood can theoretically store carbon for the entire length of its lifespan, up to 0.8 tons in a cubic meter of spruce, some architecture firms like Oslotre are building houses with a negative carbon footprint.
Projects like Sidewalk Labs and Masthamnen are proposing entire neighborhoods and skyscrapers built from advanced timber. Compared to International Style architecture, characterized by gray concrete, shiny metal, and glass, this movement could be a step towards returning to natural architectural forms. Given the stress reducing effects of green spaces in cities, engineered wood buildings could bridge the gap between modern architectural styles and natural woodlands.
Most computer case modders take certain liberties with their builds, to express their creativity and push the state of the art. Some, however, seek to recreate the original in as detailed a way as possible while still being unique. This faithful reproduction of a Commodore 64C in wood is a great example of the latter approach.
[Atilla Meric]’s experience with model airplane building came into play when he decided to leap into this build. Being used to making small, thin pieces of wood even smaller and thinner proved valuable here, as did working from templates and getting complex shapes cut out cleanly. [Atilla] used a miniature table saw to rough cut his stock; the wood species may have been lost in the translation from Turkish but it appears to be some variety of oak. Detail cuts were done with knives, and everything was held together with glue. The painstaking effort that went into the air vents is amazing, and the fact that they exactly match the vents on the original injection-molded case is truly impressive. We also like the subtle detail of the slightly depressed area around the keyboard opening, just like the original, as well as the smooth curve at the front of the case to comfortably support the wrists. The cutouts for connectors and the labels are top-notch too.
We appreciate the craftsmanship that went into this case mod, and the time and effort [Atilla] put into the build are obvious. We’ve seen wooden computer case mods before, but this one really pushes all our buttons.
Researchers have created an audio speaker using ultra-thin wood film. The new material demonstrates high tensile strength and increased Young’s modulus, as well as acoustic properties contributing to higher resonance frequency and greater displacement amplitude compared to a commercial polypropylene diaphragm in an audio speaker.
Typically, acoustic membranes have to remain very thin (on the micron scale) and robust in order to allow for a highly sensitive frequency response and vibrational amplitude. Materials made from plastic, metal, ceramic, and carbon have been used by engineers and physicists in an attempt to enhance the quality of sound. While plastic thin films are most commonly manufactured, they have a pretty bad impact on the environment. Meanwhile, metal, ceramic, and carbon-based materials are more expensive and less attractive to manufacturers as a result.
Cellulose-based materials have been making an entrance in acoustics research with their environmentally friendly nature and natural wooden structure. Materials like bagasse, wood fibers, chitin, cotton, bacterial cellulose, and lignocellulose are all contenders for effective alternatives to parts currently produced from plastics.
The process for building the ultra-thin film involved removing lignin and hemicellulose from balsa wood, resulting in a highly porous material. The result is hot pressed for a thickness reduction of 97%. The cellulose nano-fibers remain oriented but more densely packed compared to natural wood. In addition, the fibers required higher energy to be pulled apart while remaining flexible and foldable.
At one point in time, plastics seemed to be the hottest new material, but perhaps wood is making a comeback?
[Thanks Qes for the tip!]
Before graphic calculators and microcomputers, plotting functions were generally achieved by hand. However, there were mechanical graphing tools, too. With the help of a laser cutter, it’s even possible to make your own!
The build in question is nicknamed the Harmonic Analyzer. It can be used to draw functions created by adding sine waves, a la the Fourier series. While a true Fourier series is the sum of an infinite number of sine waves, this mechanical contraption settles on just 5.
This is achieved through the use of a crank driving a series of gears. The x-axis gearing pans the notepad from left to right. The function gearing has a series of gears for each of the 5 sinewaves, which work with levers to set the magnitude of the coefficients for each component of the function. These levers are then hooked up to a spring system, which adds the outputs of each sine wave together. This spring adder then controls the y-axis motion of the pen, which draws the function on paper.
It’s a great example of the capabilities of mechanical computing, even if it’s unlikely to ever run Quake. Other DIY mechanical computers we’ve seen include the Digi-Comp I and a wildly complex Differential Analyzer. Video after the break.
Continue reading “Harmonic Analyzer Does It With Cranks And Gears”
We’ve seen plenty of plywood 3D printers before; after all, many early hobbyist machines were made from laser-cut plywood. But this plywood 3D-printer isn’t made from plywood – it prints plywood. Well, sort of.
Yes, we know – that’s not plywood the printer is using, but rather particleboard, the same material that fills the flatpack warehouse of every IKEA store. And calling it a printer is a bit of a stretch, too. This creation, by [Shane Whigton] and his Formlabs Hackathon team, is more of a hybrid additive-subtractive CNC machine. A gantry-mounted router carves each layer of the print from a fresh square of material – which could just as easily be plywood as particleboard. Once a layer is cut, the gantry applies glue to it, puts a fresh sheet of material on top, and clamps it down tight. The router then carves the next layer, and so on up the stack. The layer height is limited to the thickness of the material – a nominal 3/4″ (19 mm) in this case – and there’s a remarkable amount of waste, but that’s not really the point. Check out the printer in action and the resulting giant Benchy in the video below.
Seeing all that particleboard dust and glue got us thinking: what about a 3D-printer that extrudes a paste of sawdust mixed with glue? We imagine that would be a bit like those giant printers that extrude concrete to build houses.
Continue reading “3D Printer Meets CNC Router To Make Wood Prints”