[Adam] over at Makefast Workshop writes about some of the tests they’ve been running on their 3D printer. They experimented with pausing a 3D print midway and inserting various materials into the print. In this case, sand, water, and metal BBs.
The first experiment was a mixture of salt and water used to make a can chiller for soda or beer (the blue thing in the upper right). It took some experimentation to get a print that didn’t leak and was strong. For example, if the water was too cold the print could come off the plate or delaminate. If there was too much water it would splash up while the printer was running and cause bad layer adhesion.
They used what they learned to build on their next experiment, which was filling the print with sand to give it more heft. This is actually a common manufacturing process — for instance, hollow-handled cutlery often has clay, sand, or cement for heft. They eventually found that they had to preheat the sand to get the results they wanted and managed to produce a fairly passable maraca.
The final experiment was a variation on the popular ball bearing prints. Rather than printing plastic balls they designed the print to be paused midway and then placed warmed copper BBs in the print. The printer finished its work and then they spun the BB. It worked pretty well! All in all an interesting read.
Can you make a spectrometer for your home lab all from materials you have sitting around? We might not believe it from a less credible source, but this MIT course does indeed build a spectrometer from foam board using two razor blades as the silt cover and a writable CD as the diffraction grating. The coolest part is removing the metal backing of the CD.
Hackaday reader [gratian] tipped us off about the course available from MIT courseware called Nanomaker. It boils down some fairly complicated experiments to the kind one can do in the home lab without involving thousands of dollars of lab equipment. The whole point is to demystify what we think of as complicated devices and topics surrounding photovoltaics, organic photovoltaics, piezoelectricity and thermoelectricity.
Spectrometers are used to analyze the wavelengths of a light source. Now that you have a measurement tool in hand it’s time to build and experiment with some light sources of your own. Here you can see an LED that is the topic of one of the course labs.
If you have a bit of background in chemistry this is a good step-by-step guide for getting into these types of experiments at home. It reminds us of some of the really cool stuff [Jeri Ellsworth] was doing in her garage lab, like making her own EL panels.
Continue reading “Bring Doping, Microfluidics, Photovoltaics, and More Into the Home”
[Shahriar Shahramian] is playing with some liquid nitrogen in order to see how various components react to extremely low temperatures. After the break you will find forty-one minutes of video in which he conducts and explains each experiment. This does have practical applications. If you’re designing hardware for use in space you definitely need to know how the hardware will be affected. We’ve actually seen test rigs built for this very purpose.
During the presentation he doesn’t water down the concepts observed, including the equations governing each reaction to temperature change. If you’re in the mood for a little bit lighter faire you should check out some of the liquid nitrogen cooking hacks like this super-cold cocktail pops project.
Continue reading “Measuring how components react to extremely cold temperatures”
Finally an Arduino shield that does nothing
The folks at Evil Mad Scientist labs have finally created the Googly Eye Shield for Arduinos. With it’s pass-through .100 headers, it adds googly eyes to your Arduino projects. Of course,
instead of in addition to the googly eyes you could add a breadboard, making it somewhat useful. A million fake internet points goes to the first person to implement Xeyes on this thing.
Phat beats from kids toys
[Ville] couldn’t afford an Akai MPC for laying down some beats. Wanting a real tactile interface, he hacked this kid’s toy. It’s just an RCA cable attached to the tiny chip inside the toy. The new line out goes to his mixers where he does some pretty impressive stuff.
Mona Lisa is Vigo the Carpathian
What did we just say about real-life Xeyes? [Geert] just made a print of the Mona Lisa follow you around the room with her eyes (Dutch, translation). The build is a pair of servos and a DIY motion capture app running on a laptop. Now we need to find a print of Vigo…
Quantifying heat sink efficiencies
[Mike] is an experimenter at heart. He was wondering about the efficiency of small, clip-on heat sinks versus the ones we use to defrost frozen food. The results are exactly as you would expect, but he did find something interesting – his experimental technique didn’t find much of a difference between thermal paste/grease/pads and no thermally conductive material.
Mini-fig sized R/C LEGO car
The guys at Brickmodder.net took a car from a LEGO set and made it remote control. The drive train and steering both use servos controlled by the smallest 3-channel receiver they could find.
This project provides an opportunity to conduct near space experiments. The flight computer, BalloonSat Extreme, is controlled by a BASIC Stamp 2pe. The complete BOM with PCB artwork is provided. There is enough hardware to control cameras, servos, a Gps, and five digital I/O. The computer is also equipped with a 12 bit ADC to log experiment results. The device seems limited to 30KB of storage. Though the author suggests this memory limitation is more than adequate, we are wondering if an implementation of the Nyquist sampling theorem is in use at all. For further reading the author has provided information regarding Amateur Radio High Altitude Ballooning.
After the overwhelming response to the Hackit we posted about automated hard drive destruction last fall, we finally decided to test out some thermite hard drive destruction ourselves. This has been done on The Screen Savers but they did not show up close results of the platters. So, aluminum and black iron oxide were procured through eBay, and until it arrived we watched some YouTube videos that showed a lot of fire and no real results. We decided to see what it would take to completely obliterate a drive.
With the amount of personal data stored on your computer, we all understand the importance of destroying the data that is stored on the platters of a hard drive before disposing of it. There are many ways to destroy a hard drive; software, physical disassembly, drills, hammers, magnets/electromagnets, and acid, but none are quite as outrageous and dangerous as thermite. That’s what we’re going to do here today. Follow along for pictures and videos of the results.
Continue reading “How-to: Thermite hard drive destruction”