The carbon fiber look is a pretty hot design element for things these days. Even things that have no need for the strength and flexibility of carbon fiber, from phone cases to motorcycle fenders, are sporting that beautiful glossy black texture. Some of it only looks like the real stuff, though, so it’s refreshing to see actual carbon fiber used in a project, like this custom headphone rack.
True, this is one of those uses of carbon fiber that doesn’t really need it – it just looks cool. But more importantly, [quada03]’s build log takes us through the whole process, from design to mold construction to laying up the fiber mats and finishing, and shows us how specialized equipment is not needed to achieve a great result. A homemade CNC router carves the two-piece mold out of Styrofoam, which is then glued up and smoothed over with automotive body filler. The epoxy-soaked carbon fiber mats are layered into the mold with careful attention paid to the orientation of the fibers, and the mold goes into one of those clothes-packing vacuum bags for 24 hours of curing. A little trimming and sanding later and the finished bracket looks pretty snazzy.
We’ve discussed the basics of carbon fiber fabrication before, but what we like about [quada03]’s build is that it shows how approachable carbon fiber builds can be. Once you hone your skills, maybe you’ll be ready to tackle a carbon fiber violin.
Filed under: misc hacks
[Gregg Eshelman] reproduces plastic parts for antique car restorations for a living; likewise, he’s very good at it. Greg always chimes in with helpful hints whenever we post about resin casting. Shown above is a lens for a car turn signal. Manufactured in 1941, having [Gregg] cast a few copies is an easy option for replacing the rare part.
[Gregg] uses a similar method to us, but it is easy to see that he has done it more and his process has been refined by lots of experience. We really liked how he avoids using expensive foam core by wrapping cardboard in packing tape, or using the kind that has a plastic coating on it; the kind most retail packaging is made out of. He also has better techniques for keying the part to be manufactured, and prepping difficult geometry between different mold halves. It also never would have occurred to us to use Dremel cutting disks to cut the sprues and air vents in the silicone, a surprisingly tricky material to cut precisely with a knife.
It’s always nice when a professional takes time to write about their processes for the hobbyist trying to emulate it. We hope [Gregg] writes more tutorials, and continues to contribute in the comment section. If you have your own fabrication techniques to share we’d love to hear about it on the tips line.
Filed under: how-to
Just over a year ago, Particle (formerly Spark), makers of the very popular Spark Core and Particle Photon WiFi development kits, released the first juicy tidbits for a very interesting piece of hardware. It was the Spark Electron, a cheap, all-in-one cellular development kit with an even more interesting data plan. Particle would offer their own cellular service, allowing their tiny board to send or receive 1 Megabyte for .00 a month, without any contracts.
Thousands of people found this an interesting proposition and the Electron crowdfunding campaign took off like a rocket. Now, after a year of development and manufacturing, these tiny cellular boards are finally shipping out to backers and today the Electron officially launches.
Particle was kind enough to provide Hackaday with an Electron kit for a review. The short version of this review is the Electron is a great development platform, but Particle pulled off a small revolution in cellular communications and the Internet of Things
The Current State of Machine to Machine Cellular
Small microcontroller dev boards are nothing new. The technology to turn a hat, belt buckle, or bicycle into something that receives data from a cellphone tower has been around for more than a decade now, and a few very old blogs and forums preserved on archive.org reflect this fact. An old Siemens, Nokia, or Motorola phone, with the right serial cable,could be a microcontroller’s connection to the outside world.
More recently, Sparkfun and Adafruit have been putting together their own cellular modules for Arduinos and other similar boards. These modules, like SparkFun’s Cellular Shield, Adafruit’s FONA, and Seeed’s RePhone all provide easy-to-use cellular modules that plug into an Arduino. The problem is phone companies historically didn’t want to deal with a bunch of Arduinos blinking LEDs through their network.
