Sub $300 CNC, If You Have A 3d Printer

January 25, 2016 by 37 Comments

[Allted] has designed a CNC machine that you can print yourself; adding conduit, bearings, and the standard vitamins to bring it to life. The CNC machine uses a mechanical design similar to an etch-a-sketch, though instead of the maze of pulleys and cable it uses four stepper motors to do the X and Y translation. The machine looks to be about as accurate as a Shapeoko, and is able to handle light cutting in aluminum.

The coolest part is the extensibility of the printer. For example, [Allted] needed to print a lot of parts to make orders of the kit. So, he built a 4 headed 3D printer by copying blocks of the design, and tying them all to the same belt. The design also seems to be a little more resistant to dust and debris than some homemade rigs. The CNC won the Boca Bearings design competition. If you’d like to build one yourself, [Allted] has all the instructions with print setting recommendations on his website.

Bismuth Crystals Hold Magnet Suspended For 100 Years

January 25, 2016 by 37 Comments

[NightHawkInLight] has been playing around with the diamagnetic properties of bismuth. Diamagnetic materials get a lot of attention due to their strange ability to produce the opposite of the magnetic field going through them. In simpler terms, metals like iron are attracted to magnets; metals like bismuth repel them.

[NightHawkInLight] built his own interpretation of a common lab example used to demonstrate this remarkable property, a levitator. A levitator is made by sandwiching a magnet between two plates of diamagnetic material. One of the plates is given a magnetic field opposite of the magnet underneath it by a stronger magnet placed some distance away. When this is done, the magnet in between wants to repel away from the plate above, only to find that as it gets closer to the plate below it is equally repelled, creating a stable system.

Eventually the magnet above will need realignment, but [NightHawkInLight] assures us this is only once every 100 years. Video after the break. Continue reading “Bismuth Crystals Hold Magnet Suspended For 100 Years” →

Raspberry Pi Zero Cluster Packs A Punch

January 25, 2016 by 91 Comments

If you could actually buy 16 Raspberry Pi Zeros, you might be able to build your very own Raspberry Pi Cluster for only $80! Well… minus the cost of the board to tie them all together…

A Japanese company called Idein is developing a Raspberry Pi module called the Actbulb for computational sensing and data analysis. In order to perform internal testing they decided to make things easier for themselves by developing a board to allow them to plug in not one, not two, but sixteen Raspberry Pi Zeros:

Since we will use Pi’s GPU for image processing, deep learning, etc. We need real Pis but not just Linux machines. Another reason. It can be used for flashing eMMCs of our devices via USB ports when we have to do that by ourselves.

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Homemade Exoskeleton Lifts Mini Cooper With Ease

January 25, 2016 by 37 Comments

As some of you may or may not know, I’m interested in everything exoskeleton related. I’ve been messing around with my own designs for the past year or so, and just this past weekend, tested out the latest lower body design. There are a lot of boring (and some would say safe) ways to test this. But that’s no fun. For my test I used the lower-half of the exoskeleton to pick up a Mini Cooper.

exoskeleton-curlYou might remember my original upper-body design which was something I threw together in my garage as a proof of concept. It worked well for what it was, and surprisingly, took the internet by storm — amassing over a million views in a single week for a video of me curling 170lbs in my backyard. The fire had started — I knew I had to make something better. And that was the beginning of my quest to build a full-body powered exoskeleton.

The biggest problem with the original was a lack of back support — it didn’t matter how much weight I could lift, it was still my feeble human skeleton taking the weight. So it was time to go back to the drawing board, and start the design from the ground up. Continue reading “Homemade Exoskeleton Lifts Mini Cooper With Ease” →

Bone Up On Your Multiplication Skills

January 25, 2016 by 5 Comments

John Napier was a Scottish physicist, mathematician, and astronomer who usually gets the credit for inventing logarithms. But his contributions to simplifying mathematics and building shorthand solutions didn’t end there. In the course of performing the many calculations he needed to practice these subjects in the 1500s, Napier invented a kind of computing mechanism for multiplication. It’s a physical manifestation of an old system known as lattice multiplication or gelosia.

