One of our readers just sent us a tip about this interesting kickstarter project. [Turner Hunt] is bringing carbon fiber manufacture into the hands of makers — at considerable cost savings!
So how does it work? The machine wraps the filament around the workpiece, not unlike a CNC lathe in reverse. Actually it’s kind of a new breed of 3D printer! As the machine feeds the filament, it dips it through a bath of epoxy resin before being wrapped around the workpiece. A finishing step wraps heat shrink tape around the finished project using a heat gun, which then provides a glossy surface finish very similar to commercial carbon fiber products.
By purchasing carbon fiber filament and epoxy resin and using this machine, you can create structural carbon fiber tubes for about 80% less than they would cost commercially. The system comes with its own software that controls the machine via g-code, and you can also specify different wrapping patterns for different applications. While tube-shapes work best, you can also wrap other shapes including flat bars, wing skins, turbine blades and more — anything that is wrappable and under 6″ in total diameter. Is anyone else thinking about custom wrapped quadcopter frames?
Robert’s Rocket Project has been going on for a long time. It has been around so long that you can go all the way back to posts from 2001, where he talks about getting his first digital camera! The site is dedicated to his pursuit of liquid fueled rocket engine building. It’s a great project log and he has finally come to the point where he will be testing his first flight vehicle soon.
His latest project is a 250lbf regeneratively cooled engine. It uses kerosene as the fuel, and liquid oxygen as the oxidizer. The neat thing is he utilizes the temperature change of the liquid oxygen expanding to cool the chamber and nozzle before being burned. This allows for a very efficient and powerful combustion of the fuel. He has some videos of testing it on his site, we just wonder why he doesn’t host them on YouTube or something…
Anyhow, there’s more than enough info on his site to try and recreate some of his experiments, but perhaps you should start here instead: How to Design, Build and Test Small Liquid-Fuel Rocket Engines.
When tea lights just won’t do, why not move up to a 5 channel LED candle simulator?
Halloween is fast approaching. Peter’s local hackerspace, The Rabbit Hole had a meeting to carve pumpkins and talk Halloween hacks. After seeing how poorly a tea light illuminated a medium size pumpkin, this hack was born. We’ve seen LED jack-o’-lantern hacks before, but this one was worth a second look.
In true hackerspace style, [Peter] used what was available to him. A PIC12F508 is the heart of the project. The 12X508/9 series has been around for at many years, and is still a great chip to work with. We remember using the ‘C’ version of this chip to bypass region locks on original PlayStation systems. [Peter] created a simple circuit with two basic modes. In “value mode” the 508 drives LED’s directly from its I/O pins. This limits the total output to 60mA. In “premium mode”, some 2N3904 NPN transistors are brought in to handle the current. This allows the PIC to drive up to 5 LEDs.
Candles can be tricky to simulate with LEDs. [Peter] used 5 independent 16 bit linear feedback shift registers to generate pseudo random bit streams. The effect is quite impressive. A “wind simulation” completes the illusion of a real flame. Continue reading “LEDs turn the heat up on flameless pumpkin lights”
The folks over at Valve Corporation have been busy. Just this week they have made three announcements regarding the future of their company; SteamOS, a linux-based operating system, Steam Machines (for running SteamOS), and the one we’re most interested in, the Steam Controller, an open controller. Not to worry though, the controller is not exclusive to the Steam Machines!
This is why we’re intrigued:
The Steam Controller was designed from the ground up to be hackable … We plan to make tools available that will enable users to participate in all aspects of the experience, from industrial design to electrical engineering.
We’re curious to see what that exactly means, but it definitely sounds promising! We know that Valve already takes in tons of customer feedback through their Steam Community and Workshop contributors, but how open is this controller really going to be? To read more about it as the information unfolds, check out the topics in the Steam Universe forum.
If you’re interested in joining the hardware beta, head on over here, but space is very limited.
Sometimes it’s fun to take a step back from the normal electronics themes and feature a marvelous engineering project. This week’s Retrotechtacular looks at a pair of videos reporting on the progress of the Bay Area Rapid Transit system. Anyone who’s visited San Francisco will be familiar with the BART system of trains that serve the region. Let’s take a look at what went into building the system almost half a century ago.
Continue reading “Retrotechtacular: Building BART”
Let’s rollback the hobby electronics calendar a few decades with [myvideoisonutube’s] alarm activation control circuit using a matrix style phone keypad. The circuit is quite old using CMOS 4081 with 4 ‘AND’ gates to hardwire the access code. [myvideoisonutube] references [Ron’s] “Enhanced 5-Digit Alarm Keypad” schematic for this build changing the recommend keypad with a more common matrix style keypad found in touch pad phones. These types of matrix keypads wouldn’t work outright for the input so he cut some traces and added hookup wires to transform it into a keypad with common terminals and separately connected keys. We love seeing such hacked donor hardware even when it requires extensive modifications. [Ron’s] source circuit included a simple enough to build tactical button keypad if you can’t find a suitable donor phone.
Learning how to use mostly discrete components instead of a microcontroller would be the core objective to build this circuit outside of needing a key-code access point or other secure 12 V relay activated device. Such a device would be quite secure requiring a 4 digit “on” code and 5 digits for “off”. You couldn’t just pull off the keypad and hotwire or short something to gain access either. The 4 digit on “feature” does knock the security down quite a lot. However, all keys not in the access code are connected to the same point so you could increase your security by using a pad with more keys.
On [Ron’s] site you will find a detailed construction guide including top and bottom view for placement of all the components on veroboard. Join us after the break to watch [myvideoisonutube] demo his version.
Continue reading “5 Digit Security Code Activated Relay Using Mostly Discrete Circuitry”
Here’s a handy hack for an Android controlled, Arduino driven, RGB light setup.
[Kerimil] recently wrote up this project on the Arduino.cc, and is sharing all of the source code and plans. While many of our seasoned Arduino-lovers can easily throw together the code for an RGB LED circuit in their sleep, [Kerimil] also threw in the Android app, and the source file to be modified in App Inventor, an Android app development program originally released by Google, but now maintained by MIT.
We’ve seen many commercial versions of this product, but it’s nice to see one that can be easily hacked to our liking. Next up is writing an app to use the phone’s camera to identify colors and reproduce them with the LED! While you’re at it, why not mix it with an easy to build infinity mirror!
To see the board and app in action, check out the video after the break.
Continue reading “Android Controlled RGB Lights”