DIY Vacuum Table Makes Lasering Even Easier

March 19, 2016 by 13 Comments

If you’ve ever tried to laser flexible rolls of material you’ll know it can be really annoying to setup in the laser cutter.

Most of the time we use magnets, but then you have to make sure the magnets are clear of the work path — and then you end up wasting extra material… It’d be amazing to have a vacuum table that just sucks down your work piece to keep it in place! As it turns out, it’s not that hard to make!

After getting frustrated lasering warped material themselves, [Martin Raynsford] and the gang decided to make their very own vacuum table — using a laser cutter of course. Continue reading “DIY Vacuum Table Makes Lasering Even Easier” →

MRRF: Jellybox, A STEM-Oriented Printer

March 19, 2016 by 24 Comments

It’s the first full day of fun here at the Midwest RepRap Festival. This year’s turnout is quite impressive—as I’m writing this, we’re an hour or so in and there are already hundreds of people and a couple of R2D2 units milling about.

The talks will begin in a few hours. This year MRRF has expanded to another building, which should tell you something about the growth of this festival. We are excited to hear [Filip] and [Ladi] give a presentation about Jellybox, a STEM-driven project he started to bring 3D printing into education in a comprehensive and hands-on way. The initial idea was based on [Jean Piaget]’s theory of constructionism. [Piaget] was a clinical psychologist who helped advance the idea that human learning is greatly influenced by connecting a person’s ideas with their experiences.

Building a Jellybox printer is about as easy as it gets, and takes about 4-6 hours depending on your skill level. The laser-cut clear acrylic panels are connected with zip ties that lock around 90° plastic brackets. The back panel even has a etched diagram that shows where all the connectors should go, and the wiring is neat and tidy by design. It’s meant to be easy to tear down so that teachers can use them again and again with middle and high school-aged students. The Jellybox is open-source; both the extruder and the hot end can be swapped out in a flash.

IMade3D offers one- and two-day intensive courses in the DC area that cover building a Jellybox and learning some things about 3D modeling. The kit is included in the price of admission. Jellybox kits will be available in a few weeks, but can be preordered today for $799.

Hacklet 100 – The 2016 Hackaday Prize

March 19, 2016 by 11 Comments

Welcome to the 100th Hacklet! This has been a huge week for Hackaday, as we launched The 2016 Hackaday Prize. We’ve invited you to change the world. Hackers, makers, and engineers have already answered the call, with nearly 200 entered projects! What better way to celebrate our 100th Hacklet than taking a look at a few of these early entrants?

rarmWe start with [Patrick Joyce] and Raimi’s Arm – Bionic Arm for Kids. Raimi was born with an arm which ends just below the elbow. She’s still a kid – and growing, which means she will quickly grow out of any prosthetic. This has placed bionic arms out of her reach. [Patrick] saw a plea from Raimi’s father for help. 3D printed arms for the disabled are a thing, but [Patrick] couldn’t find one which fit the bill for Raimi. So he’s set out to design one himself. This will be an open source project which anyone with the proper tools can replicate. [Patrick] has already created several test rigs, and is well on the way to building an arm for Raimi and others!

latheNext up is [castvee8] who has entered the 2016 Hackaday Prize with Building Simplified Machinery. Over the years, [Castvee8] has built a few 3D printers and CNC machines. These projects always start with buying the same parts over and over: ground rods, linear bearings, stepper motors, drivers, etc. [Castvee8] is trying to build 3D printed machines which use as few of these vitamins as possible, yet are still strong enough to work in wood, plastic, wax, foam, and other light maker-friendly materials. So far the simple, modular components and electronics have led to a mini mill, mini lathe, and a drill press for things like printed circuit boards. Keeping things low-cost will make these tools accessible to everyone.

