A CNC Plasma Cutter Table, From The Shop Floor Up

June 20, 2018 by Dan Maloney 2 Comments

Some projects are simple, some focus on precision and craftsmanship, and some are more of the quick-and-dirty variety. This home-built CNC plasma cutter table seems to follow a “go big or go home” philosophy, and we have to say we’re mighty impressed by the finished product.

For those who follow [Bob]’s “Making Stuff” YouTube channel, this build has been a long time coming. The playlist below has eight videos that cover the entire process from cutting the first tubes of the welded frame to the initial test cuts with the finished machine. [Bob] took great pains to make the frame as square and flat as possible, to the extent of shimming a cross member to correct a 0.030″ misalignment before welding. He used good-quality linear rails for each axis, and hefty NEMA 23 steppers. There were a few false starts, like the water pan that was going to be welded out of five separate pieces of steel until the metal shop guys saved the day with their press brake. In the end, the machine turned out great; with a build cost of $2000 including the plasma cutter it’s not exactly cheap, but it’s quite a bargain compared to similar sized commercial machines.

We think the video series is a great guide for anyone looking to make a CNC plasma table. We’ve seen builds like this before, including [This Old Tony]’s CNC router. Watching these builds gives us the itch to get into the shop and start cutting metal. Continue reading “A CNC Plasma Cutter Table, From The Shop Floor Up” →

Hexabitz, Modular Electronics Made Easier

June 20, 2018 by Jenny List 14 Comments

Over the years there have been a variety of modular electronic systems allowing the creation of complex circuits by the interconnection of modules containing individual functions. Hexabitz, a selection of interlocking polygonal small PCBs, is just such a system. What can it bring to the table that others haven’t done already?

The problem facing designers of modular electronics is this: all devices have different requirements and interfaces. To allow connection between modules that preserves all these connections requires an ever-increasing complexity in the inter-module connectors, or the application of a little intelligence to the problem. The Hexabitz designers have opted for the latter angle, equipping each module with an STM32 microcontroller that allows it to identify both itself and its function, and to establish a mesh network with other modules in the same connected project. This also gives the system the ability to farm off computing tasks to individual modules rather than relying solely upon a single microcontroller or single-board computer.

An extremely comprehensive array of modules can be had for the system, which lends it some interesting possibilities, however, it suffers from the inherent problem of modular electronic systems, that it is less easy to incorporate non-standard functions. If they can crack a prototyping module coupled with an easy way to tell its microcontroller to identify whatever function is upon it, they might have a winner.

Analog Discovery 2 As A Vector Network Analyzer

June 20, 2018 by Al Williams 7 Comments

A while back, I posted a review of the Analog Discovery 2, which is one of those USB “do everything” instruments. You might recall I generally liked it, although I wasn’t crazy about the price and the fact that the BNC connectors were an extra item. However, in that same post, I mentioned I’d look at the device’s capabilities as a network analyzer (NA) sometime in the future. The future, as they say, is now.

What’s an NA?

In its simplest form, there’s not much to an NA. You sweep a frequency generator across some range of frequencies. You feed that into some component or network of components and then you measure the power you get out compared to the power you put in. Fancy instruments can do some other measurements, but that’s really the heart of it.

The output is usually in two parts. You see a scope-like graph that has the frequency as the X-axis and some sort of magnitude as the Y-axis. Often the magnitude will be the ratio of the output power to the input power as a decibel. In addition, another scope-like output will show the phase shift through the network (Y-axis) vs frequency (X-axis). The Discovery 2 has these outputs and you can add custom displays, too.

Why do you care? An NA can help you understand tuned circuits, antennas, or anything else that has a frequency response, even an active filter or the feedback network of an oscillator. Could you do the same measurements manually? Of course you could. But taking hundreds of measurements per octave would be tedious and error-prone.

Continue reading “Analog Discovery 2 As A Vector Network Analyzer” →

Friday Hack Chat: Ladyada On Creative And Interactive Robotics

June 20, 2018 by Brian Benchoff 7 Comments

Somewhere at the intersection of microcontrollers, open source toolchains, the Maker Movement, and the march of technology, there’s a fuzzy concept that can best be described as robotics or physical computing. Instead of a computer in a box or a dumb microcontroller, these projects interact with the outside world. Whether that’s through the Internet, tapping a bunch of sensors, or just waving the arm of a servo around, there’s a need for a platform that actually does all of this stuff. For this week’s Hack Chat, we’re going to be talking all about creative and interactive robots, and you’re invited.

Our guest for this week’s Hack Chat will be Limor “Ladyada” Fried, the founder of Adafruit, and someone who needs no introduction but we’re going to do it anyway. Adafruit began as a weird side project selling exact reproductions of the Roland TB-303, building cell phone jammers, and making guides to build your own USB power bank before USB power banks were a thing. This has grown into Adafruit, a company with over 100 employees in the heart of New York City, one of the best places for learning and making electronics, and a place that does everything Open Source with zero loans or VC money. By any objective measure, Adafruit has become the most successful business story to come out of the Maker Movement, however nebulously that can be defined.