While one would think more devices on a cellular network would be a good thing for a carrier, this is not what [Zach Supalla], CEO of Particle, found when creating the Electron. The success of a carrier in the eyes of shareholders depends on ARPU, average revenue per user, or the total revenue divided by the number of subscribers.
While the ARPU is great when AT&T, Sprint, and Verizon are selling multi-Gigabyte plans to smartphone users, it’s a terrible measure if a company is selling a lot of cheap one Megabyte plans. The economics of cellular carriers is why we don’t have a cellular Internet of Things; it doesn’t make sense for the carriers to do it.
Instead of going through the usual cellular carriers, Electron users will be getting their service directly through Particle. It’s a setup called a Mobile Virtual Network Operator, or MVNO, that allows carriers to work through Particle to provide plans without much data but at a very low price.
It’s a setup that works well for a cellular device that’s the size of a stick of gum. If you walk into your old Radio Shack, you will get blank stares (again!) if you ask about a low-cost plans that provide just a few Megabytes of data. Setting up a SIM card with Particle is as simple as entering a few digits into a webpage, entering your credit card info, and enjoying a Megabyte per month of data on a tiny microcontroller board.
The Hardware and Development Toolkit
Particle already has a few hardware products under their belt, such as the Particle Photon and Core, a very popular ARM and WiFi development board. It’s incredibly useful for people who don’t want to futz around with bare ESP8266 modules. To anyone who has ever used a Photon or Core, the Electron will quickly become very familiar.
Tucked away on the bottom of the Electron is the STM32F205 microcontroller, presenting 36 total pins to the outside world. The functions presented on these pins include UART, SPI, I2C, and CAN bus. In total, there are 12 ADC channels, 3 UARTs, 2 SPIs, 1 I2C, 2 CAN, 2 DACs, and 13 PWM channels. 1 MB of Flash is included, and 128k of RAM is available. It’s an extremely capable board if you compare it to the Arduinos of a few years ago, and can go toe to toe with slightly more modern boards such as the Teensy 3.2.
The entire hardware design for the Electron is open source. Incidentally, Particle used Eagle to design the board.
As for development for the Electron, choices abound. The easiest by far is a web-based Arduino-like development environment, Particle Build. Just like the Arduino IDE, Build will give you just enough to write some code and flash it to your device. Libraries for GPS modules, LCDs, switches, temperature sensors, and everything else that would normally be used in a one-off Internet connected project abound. While it’s not a full-blown IDE, it’s good enough and allows for over the air flashing of the Electron.
Particle’s Tinker app, a smartphone-based development environment is also available for the Electron. This app will allow you to read and write individual pins in a strange, ‘you know what’s cool? Visual programming’ way.
There are more than a few people who believe that a web-based IDE, especially one hosted on a server you don’t own, is a terrible idea. Lucky for us, Particle has made all their development tools open source, allowing anyone to roll their own personal cloud. For anyone concerned about the usefulness of Particle’s boards five or ten years down the line, this is a necessary feature.
Click to view slideshow.
The Future of the Electron and Particle Cellular
More than any other Internet of Things company, Particle is seeing a lot of their modules become the basis of real products. There’s a reason for this: they’re one of the few hardware developers that are sinking money into certifications. If you wanted to build a device with a Particle Photon inside it, the certifications are already taken care of. The FCC and cellular certifications for the Electron module are in the works, but [Zach] says that will happen.
Of course, any developer building a piece of hardware with Particle boards probably isn’t using a stock Photon or Electron. There’s no need for USB ports or pin headers when a board is stuffed inside a black box, anyway. For the smarts that go into a product, Particle already has a WiFi module, the P0 and P1, and [Zach Supalla] says Particle is considering a cellular module that would also be FCC and CE certified.