turpump[Keegan Reilly] entered Everyman’s turbomolecular pump. Vacuum pumps are great, but everyone knows the real fun starts around 10^-7 Torr. Pulling things down this low requires a specialized pump. Two common designs are oil diffusion pumps and Turbomolecular pumps. Oil diffusion is cheap, but not everyone wants a hot vat of oil bubbling away in their vacuum chamber. Turbomolecular pumps are much cleaner, but very expensive. [Keegan] is attempting to design a low-cost version of a turbomolecular pump. He’s trying to use Tesla’s bladeless turbine design rather than the traditional bladed turbines used in commercial pumps. So far tests using a Dremel tool and paper discs have been promising – nothing has exploded yet!

commongroundFinally, we have [Samuel Bowman] with Seamless IoT Protocol Translation: Common Ground. Love it or hate it, the Internet of Things is going to be here for a while. Every device seems to speak a different language though . Z-wave, Zigbee, LoRa, WiFi, and a host of other protocols, all on different frequencies. Some are frequency hopping, some use mesh networks. [Samuel] is trying to design one device to translate between any of the emerging standards. Common Ground started as a science fair project connecting MQTT to Phillips Hue devices. Once [Samuel] achieved that goal, he realized how much potential there is in a universal translator box. We’re hoping [Samuel] achieves his goals quickly – it seems like new IoT standards are being introduced every day.

New projects are entering the 2016 Hackaday Prize every hour! You can see the full list right here. That’s it for the 100th Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

Standard Resistor Teardowns

March 19, 2016 by 20 Comments

What do you do, when you want an ohm? What is an ohm, for that matter? Take a wander over to the textbook definitions, and you’re soon deep in a world of coulombs and parallel infinite planes one meter apart in a vacuum that you probably only half remember from your high school physics class. It’s hard work, this metrology lark.

Of course, you can just order a resistor. A few cents each when you’re buying small quantities or much less when you’re buying a reel of five thousand, and there you have it. An ohm. Only it’s not really an ohm, more like nearly an ohm. Within 1% of an ohm is pretty good, but Vishay or Bourns or whoever don’t have the margins to get philosophical about those infinite planes when you’re only giving them a few cents.

When you REALLY want an ohm, you buy a standard resistor, and you pay a more significant sum. You’re never going to wire one of these up to bias a transistor or drive an LED, instead it’s about as close as it’s possible to get on your bench to the value it says on the box and you can use it for calibration purposes. PPM figures well in excess of the resolution of even superior DMMs sound pretty good to us!

[Zlymex] was curious about standard resistors, so performed a teardown of a few to see what they contain. And after a pithy explanation of the terms involved he’s managed to look inside quite a few of them.

Inside he finds hermetically sealed wire-wound resistors, some oil-filled wire-wound resistors, and the occasional hefty piece of manganin. He also tears down some of the hermetically sealed resistors themselves, finding both wire-wound and foil resistance elements within.

It is a curious obsession that permeates hacker culture, that of standard measurements, and it’s one we’ve covered quite a few times here. Time enthusiasts with atomic clocks like this rather beautiful discrete logic build, or voltage enthusiasts with their temperature compensated references or programmable standards. Surprisingly though, this appears to be the first time we’ve looked at standard resistors.

Thanks [David Gustafik] for the tip.

Tombstone Brings New Life To Board

March 19, 2016 by 24 Comments

Making revisions to existing PCBs with surface mount components often leads to creative solutions, and this insertion of a switch over a tombstoned resistor is no exception. According to [kubatyszko], “this is an FPGA-based Amiga clone. R15 serves as joint-stereo mixing signal between channels to make it easier on headphone users (Amiga has 4 channels, 2 left and 2 right). Removing R15 makes the stereo 100% ‘original’ with fully independent channels. Didn’t want to make it permanent so I decided to put a switch.”

Whether [kubatyszko] intends it or not, this solution is not going to be permanent without some additional work to mechanically secure the switch. We’ve tried this sort of thing before and it sometimes results in the contact area of the resistor being ripped off the substrate and separated from the rest of the resistor, rendering it useless. However, the creative use of the pads to get some additional functionality out of the board deserves some kudos.

