[Nurdrage] puts out a lot of neat videos, mostly about home chemistry. For the home chemist it is occasionally desirable to pull a vacuum. For example, a potentially dangerous chemical can be boiled and distilled at a much lower temperature than at atmospheric pressures.
However, there’s a problem with just going to the local import store and buying the first vacuum pump on the shelf. They are primarily designed for atmospheric gasses and tend to melt when exposed to solvents. If you’re a big university or a commercial lab this is no problem. You just drop three grand on a Teflon diaphragm pump or a liquid nitrogen trap. For the home chemist who’s already having enough trouble just buying the chemicals needed for neat experiments, this is not an option.
[Nurdrage] demonstrates the proper usage of a much cheaper option: an aspirator vacuum pump. You might remember something similar from high school chemistry. School pumps generally use flowing tap water to produce the vacuum. [Nurdrage] is saving water by using a fluid pump and a reservoir to drive his aspirator.
Aspirator pumps use the Venturi effect to create a vacuum. These devices are cheap because there are no moving parts. We looked it up and the one he is using costs ten US dollars on fleabay. It can pull enough vacuum to boil water below room temperature.
The video is really good and provides a lot of useful information. It also seems like a really useful device for other hacking tasks outside of home chemistry. Video after the break.
Continue reading “Cheap Vacuum Source For Working With Dangerous Chemicals”
If you are doing a senior design project in engineering school, it takes some guts to make a robotic duplicate of the school’s president. He or she might be flattered, or completely offended. Us? We laughed out loud. Check out the video below. Spoiler: the nose/moustache wiggle at the end kills us every time.
The project uses a variety of parts including a plastic mask, an Erector set, and the obligatory Arduino with an MP3 shield. There are many articulated parts including eyes, nose, mouth, and wiggly moustache. The face uses RC servos, although [gtoombs] says he’d use stepper motors next time for smoother motion.
Continue reading “Robo Face Speaks”
We had to do a double take when we saw this kickstarter campaign video – and we bet you will too. It seem as if some company called [Infento Rides] took generic 80/20 aluminum extrusions and built a viable commercial product out of it – that’s not something you see everyday. 80/20 is meant to be something that engineers use to build things like test rigs and manufacturing fixtures. It’s not exactly an item designed for the consumer or end user. But we think the DIY/teaching aspect of this idea really has
If you’re looking for [Santa] to put this under the tree this Christmas, you might be disappointed as it’s not exactly on store shelves just yet since the kickstarter campaign just ended – but we wish them well, and hope they come through.
If you’re old enough you may remember Erector Sets (they were mechanical equivalent of the 200-in-1 electronics kits) back in the day. Well, this type of product brings back memories of both. It’s a perfect tool for getting kids interested in making – sure, they aren’t “making” much, but we all start somewhere.
The one thing we would like to see is a more open-source type kit like the Chibikart. That and something a little less then the $300-$500 price range. But can you really put a price on teaching a child to build something, and starting that fire inside of them? Maybe not.
Continue reading “80/20 Extrusion Goes Main Stream”
I still remember the first time I saw a satellite, I was 12 years old and was camping far away from the city lights. As I gazed up at the night sky, I could actually track satellites with my naked eye as they zoomed across the night’s sky. It was amazing. Nowadays, it’s getting harder to spot relatively small satellites with light pollution from large cities.
The International Space Station (ISS) on the other hand is a large piece of hardware — it’s about the size of a football field, and according to NASA it’s the second brightest object in the night sky. So why don’t we see it more often? Well, part of the reason is that you don’t know where to look. [Grady Hillhouse] set out to change that by building a what is basically a 2 degrees of freedom robot arm that will point you to where the ISS is at any given moment.
[Grady] uses a stepper motor for the azimuth, and a standard servo for the elevation, all powered by an Nucleo F401 development board, and an Adafruit motor shield and slip ring. The structure is made using some Erector set like parts from Actobotics.
He wrote the code from this open source project here. He’s currently cleaning up his code, and says he’ll be posting it up shortly. In the mean time, you can watch a video detailing the build in the video after the break. Or if you can’t wait, you can visit NASA’s web site to receive email or SMS messages on when the ISS is view-able in your hood.