The Electron is a great piece of hardware, but it’s not the biggest development in the world of cellular-enabled hardware. That would be Particle’s MVNO and the no-contract, one Megabyte cellular plan that costs only a few bucks a month. The burning question on everyone’s mind is, ‘will Particle sell SIMs to people who want to roll their own hardware?’. The answer to this, at least for now, is yes. Even if you’re not interested in the Electron itself, the cheap cellular plan is undeniably interesting. It’s cheaper than other MVNOs like Ting, is designed to be a purely machine to machine plan, and it will be coming soon.
The Requisite 2G Warning
Particle is offering three version of the Electron. Two are for 3G networks – the U260-based board is for North America, the U270 is for Europe. The third version of the Electron is for 2G networks. The 2G version is cheaper, but this may be a false economy. In the US, AT&T will begin shutting down 2G networks “soon” – either starting January 1, 2017, or whenever it doesn’t make economic sense to keep the 2G networks running.
Particle already has a lot of experience building Internet of Things things. The Core and Photon are excellent WiFi development boards with a strong development platform and a very capable cloud backend. The Electron is the continuation of this, expanding the Internet of Things to devices that move more than a few hundred meters when being used, or operate where WiFi networks aren’t available.
While the hardware is good, the big story here is Particle becoming a cellular network. Smartphones, as we know them today, have been around for nearly a decade and until now, no one – at least at a large carrier – has realized the value of giving a few kilobytes of data a month to tiny battery-powered devices. Somehow or another, Particle solved this problem, and they’re not locking it down to only their devices.
Particle will be shipping rewards out to Kickstarter backers beginning today, and the Electron (and SIM) will be available on the Particle website in due time.
Filed under: Microcontrollers, news, reviews
Resin casting lets you produce parts that would be otherwise impossible to make without a full CNC and injection molding set-up. It costs about as much as a 3d printer, 300 to 600 US dollars, to get a good set-up going. This is for raw material, resin, dye, pressure chamber, and an optional vacuum degassing set-up. A good resin casting set-up will let you produce parts which are stronger than injection molding, and with phenomenal accuracy, temperature resistance, and strength. I will be covering various techniques from the simple to advanced for using resin casting from a hacker’s perspective.
Today I will be replicating a part exactly. I searched my house for a pending project. I wish I had a more exciting part to duplicate, like a broken hinge or plastic case that I’d like in a different color, but I lost a button on my favorite coat. So I’ll be making a matching set of buttons.
You’ll need a basic resin casting set-up. For the raw materials, I duplicated the suggestions from the Guerrilla Guide — the standard handbook for fabricating things in your own workshop. So far this has worked out great. I’ve also had a lot of fun casting urethane rubber for wheels and flexible parts, but that’s for another chapter.
I do recommend deviating from the Guerrilla Guide in one regard though. Absolutely skip the purchase of a vacuum degassing chamber if you are on a budget. Buy a pressure casting set-up. As long as you cure both your molds and your resin under pressure you won’t have many issues. The most bang for your buck will be a cheap pressure casting chamber made from a paint pot and a discount compressor. I waited for a 20% off sale at my local import store and got my set up for about 150 US Dollars, pot, pnuematics, compressor, and all.
There are a few other accessories I’ve found to be very handy. One is a miniature paint mixer; most of my resin casting is done at small scale. The silicone doesn’t care as much but the resin demands that it be mixed very very well or it will cure improperly (usually with strange and baffling material properties, like being weirdly rubbery, or super brittle and sticky at the same time). I also recommend a box of nitrile gloves, the good kind surgeons might use. Most of these chemicals won’t harm you today, but you may build up an allergy to them from constant exposure, which would be hideously inconvenient tomorrow. Also, a trustworthy electronic precision scale. I bought a used Made In USA +-0.01g scale for 25 US Dollars of eBay. It improved my results dramatically. I also recommend the purchase of a brick of soft Plasticine. This is a modeling clay that is oil based and never dries out. Make sure you get one that specifically mentions being sulfur free or it will interfere with your silicone. You can use the clay to do all sorts of magic to plastic parts. It’s also reusable. Lastly, some lead weights or shot bags and a ton of rubber bands; these are used to hold your molds together.