Lattice multiplication makes use of the multiplication table in order to multiply huge numbers together quickly and easily. It is thought to have originated in India and moved west into Europe. When the lattice method reached Italy, the Italians named it gelosia after the trellised window covering it resembled, which was commonly used to keep prying eyes away from one’s possessions and wife.

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Repair And Calibration Of Valhalla Programmable Precision Standard

January 25, 2016 by 5 Comments

Precision standards are the pinnacle of test and measuring instrumentation. Well engineered, sure, but also beautifully built and a feast to look at, no matter how old they are. [Shahriar] at “The Signal Path” often gives us the skinny on such equipment. In the latest episode, we get a look inside a Valhalla 2701C Programmable Precision DC Voltage Standard.

Even by 1990 standards, it is a fairly basic instrument, capable of producing just DC Voltages from 100nV up to 1200V. But it is a reference standard, so the output is highly stable, accurate and precise.  He snagged it from eBay on the cheap but transport seemed to have caused some damage. It would switch on and relays would click when he pressed buttons, but the 7-segment LED display was blank. Luckily, opening the top cover fixes that problem – just a loose connection between the front display and the main board. Examination also shows that adding a 120mA DC current range would require adding additional components on the main board so his hope of doing a quick firmware upgrade is short lived.

[Shahriar] takes the opportunity to walk us through the various sections of the well built unit. It’s apparently seen some repairs during it’s life. A few capacitors look changed, and a relay housing has seen damage from a soldering iron. The digital section is mainly the 6800 micro controller, an EPROM and a NVRAM, and it generates the PWM signals needed for producing the output voltages. A highly precise reference signal is essential for such equipment, and this one uses the LM299 with a “custom” suffix meaning it was specially screened and binned. He does a quick calibration run, but it’s obviously rushed and doesn’t produce stable results. But that could also be due to the low quality cables he used, or a number of other factors. Calibrating such equipment is a job demanding both time and patience.

While this may not knock your socks off. For that, check out this post where [Shahriar] does a tear down of the one million dollar Labmaster 10-100zi Oscilloscope, or this other one where he plays around with a half a million dollar oscilloscope you’ll probably never use, much less own.

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Overunity, Free Energy And Perpetual Motion: The Strange Side Of YouTube

January 25, 2016 by 210 Comments

Spend enough time on YouTube, and you’ll eventually find yourself in one of the many dark corners hiding within it. No, I’m not talking about the comments. In this case, I mean the many videos dedicated to free energy, overunity devices, perpetual motion machines, or anything else that violates the laws of thermodynamics by trying to get out more energy than is put in. The human race has been reaching for impossible dreams of perpetual motion and free energy for just about all of recorded history. Now it’s convenient to find them all in one place.

searl_effect_generator-shot0001Browsing the tubes, it’s easy to break free energy videos down into two major groups: enthusiasts and scammers. Catching a scammer is easy – they’re looking for money. Somewhere in the video or description will be a link to a website with more information. Eventually that will lead you to a place where the scammer attempts to part you and your hard-earned money.

Names like John Searl, Muammer Yildiz, and M. T. Keshe go here. Searl especially deserves note because he’s been at it for decades.  Supposedly, his “Searl Effect Generator” SEG has been built several times, but the prototypes generate so much power they create their own anti-gravity field and fly off into space. Obviously this man and his staff need your money to continue their work. Scammers deserve disdain and public shaming. These are the folks who know their “discoveries” are nothing more than snake oil.

On the other side of the coin lie the enthusiasts. These are the backyard tinkerers, the ones who put down their computers, pick up their tools, and try to build something. Sounds a lot like the average Hackaday reader, doesn’t it? I have to admit I went into this article with the same disdain for the enthusiasts that I have for the scammers, possibly even more. In some cases, these are the folks who truly believe they can have a chance to violate the laws of thermodynamics. Inevitably these folks fail to build free energy generators, overunity devices, or whatever their pursuit is, but they all do seem to learn something in the process. A lot can be said about the builds themselves. Some of these are awesome devices. Even if they don’t work for their intended purpose, they are great demonstrations of magnetism or chemistry. This is where I had a change of heart. If someone wants to spend their time working on an impossible hack, then more power to them. I may not think they have any chance of success, but at the very least, they’ll learn how to build.

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