Continue reading “It’s 10 PM, Do You Know Where Your Space Station Is At?”
16A lot of engineers, scientists, builders, makers, and hackers got their start as children with LEGO. Putting those bricks together, whether following the instructions or not, really brings out the imagination. It’s not surprising that some people grow up and still use LEGO in their projects, like [Steve] who has used LEGO to build an optics lab with a laser beam splitter.
[Steve] started this project by salvaging parts from a broken computer projector. Some of the parts were scorched beyond repair, but he did find some lenses and mirrors and a mystery glass cube. It turns out that this cube is a dichroic prism which is used for combining images from the different LCD screens in the projector, but with the right LEGO bricks it can also be used for splitting a laser beam.
The cube was set on a LEGO rotating piece to demonstrate how it can split the laser at certain angles. LEGO purists might be upset at the Erector set that was snuck into this project, but this was necessary to hold up the laser pointer. This is a great use of these building blocks though, and [Steve] finally has his optics lab that he’s wanted to build for a while. If that doesn’t scratch your LEGO itch, we’ve also featured this LEGO lab which was built to measure the Planck constant.
Remember when building your own 3D printer was a big deal? We’re starting to think that building your own laser cutter might be the next hot topic.
Boasting a 16,000 square-foot facility, the Dallas Makerspace is an impressive collaboration of local artists, engineers, makers, and thinkers. Recently they embarked on building a serious laser cutting machine. They chose to go with the an open-hardware design rather than buying an off-the-shelf unit. What they built is based on the Lasersaur plans. (Another popular open-source build is the buildlog.net unit.)
They ended up with a huge 24″ by 48″ cutting bed and with a laser tube rated for 100 watts continuous output. It can cut 1/2″ plywood and 10mm acrylic with ease. The entire machine is built from 20mm Misumi aluminum t-slot extrusions, making more like a giant erector set then a commercial built machine. We hadn’t seen too many of the Lasersaur builds out in the wild, so we thought you might like to see one too.
Now, before you start ordering parts to build your own, you should know that a top of the line build like this will run you about $7-10k. But by comparison if you were to go with something with the same cutting area and power, you’d be looking at something like the “Epilog Fusion 40” at a whopping $40k. With that said, we expect to see more budget laser cutter builds. Cost can be cut dramatically when you go for a smaller machine, with less cutting area, and less power. With that, you can use less expensive steppers, drivers, and frame. We suspect a little as $700 for a smart shopper could yield a very respectable laser cutter.
If you’re interested in learning more about the Dallas Makerspace, we took a video tour back in early 2014.
If you’ve ever used an old-school analog oscilloscope (an experience everyone should have!) you probably noticed that the trace is simply drawn by a beam that scans across the CRT at a constant rate, creating a straight line when there’s no signal. The input signal simply affects the y-component of the beam, deflecting it into the shape of your waveform. [Steve] wrote in to let us know about his home-built “oscilloscope” that works a lot like a simple analog oscilloscope, albeit with a laser instead of a CRT.
[Steve]’s scope is built out of a hodgepodge of parts including Lego, an Erector set, LittleBits, and a Kano Computer (based on a Raspberry Pi). The Pi generates a PWM signal that controls the speed of a LittleBits motor. The motor is hooked up to a spinning mirror that sweeps the laser across some graph paper, creating a straight laser line.
After he got his sweep working, [Steve] took a small speaker and mounted a mirror to its cone. Next he mounted the speaker so the laser’s beam hits the mirror on the speaker, the spinning sweep mirror, and finally the graph paper display. The scope’s input signal (in this case, audio from a phone) is fed into the speaker which deflects the laser beam up and down as it is swept across the paper, forming a nice oscilloscope-like trace.
While [Steve]’s scope might not be incredibly usable in most cases, it’s still a great proof of concept and a good way to learn how old oscilloscopes work. Check out the video after the break to see the laser scope in action.
Continue reading “DIY Oscilloscope with a Scanning Laser”