Preparing the Part You Want to Duplicate
Once you have your set-up together, the process is relatively straight forward. First remove the plastic part from its assembly and clean it thoroughly. The silicone will pick up amazingly small defects. You’ll replicate finger prints and dust. It’s pretty spectacular. You may also want to take this time to spray the plastic with a mold release. You’ll want to let the release dry and polish it off. It’s usually optional, as silicone doesn’t stick well to many thermoplastics, but if you have a questionable textured surface, you might as well. It may cause some detail loss.
Most duplicated parts will need a two part mold. You’ll hold the parts in position and cast one half of the mold, then, leaving the parts in the silicone, you’ll cast the mating silicone mold on top. There are two methods I employed. My usual is to use light glues like rubber cement, or blue tack to hold the part onto a flat surface, and then build the keys and sprues using modeling clay on this flat surface. I usually get a better seal between the mold halves this way.
Unfortunately, I generated a fail of the week; so for this tutorial, I’ll go with the other method, which is to embed the parts in a base of modeling clay. I find that this method is exceptionally hard for a non-sculptor to work into a flat surface, and the clay gets everywhere. It works well, though so don’t be deterred from this. I would even say it is the better method of the two. Don’t get the hard modeling clay if you want a good time of it though.
Making a Mold of the Part
So, first take some foam core and lay your parts out on it. Think about the orientation of the pour. You will be displacing air and replacing it with bubbles. You want clear path for the air to leave and the resin to enter. There will also be some flashing after the pour is complete. The better you make your mold, the less flashing there will be. In this case I did a shameful job, so there was a bunch of clean-up work to do before my part was done. I decided that the edges of the buttons would be the most easily repaired of defects so I picked that as the parting line for my two part mold.
I then layered the bottom of my mold with Plasticine clay. My clay is terribly hard, so I put it in a plastic bag in a hot water bath to soften. I pressed the buttons boring side down into the mold. I want to get the most difficult side captured in the silicone first. Then I took my index finger and pressed some indexing holes into the clay. This will help me line up the mold later. I would recommend using something more precise, like a pen cap, but it was what was on hand at the time. Lastly, I took a toothpick and carefully sculpted the clay to make a nice even line around every button. I also cleared the button holes, as it is a good idea to have difficult geometry captured on one side of the mold only.
Next comes the fun part. Pouring the first half of the mold. For this I estimated that about 190 grams would be enough. I used a very sophisticated equation to come up with this figure; my scale can only weigh up to 200 grams, and this looked like a lot. Carefully weigh out the two components of the silicone. Again, very very puzzling things happen when you don’t. Next, stir forever. You have a while before the silicone begins to set, so stir. Stir until your arms burn. You can’t over do it. You should end up with a very uniformly colored, bubble filled, slime. If you have a vacuum degassing chamber, now is the time to do that. Next comes pouring time.
If you are going to pressure cast the resin you absolutely must pressure cast the mold at the same pressure you will cast the resin. This way any air trapped in the mold will compress to the right dimension under casting pressure. For a detailed mold, take a brush and gently brush silicone onto the most detailed surfaces. Then, take the silicone and hold it as high above the positive as you can, and start pouring a thin stream into the mold. This breaks most of the larger bubbles and trades them for smaller bubbles that won’t matter as much to the pressure casting process. Pour until you fill the mold and then place the mold as level as you can into the pressure chamber.
Depending on your silicone, now comes the wait. Mine takes about 12 hours to cure. Once the period is over, take the mold out of the chamber and remove it from the foam core. Flip it over and carefully remove the clay. Ideally you can do so without disturbing the item you would like to duplicate. Now, you can either go ahead and cast the next half of the mold and carve the sprues into the mold after, or you can make the sprues now with modeling clay. Both have their advantages and disadvantages. For this one I decided to make the sprues out of modeling clay.
