[Hubert] sent in his experiments using HDDs, CDROMs, speakers, and other components to make an XY laser plotter. Those carefully reading will note, its not all three to make one plotter, but rather three plotters each using a separate system. The setups have their advantages and disadvantages, and [Hubert] is sure to point them out; including circuit diagrams and pictures to help you on your own trials.
There is a little difficulty in reading English not so good, but considering we’ve never seen a single-laser vector plotter done before (spirographs come close, and no one wants to wait 85 seconds) it’s still very impressive.
At first we thought this looked hastily thrown together and quite possible useless. Then we watched the video, embedded after the break, and realized it is quite a handy bench sander. [Mhkabir] opened up an older hard drive, removed the read head, and added a piece of carefully cut sand paper. When you hook it up to your bench supply you’ve got a small sander ready to use. We can’t wait to try it on some small PCB edges. Now that we’ve seen a sander and a chop saw, we wonder what’s next?
Continue reading “HDD power tools: the sander”
Sometimes your project needs a lot of non-volatile ROM, right on cue [Matthew] let us know how to not only connect, interface, read, and write to SD cards with a PIC over serial, but also how to do the above mentioned with an old PATA HDD. For those without a PIC/serial connection don’t fret, [nada] let us know about his Bus Pirate SD card hack, of which our personal favorite part is the creative use of an old 5.25″ floppy connector as the SD card socket.
Strobeshnik is a somewhat different twist on the hard drive clocks we’ve seen in the past. Though still technically using a POV effect, the Strobeshnik displays the numerals instead of a line. By altering strobe timing of an LED behind a platter with the numbers cut into it, he can display whichever number he wants. We think this is pretty slick.
This device is lovingly called the SPINmaster. [Linux-works] built it to spin up multiple hard drives before the motherboard starts up. It detects the power-up from the PSU and uses a relay to hold the motherboard in reset, indicated by the red LED. Each of four relays then spins up a hard drive and illuminates the green LED when ready. Once all green lights come on the reset relay shuts off and the bios starts up. This type of staggered startup takes a lot of the load off of an under-powered PSU. He’s posted firmware and there’s a schematic available too. We took a look at his video but there’s not much to see as it’s just the inside of the machine while it boots up.
This is the multichord, a one-string musical instrument built by [Christopher Mitchell]. The string is a 20 pound mono-filament thread stretched between a wooden bridge and the read/write head of a hard drive. The idea is that the vibrations of the string are picked up and amplified acoustically by the sounding box that serves as the body of the instrument. The frequency of vibration (pitch) is changed by adjusting the tension of the string through the application of various voltages to the HDD head. A relief spring has been added to the head to take the resting tension off of it, making it a lot easier to fine-tune the settings for each note. A keyboard made of twelve buttons selects each different pitch as the string is plucked.
[Christopher] is continuing to post great hacks; we’ve seen a glove input and a giant VU meter from him in the past. Take a look at the multichord in action after the break.
Continue reading “HDD actuated acoustical instrument”
[Dennis] got snowed in after the biggest storm in the history of the state hit. Like any good hacker he didn’t let the time go to waste. He decided to dig out his Neo Freerunner to give it a decent battery and a new OS.
The original battery for the Freerunner has a controller board integrated into the package. [Dennis] pulled out the board and attached it to a portable DVD player battery. After running it through a discharge cycle with another hack of his, the board learned the new battery capacity. The larger battery plus a fast-charger from SparkFun required a larger case. He made it happen by combining a 2.5″ HDD case with the original body courtesy of some JB weld. The final portion of the hack was to load up Android which is as simple as untarring the package onto an SD card.
It’s a bit big, but the battery will last and he’s got an open platform. Nice work!