Not a Pot, Not an Encoder: Exploring Synchros for Rotational Sensing

We’re all familiar with getting feedback from a rotating shaft, for which we usually employ a potentiometer or encoder. But there’s another device that, while less well-known, has some advantages …read more Continue reading Not a Pot, Not an Encoder: Exploring Synchros for Rotational Sensing

Magnetic Angle Sensor Mods Make Encoder Better for Blasting

Most of the hacks we see around these parts have to do with taking existing components and cobbling them together in interesting new ways. It’s less often that we see existing components gutted and repurposed, but when it happens, like …read more

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Specialized Knife Sharpener from Old Airplane

“Surely sharpening a knife can’t be that hard” one might think, as they destroy the edge on their pocket knife by flailing it wildly against a whetstone of indeterminate grain. In reality, knife sharpening is as nuanced a practice as virtually any other field, and getting a quality finish is much harder than it seems. It also gets increasingly complex with different blades, as [Turbo Conquering Mega Eagle] shows with is customized knife sharpening jig.

The hardest part in any blade sharpening is getting the proper bevel angle. A heavy angle is good for heavy-duty tools like axes, but for …read more

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A Polar Coordinate CNC Plotter Even Descartes Could Love

Take apart a few old DVD drives, stitch them together with cable ties, add a pen and paper, and you’ve got a simple CNC plotter. They’re quick and easy projects that are fun, but they do tend to be a little on the “plug and chug” side. But a CNC plotter that uses polar coordinates? That takes a little more effort.

The vast majority of CNC projects, from simple two-axis plotters to big CNC routers, all tend to use Cartesian coordinate systems, where points on a plane are described by their distances from an origin point on two perpendicular axes. …read more

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Mechanisms: The Screw Thread

They hold together everything from the most delicate watch to the largest bridge. The world is literally kept from coming apart by screws and bolts, and yet we don’t often give a thought to these mechanisms. Part of that is probably because we’ve gotten so good at making them that they’re seen as cheap commodities, but the physics and engineering behind the screw thread is interesting stuff.

We all likely remember an early science lesson wherein the basic building blocks of all mechanisms laid out. The simple machines are mechanisms that use an applied force to do work, such as …read more

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Hacked Car Axle Yields Custom 90° Gearbox

Need a sturdy angle gearbox to handle power transmission for your next big project? Why not harvest a rear axle from a car and make one yourself?

When you think about it, the axle of a rear-wheel drive vehicle is really just a couple of 90° gearboxes linked together internally, and a pretty sturdy assembly that’s readily available for free or on the cheap. [Donn DIY]’s need for a gearbox to run a mower lead him to a boneyard for the raw material. The video below shows some truly impressive work with that indispensable tool of hardware hackers, the angle …read more

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A CNC You Could Pop-Rivet Together

You have to be careful with CNC; it’s a slippery slope. You start off one day just trying out a 3D printer, and it’s not six months before you’re elbow deep in a discarded Xerox looking for stepper motors and precision rods. This is evident from [Dan] and his brother’s angle aluminum CNC build.

Five or six years ago they teamed up to build one of those MDF CNC routers. It was okay, but really only cut foam. So they moved on to a Rostock 3D printer. This worked much better, and for a few years it sated them. However, …read more

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