We love creative fixes for board problems but it’s been a really long time since we’ve seen several of them collected in one place. We’d love to hear your favorite tricks so let us know in the comments below.

Third Person Driving IRL

March 19, 2016 by 31 Comments

It’s a dream come true: remote control of a real car. Besides being a lot of fun, a life-size RC vehicle has some practical applications, like performing rescue operations or delivering supplies to dangerous areas. For [Carter], [Dave], [Ryan], and [Sean], the dream became reality in the span of 24 caffeine-and-chicken-finger-fueled hours during an Ohio State University hackathon. They dubbed the system MagiKarpet because it sits in place of the floor mat and runs on pixies.

The plan was to control the throttle, brake, and steering of a Chevy Cobalt using a PlayStation controller. For added fun, a camera mounted high above the back bumper would provide a third-person view, and this feed would be displayed on a monitor in the backseat. Everything is controlled by an Arduino Mega. A beefy linear actuator works the brake and is attached temporarily with a band of Shapelock that slips around the pedal. The throttle is pushed by a lever attached to a car window motor. Another motor connects to the steering wheel with cables that can turn it 90° left and right. Although the build was successful, they ran into a couple of issues. But what’s a hackathon experience without a few problems?

The linear actuator was jammed for about an hour after some early testing, but they got it unstuck. The PS controller was borked, so they had to roll their own joysticks. The school wouldn’t let them actually drive it around because of safety (killjoys but we get it), so they put it up on a jack to demonstrate it for the judges. They took second place, though we can’t imagine what would have beat this. Check out the complete build video after the break.

You might remember these guys from last year around this time. They took first place at the same hackathon with Robottermilk Puncakes, a app-controlled pancake machine. Now that you’re hungry for pancakes, feast your eyes on this endless one.

Continue reading “Third Person Driving IRL” →

Restoration Of A Self-Crêpe Machine

March 18, 2016 by 23 Comments

A few years ago [Tweepy], one of the Hackaday readership’s global band of pancake enthusiasts, took possession of an aged “Self-Crêpe” machine. Judging by the look of the date codes on the ICs in the early 1980s, this machine cooked and sold a fresh crêpe on the insertion of a 1 Franc coin (about 17 U.S. cents in those days) for about thirty years.

Sadly, it would no longer produce crêpes. The aged control logic was the culprit, and rather than debug it [Tweepy] decided to replace it with a microcontroller (French language, Google Translate link). The one he chose (marked “RSF2127″, can anyone identify it?) came in a QFP package, so attaching it to a 0.1” prototyping board required some soldering wizardry with fine wires, but it was soon up and running. Some track-cutting and wiring into the original PCB, and the custom C code was ready to go.

The crêpe-making part of the machine features a heated roller not unlike the one in our recently featured South African endless pancake machine in whose comment thread [Tweepy] mentioned it, but appears to use only a single-sided cooking process. The roller has a round crêpe-sized raised area. To start the cooking process, a loading bath of batter is brought up under the roller which is then rotated so that the round raised area passes through the surface of the batter. As the roller turns, it cooks the crêpe, which is then diverted from the roller to the output chute. The whole process relies on a reservoir of pre-made batter, sadly it’s not a crêpe replicator. On the other hand, a single crêpe takes about 40 seconds to create, and the machine can produce them on a continuous basis as long as you keep it stocked with batter.

We like the crêpes, we like the machine, and we like what [Tweepy] has done with it. If any of these machines made it beyond the borders of France, we’ve never seen one in our corners of the Anglophone world. This is a shame, for who wouldn’t want one of those next to the kettle and microwave oven in their hackspace! They would have needed to work on that name, though, for the English-speaking market.

We’ve recently done a round-up of pancake-related hacks here at Hackaday, so there is no point in repeating it. This is however not the first vending machine hack we’ve seen. There was this stealth-upgraded soda dispenser, this Tweeting beer dispenser, or how about this open-source software machine that definitely didn’t vend.