A CNC Woodworking Tool That Does The Hard Parts

August 28, 2018 by Kerry Scharfglass 26 Comments

Drawn along in the wake of the 3d printing/home shop revolution has been the accessibility of traditional subtractive CNC equipment, especially routers and mills. Speaking of, want a desktop mill? Try a Bantam Tools (née Othermachine) Desktop Milling Machine or a Carvey or a Carbide 3D Nomad. Tiny but many-axis general purpose mill? Maybe a Pocket NC. Router for the shop? Perhaps a Shapeoko, or an X-Carve, or a ShopBot, or a… you get the picture. [Rundong]’s MatchSticks device is a CNC tool for the shop and it might be classified as a milling machine, but it doesn’t quite work the way a more traditional machine tool does. It computer controls the woodworker too.

At a glance MatchSticks probably looks most similar to a Pocket NC with a big Makita router sticking out the side. There’s an obvious X-axis spoilboard with holes for fixturing material, mounted to a gantry for Z-axis travel. Below the big friendly handle on top is the router attached to its own Y-axis carriage. The only oddity might be the tablet bolted to the other side. And come to think of it the surprisingly small size for such an overbuilt machine. What would it be useful for? MatchSticks doesn’t work by processing an entire piece of stock at once (that what you’re for, adaptable human woodworker) it’s really a tool for doing the complex part of the job – joinery – and explaining to the human how to do the rest.

The full MatchSticks creation flow goes like this:

Choose a design to make on the included interface and specify the parameters you want (size, etc).
The MatchSticks tool will suggest what material stocks you need, and then ask you to cut them to size and prepare them using other tools.
For any parts which require CNC work the tool will help guide the user to fixture the stock to its bed, then do the cutting itself.
Once everything is ready for final assembly the MatchSticks will once again provide friendly instructions for where to pound the mallet.

In this way [rundong], [sarah], [jeremy], [ethan], and [eric] were able to build a much smaller machine tool without sacrificing much practical functionality. It’s almost software-like in it’s focus on a singular purpose. Why reinvent what the table saw can do when the user probably already has access to a table saw that will cut stock better? MatchSticks is an entire machine bent around one goal, making the hard stuff easier.

It’s worth noting that MatchSticks was designed as an exploration into computer/human interaction for the ACM Conference on Human Factors in Computing Systems so it’s not a commercial product quite yet (we’re eagerly waiting!). For a much more in depth look at the project and its goals and learnings the full research paper is available here. Their intro video is down after the break.

Thanks [ethan] for the tip!

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Literary Camouflage For Your Router

June 27, 2018 by Brian McEvoy 39 Comments

What is suspicious about the books in the image above? Is it that there is no bookend? How about the radio waves pouring out of them? [Clay Weiland] does not like the way a bare router looks in the living room, but he appreciates the coverage gained by putting it in the middle of his house. He added a layer of home decorating camouflage in the form of some second-hand book covers to hide the unsightly bit of tech.

There isn’t a blog post or video about this particular build anywhere. The photos were submitted to our tip line as-is with the note that a table-saw is involved. We can safely infer that book covers are stripped of their pages and filled with wooden blanks painted white and stuck together to look like a cluster of literature. The takeaway from this example is that our tech does not have to be hidden away like a secret, or disrupt the decor, it can be placed as functionally as possible without sacrificing Feng Shui.

If hiding behind books piques your interest, try a full-fledged version, or this smooth operator.

Thank you, [George Graves], for encouraging people to use our tip line.

Cheap Stuff To Hack: A Router With An SDR For $13

May 30, 2018 by Brian Benchoff 41 Comments

The history of consumer electronics is littered with devices that are relatively uninteresting at first, but become spectacular platforms for hardware exploitation once a few select people figure out how everything ticks. The Linksys WRT54G was just a router until someone figured out how to put a complete Linux system on them. Those RTL-SDR dongles were just for capturing over the air TV until someone realized they were actually a software-defined radio. The CueCat was just dot-com boom marketing garbage until… well, we picked up a lot of CueCats regardless.

Now there’s a new device sitting on the shelves at Walmart just waiting for some Linux hackers to have a go. It’s the Tzumi MagicTV, a device that allows you to watch over-the-air television on your phone. What’s inside? It’s a WiFi router, an RTL-SDR, and a battery pack in one tiny package. The best part? It costs $13, and apparently Walmart is just blowing them out.

Right now, there aren’t too many details on what’s going on inside the Tzumi MagicTV box, however, the discussion over on the RTLSDR subreddit has revealed enough to give us a good idea of what’s going on. The router inside the MagicTV is a TP-Link TL-WR703N, the exact same WiFi router that took the WRT54G’s place as the king of hackable routers a few years ago. The SDR chip is the same as the Astrometa DVB-T2, one of the common TV tuners on-a-stick. Other than that, there are TX and RX pins on the board, SSH is open, no one knows the password, but as of this writing, a few people are putting John the Ripper to work trying to break into this box.

What is the end goal of cracking this Linux box wide open? Well, it’s a WiFi router and an SDR, so if you want to make your own Flightaware ADS-B logger, that could be on the table. Of course, you could actually use it for its intended purpose and pull down over-the-air TV to your local network, but that seems so pedestrian after getting root on a $13 box from Walmart.

Thanks [Adam] for the tip!