Note how the sprues are placed so that air can flow up and out of the mold without leaving behind bubbles. I took a razor and pressed against the edge of the sprues to minimize the contact area with the part.
Once the mold has cured, it comes time to see if all our work paid off. First separate the mold halves by simply cutting a quarter inch (6mm) off the edge of the mold all around. Then carefully peel apart the two halves. Once you have them separated remove all the originals and clay. If you decided not to make clay sprues, this is the point where you carve in sprues using a knife of chisel.
Fit the halves of the mold back together and sandwich them between something inflexible. Wrap the whole assembly with rubber bands.
Finally, Time to Cast the Part!
Set out all your equipment. The scale being the most important. Weigh out the positives to get a good estimate of how much resin you’ll need to fill the mold. Then add a decent amount to that number, in this case I just doubled it, for short runs it’s better to waste than to redo.
Put a plastic cup on the scale and zero it. Add a few drops of colorant to the cup. For something this size, just dipping the end of the mixer into the pigment jar pulled out enough to dye all the parts. Tare it again. Pour in A and B part in the ratio described by your resin. Then mix forever. Again, the more you mix the better your result.
Pour the resin into the mold until it fills up, then tap the sides. The level of the resin should go down. Tap and fill until you can’t anymore. Then put the whole assembly into the pressure chamber and pressure cast again. Now we wait.
Once we have reached the demolding time for the resin (this is usually found in the datasheet) it is safe to demold. Take all the rubber bands off and separate the mold.Since I used entirely too many rubber bands and planks of foamcore I had some serious flashing issues. These broke off easily though, but I had to spend some more time polishing the edges.
Once the parts were finished I sewed the buttons back onto the coat. I’m not the best at tailoring, so I’m certain I’ll lose another button, but that’s okay because I have three extra waiting for that day! Even if I lose them all I still have a mold. I could even cast them in a different color if I’d like to look like a concierge. Pretty cool!
Filed under: Hackaday Columns, how-to
When [turingbirds] was looking around for the absolute minimum connector for a JTAG adapter, he wanted something small, that didn’t require expensive adapters, and that could easily and reliably connect a few JTAG pins to a programmer. This, unsurprisingly, is a problem that’s been solved many times over, but that doesn’t mean there isn’t room for improvement. [turingbirds] found his better solution by looking at some old card edge connectors.
Instead of 0.1″ pitch pin headers, weirder and more expensive connectors, the Tag Connect, or even pogo pins, [turingbirds] came up with a JTAG adapter that required no additional parts, had a small footprint, and could be constructed out of trash usually found behind any busy hackerspace or garage. The connector is based on the venerable PCI connector, chopped up with a Dremel and soldered to a JTAG or ISP programmer.
This is simply a card edge connector, something the younglings seem to have forgotten. Back in the day, card edge connectors were a great way to connect peripherals, ports, and anything else to the outside world. They were keyed, and you could only put them in one way. They were relatively cheap, and with a big coil of ribbon cable, you could make custom adapters easily. For low-speed connections that will only be used a few times, it’s very hard to beat a card edge connector.
Of course the connector itself is only half of the actual build. To turn a chopped up PCI connector into a JTAG adapter, [turingbirds] made footprint and part files for his favorite PCB design tool. In this case it’s Eagle, and the libraries that will plop one of these connectors down are available on GitHub.
Is this the latest and greatest way to plug a programmer into a board? No, because this has been around for 30 or 40 years. It does, however, put a programming port on a PCB with zero dollars in components, a minimum of board footprint, and uses parts that can be salvaged from any pile of old computers.
Filed under: tool hacks
Inspired by TRON, [lasttraveler] decided to try his hand at building a Balance Board — basically a giant joystick pad you can stand on to control.