This week the Hack Chat will be focused on the CRICKIT, the Creative Robotics and Interactive Construction Kit. The CRICKIT is an add-on to Adafruit’s Circuit Playground that allows you to build your own robot with CircuitPython, MakeCode, or just Arduino. There’s support for arts, crafts, sensors, audio, animatronics, physical computing, kinetic sculptures, science experiments, and just about anything else you can think of. Need an example? Here’s Blue Öyster Cult. Here’s that robot that came with the NES. It’s all great fun.

You are, of course, encouraged to add your own questions to the discussion. You can do that by leaving a comment on the Hack Chat Event Page and we’ll put that in the queue for the Hack Chat discussion.

Our Hack Chats are live community events on the Hackaday.io Hack Chat group messaging. This week is just like any other, and we’ll be gathering ’round our video terminals at noon, Pacific, on Friday, June 22nd. Here’s a clock counting down the time until the Hack Chat starts.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io.

You don’t have to wait until Friday; join whenever you want and you can see what the community is talking about.

Print Physical Buttons For Your Touch Screen

June 20, 2018 by Brian McEvoy 5 Comments

Modern handheld gaming hardware is great. The units are ergonomic powerhouses, yet many of us do all our portable gaming on a painfully rectangular smartphone. Their primary method of interaction is the index finger or thumbs, not a D-pad and buttons. Shoulder triggers have only existed on a few phones. Bluetooth gaming pads are affordable but they are either bulky or you have to find another way to hold your phone. Detachable shoulder buttons are a perfect compromise since they can fit in a coin purse and they’re cheap because you can make your own.

[ASCAS] explains how his levers work to translate a physical lever press into a capacitive touch response. The basic premise is that the contact point is always touching the screen, but until you pull the lever, which is covered in aluminum tape, the screen won’t sense anything there. It’s pretty clever, and the whole kit can be built with consumables usually stocked in hardware stores and hacker basements and it should work on any capacitive touch screen.

Physical buttons and phones don’t have to be estranged and full-fledged keyswitches aren’t exempt. Or maybe many capacitive touch switches are your forte.

Continue reading “Print Physical Buttons For Your Touch Screen” →

Teardown: Box Of Pain (Gom Jabbar Sold Separately)

June 20, 2018 by Tom Nardi 34 Comments

I immediately felt uncomfortable when I realized this thing is called the “Breo iPalm520 Acupressure Hand Massager”. You’re supposed to stick your hand into it, and through unknown machinations it performs some kind of pressure massage complete with heating action. It’s like one of those pain boxes from Dune. It’s all the more disturbing when you realize the red button on the thing is an emergency release. That’s right, once your hand is in this contraption you can’t take it out until the thing has had its way with you or you tap out.

At least once a week I try to get to the local thrift store to look for interesting things. I’d like to be more specific than “interesting things”, but truth be told, I never really know what I’m looking for until I see it. Sure there’s the normal consumer electronics kind of stuff, but I’ve also found some very nice laboratory equipment, computer parts, software, technical books, etc. You just have to go regularly and keep an eye out for the occasional needle amongst the hay.

I want you to know, Dear Readers, that I did briefly summon the courage to put my hand into this thing and turn it on. Now I am not what one might call an overly brave man, and perhaps that might explain my personal experience. But when it started to hum and heat up, constricting around my hand to the point I couldn’t move my fingers, I screamed like a child and mashed the emergency button as if I was a pilot trying to eject from a mortally wounded aircraft. As far as Frank Herbert is concerned, I’m no human at all.

In an effort to better understand this torture device, lets open it up and see what lurks beneath that futuristic exterior.

Continue reading “Teardown: Box Of Pain (Gom Jabbar Sold Separately)” →

Bunnie Weighs In On Tariffs

June 20, 2018 by Adam Fabio 150 Comments

[Bunnie] has penned his thoughts on the new 25% tariffs coming to many goods shipped from China to the US. Living and working both in the US and China, [Bunnie] has a unique view of manufacturing and trade between the two countries. The creator of Novena and Chumby, he’s also written the definitive guide on Shenzen electronics.

All the marked items are included in the new tariffs

The new US tariffs come into effect on July 6th. We covered the issue last week, but Bunnie has gone in-depth and really illustrates how these taxes will have a terrible impact on the maker community. Components like LEDs, resistors, capacitors, and PCBs will be taxed at the new higher rate. On the flip side, Tariffs on many finished consumer goods such as cell phone will remain unchanged.

As [Bunnie] illustrates, this hurts small companies buying components. Startups buying subassemblies from China will be hit as well. Educators buying parts kits for their classes also face the tax hike. Who won’t be impacted? Companies building finished goods. If the last screw of your device is installed in China, there is no tax. If it is installed in the USA, then you’ll pay 25% more on your Bill of Materials (BOM). This incentivizes moving assembly offshore.

What will be the end result of all these changes? [Bunnie] takes a note from Brazil’s history with a look at a PC ISA network card. With DIP chips and all through-hole discrete components, it looks like a typical 80’s design. As it turns out the card was made in 1992. Brazil had similar protectionist tariffs on high-tech goods back in the 1980’s. As a result, they lagged behind the rest of the world in technology. [Bunnie] hopes these new tariffs don’t cause the same thing to happen to America.