Building The Perfect Home Router

April 12, 2018 by Tom Nardi 43 Comments

When a favorite piece of hardware dies, it’s fairly common to experience a bit of dread. The thought that now you’ll have to go through the process of getting a replacement for the device can be very troubling, and is fraught with difficult questions. Is the hardware still available? Has it been made obsolete by something else in the time you’ve had it? But while it can be a hassle, there’s no question you can come out the other side better than you went in. Sometimes it takes the passing of an old piece of gear for you to really embrace what’s possible with the latest and greatest.

That’s exactly what happened to [Tyler Langlois]. When his trusty home router finally gave up the ghost, he was left with a couple of options. He could get another consumer router, upgrade to a enterprise-level model, or take the road less traveled and build his own router to his exacting specifications. Since you’re reading about it on Hackday, we’ll give you one guess as to which door he went through.

The blog post [Tyler] has written up about the saga of building his own router is an incredible resource for anyone who might be thinking of taking the plunge into DIY networking. From selecting the proper hardware to the nuances of getting all of the software packages installed, this is an absolute treasure trove. At the beginning of the post he mentions that the post shouldn’t be considered a comprehensive guide, but considering we’ve seen commercial hardware that wasn’t documented this well, we’d have to respectfully disagree on that point.

Some elements of his homespun may come as something of a surprise. For one, [Tyler] bucked the hive mentality and determined the Raspberry Pi simply wasn’t up to the task due (at least in part) to the single 100 Mbps network interface. He ended up going with an ESPRESSObin, a relatively niche Linux SBC that features an onboard gigabit switch in addition to a fairly hefty spec sheet. He also decided to forgo WiFi entirely, and leave the intricacies of wireless networking to a standalone access point from Ubiquity.

A router is often overlooked as just another piece of consumer kit sitting around the house, but it’s actually an excellent place to flex your creative and technical muscle. From adding a remote display to converting it into a mobile battle tank, there’s a lot more you can do with your router than stare at the blinkenlights.

The Tachometer Inside Your Smartphone

February 8, 2018 by Dan Maloney 26 Comments

It’s the latest in instrumentation for the well-appointed shop — an acoustically coupled fast Fourier transform tachometer. Sounds expensive, but it’s really just using a smartphone spectrum analyzer app to indirectly measure tool speeds. And it looks like it could be incredibly handy.

Normally, non-contact tachometers are optically coupled, using photoreceptors to measure light flashing off of a shaft or a tool. But that requires a clear view of the machine, often putting hands far too close to the danger zone. [Matthias Wandel]’s method doesn’t require line of sight because it relies on a cheap spectrum analyzer app to listen to a machine’s sound. The software displays peaks at various frequencies, and with a little analysis and some simple math, the shaft speed of the machine can be determined. [Matthias] explains how to exclude harmonics, where to find power line hum, isolating commutator artifacts, and how to do all the calculations. You’ll need to know a little about your tooling to get the right RPM, and obviously you’ll be limited by the audio frequency response of your phone or tablet. But we think this is a great tip.

[Matthias] is no stranger to shop innovations and putting technology to work in simple but elegant ways. We wonder if spectrum analysis could be used to find harmonics and help with his vibration damping solution for a contractor table saw.

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Router Rebooter Eliminates Hassles

January 31, 2018 by Bryan Cockfield 85 Comments

Some low-end or older routers might get you a decent WiFi network in your house or apartment, but often these cheaply made devices are plagued with subtle software problems that cause the router itself to become unresponsive after a few days of operating. One solution is to just power cycle the router by hand whenever the Internet disappears, but a better solution is to build something that does that for you.

[Charlie] had this problem as the de facto IT person in his family, and didn’t want to keep getting bothered for such a simple problem. His solution involves a relay, an ESP8266, and a Wemos D1 mini. The device connects to the Internet through the router and occasionally sends out pings to another address. If it can’t ping the address successfully after a certain time period, the device power cycles the router by activating the relay.

Since this isn’t the newest idea out there, there are many ways to solve this problem if you are constantly annoyed by router issues, whether from your own router or from friends and family who treat you as their personal IT department. One solution doesn’t involve any extra hardware at all as long as you have a computer near your router/modem already, and others solve this problem when it happens to the modem rather than the router.

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Optical Tach Addresses The Need For Spindle Speed Control

January 28, 2018 by Dan Maloney 8 Comments

With CNC machines, getting the best results depends on knowing how fast your tool is moving relative to the workpiece. But entry-level CNC routers don’t often include a spindle tachometer, forcing the operator to basically guess at the speed. This DIY optical spindle tach aims to fix that, and has a few nice construction tips to boot.

The CNC router in question is the popular Sienci, and the 3D-printed brackets for the photodiode and LED are somewhat specific for that machine. But [tmbarbour] has included STL files in his exhaustively detailed write-up, so modifying them to fit another machine should be easy. The sensor hangs down just far enough to watch a reflector on one of the flats of the collet nut; we’d worry about the reflector surviving tool changes, but it’s just a piece of shiny tape that’s easily replaced. The sensor feeds into a DIO pin on a Nano, and a small OLED display shows a digital readout along with an analog gauge. The display update speed is decent — not too laggy. Impressive build overall, and we like the idea of using a piece of PLA filament as a rivet to hold the diodes into the sensor arm.