Constructed of solid wood, the switches are actually very simple — he’s just using tin foil to make the contacts. By opening up the sacrificial keyboard, he’s taken the up/down/left/right keys and wired the contacts directly to the four tin foil pads. A recess in the bottom of the board allows the rest of the keyboard to remain intact — in case he ever wants to take it apart again. Or add new buttons!
Wooden crossbeams in the shape of an X allow the board to balance in the middle without touching any of the contacts — but as soon as you lean the connections are made and you’re off to the races!
Now strap on a VR headset and play some TRON! Though if you want even more accurate control you might want to pick up a cheap Wii balance board instead.
Filed under: computer hacks, peripherals hacks
In the 1970s and 1980s, a lot of us learned to program using good old-fashioned BASIC on machines ranging from Altairs, Commodores, Apple IIs, and the like. Sometime in the 80’s the IBM PC running MSDOS because the de facto standard, but it was still easy enough to launch BASIC and write a simple little program. Of course, there were other programs, some serious like C compilers, some semi-serious like flight simulators, and some pure fun like Wolfenstein 3D.
If you read Hackaday, you’ve probably noticed that a lot of people emulate old computers–including old MSDOS PCs–using a variety of techniques, including Raspberry PI boards running DOSBox or another emulator. Honestly, though, that’s a lot of effort just to run some old software, right? You can load up DOS emulators on your desktop too. That’s a little easier, but you still have to find software. But if you are as lazy as we are, you might want to check out the MSDOS collection at archive.org.
The collection has over 7,000 old MSDOS titles which is impressive. But what is fascinating is that they will all run inside your Web browser. You are two clicks away from running BASIC, Borland C, flight simulators, or even Commander Keen. Be careful, though. Some key strokes (like Control+C) may not work in the browser.
If you are really hardcore, you can even boot some old versions of Windows in your browser. Or, if you want to go further back in time, try emulating DOS in your browser and then emulating a TRS-80 under DOS. There’s even old versions of Microsoft Word and Wordperfect if you want to write blog posts old school.
If you wish to do some hardware hacking, you don’t have to do all this in the browser. There are also plenty of old computers you can emulate in your browser. There’s even a Windows 95 in a browser (see the video below).
Filed under: misc hacks
Apple’s rumored “iPhone 5se” may come in Silver, Space Gray and a shade of pink that is different than the ROse Gold of the iPhone 6s.
iPhone Hacks | #1 iPhone, iPad, iOS Blog
Kids these days, they have it so easy. Back in the old days, we learned our elements the hard way, by listening to “The Elements” by Tom Lehrer over and over until the vinyl wore out on the LP. Now, thanks to [Karyn], kids can learn the elements by playing “Battleship” – no tongue-twisting lyrics required.
For anyone familiar with the classic “Battleship” game, you’ll wonder why no one thought of this before. [Karyn]’s version of the game is decidedly low-tech, but gets the job done. She printed out four copies of the periodic table, added letters to label the rows, and laminated them. A pair of tables goes into a manila file folder, the tops get clipped together, and dry-erase markers are used to mark out blocks of two to five elements to represent the ships of the Elemental Navy on the lower table. Guesses at the location of the enemy ships can be made by row and series labels for the elementally challenged, or better yet by element name. Hits and misses are marked with Xs and Os on the upper table, and play proceeds until that carrier hiding in the Actinide Archipelago is finally destroyed.
This is pure genius in its simplicity and practicality, but of course there’s room for improvement. The action-packed video after the break reveals some structural problems with the file folders, so that’s an obvious version 2.0 upgrade. And you can easily see how this could be used for other tabular material – Multiplication Table Battleship? Sounds good to us. And if your nippers catch the chemistry bug from this, be sure to take a deeper dive into the structure of the periodic table with them.
Now, if you’ll excuse me: “There’s antimony, arsenic, aluminum, selenium, and hydrogen and oxygen and nitrogen and rhenium….”
[Via the Adafruit blog]
Filed under: chemistry hacks, misc hacks