Mini Arc Furnace Melts Its Way Into Our Hearts

June 16, 2015 by Theodora Fabio 44 Comments

[Grant Thompson], aka “The King of Random,” threw caution to the wind when it came to his latest awesome project – a mini electric arc furnace (EAF) (YouTube link). [Grant] uses a refractory brick as a furnace and crucible for the molten metal. He wears eye protection and a respiratory mask as he cuts up the brick – a good idea, since you don’t want to inhale any of that dust. The electrode grips are made with things you can find at a hardware store, including copper wire and coupling, and 2 pairs of vice-grip style pliers. The copper wire is stripped and attached to the metal handle of the pliers using hose clamps. The pliers are now functional electrode grips- just put a carbon rod in each grip and hold them close to each other…but not without protection! [Grant] harvested the carbon rods from the cells of 6V lantern batteries – dead batteries work just as well for this. It’s also a better bet to do this outdoors with decent ventilation and away from anything flammable. [Grant] realized that the rods from the batteries have a wax-like coating on them that takes about 30 seconds to burn off in spectacular flames the first time they make electrical contact. However, you can purchase carbon rods by themselves if you want to avoid ripping open batteries and possibly setting yourself on fire. The mini EAF runs on a welding power supply [Grant] made from microwave oven transformers (YouTube link).

When it’s time to melt some metal, the scrap metal is placed into a bowl drilled into the brick. Using the electrode grips, the carbon rods are placed into the brick’s pre-drilled holes. It only takes ten seconds to melt pure zinc – do NOT do this with galvanized steel or brass castings, as zinc oxide is very hazardous to your health.

In the videos featured below, [Grant] shows a variety of metals are no match for his mini EAF. He even manages to melt rocks from his backyard! It goes without saying that an EAF (video link) can be very dangerous. When you’re dealing with high voltage, plasma, white-hot molten metal, and toxic fumes, you better know what you’re doing (or have a great life insurance policy). [Grant] has a penchant for showcasing projects that can make an OSHA inspector cringe, but you have to admire his gumption!

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An Oven Controlled Crystal Oscillator Replacement

June 13, 2015 by Brian Benchoff 7 Comments

The HP 5328 Universal Counter is all the counter you’ll ever need. It’s rugged, does its job well, and like all old HP gear, keeps on going. When it breaks, though, that’s a problem.

[Tom] had an 5328 Universal Counter with a broken Oven Controlled Crystal Oscillator. This is the HP 10544 OCXO and replacements are pretty spendy. Instead of buying a vintage unit, [Tom] decided to make a replacement.

The OXCO in the HP 5328 is just an option. If the frequency counter has this option installed, a 30-pin edge connector in the counter is stuffed with a little PCB. Like all HP gear, the schematics are readily available, and the original OXCO can be quickly reverse engineered.

The design of the replacement is fairly straightforward. A 10MHz OXCO from Oscilloquartz is used, powered from the 28V rail in the 5328 with a simple switching regulator. Apart from that, it’s just an inverter to get the logic levels correct, and a small, multi-turn pot to calibrate the new OXCO. The completed unit is much smaller than the original OXCO option, so it can be plugged directly into the 30-pin card edge slot, leaving the gigantic standoff inside the frequency counter as a reminder of days gone by.

Review: Stickvise Needs A Place On Your Bench

June 13, 2015 by Mike Szczys 45 Comments

Stickvise is a simple device for a simple problem. It holds a work piece while you work on it. Most obviously this means a PCB for soldering, but there’s a twist of versatility that will make it work for a wide range of needs. Being someone who has often used the roll-of-solder-to-hold-a-circuit-board-down trick, only to upset the apple cart when I run out solder, this is a great little tool to have within arm’s reach. For those that already have a PCB vise, how often do you need more than one? How rarely do you need something that large? And if you’re lucky enough to have a microscope for soldering this is a perfect fixture for moving a board to and from without adjusting the focus.

Details of the Design

Simplicity. This is three pieces of aluminum bar-stock, some steel rod, nylon jaws, two springs, and some fasteners. It all works extremely well. To load up a new circuit board I loosen the wing nut and squeeze the clamp shut. Hand tightening the nut doesn’t take much force and it hasn’t slipped for me at all despite moving it around the bench for several days. Once set, the board can be taken out and flipped over easily thanks to the springs.

The extensibility here is key. As it stands, the nylon jaws have a V-groove to hold a board. If you need to support much taller boards you can always put some standoffs between the aluminum and the nylon jaws.

Better yet is the ability to design jaws for your own needs. [Alex Rich], Stickvise’s creator, already has a number of STL files available so that you may print out your own. The “fingers” on the custom jaw shown here interlock with the ones on the opposite side. But my favorite is an articulated set of “third-hand” style jaws based off of the PCB probe jig [Anool] covered back in May. There are even plans to make a parametric STL file so that printing larger or taller jaws doesn’t require a CAD modeling session.

If the range of the vise is too narrow you can simply replace the center bar with a longer one (source yourself or purchase from [Alex]) — the fixed aluminum end is secured with a set screw. This can even be used as a type of stretcher by reversing the spring jaw. I couldn’t think of an application in my own shop for this but you never know.

Stickvise Roots

If you have an eagle eye you’ll have noticed the Jolly Wrencher with “Hackaday Approved” next to it on the Stickvise. When [Alex Rich] started refining his original design he posted about it as a project on Hackaday.io. It didn’t take long to grab our attention and, after tossing around the idea a bit we approached [Alex] about his plans for manufacturing and how Hackaday might figure into that. I love seeing hardware come to life like this; it puts an artisanal spin on the things I choose to have in my lab.

Conclusion

It’s so simple you could build it, but for me the production quality is well worth buying it instead. It’s simple and durable, with the ability to be specialized for a number of different purposes. I wish I had had it when populating the board I’ve been showing off in these pictures (the LayerOne Badge from this year). If you do any work with circuit boards at the bench the Stickvise is a solid entry on your must-have-tools list.

World’s First Internet Connected Lawnmower

June 10, 2015 by James Hobson 16 Comments

Okay so this IOT is getting a bit out of hand. Introducing the world’s first(?) tweeting, internet connected, lawnmower.

[Michel] recently bought one of those new-fangled cordless lawn mowers by EGO. It runs off a 56V lithium ion battery pack, and apparently, works pretty well. Since it has plenty of on-board power, he decided to strap a 64MHz PIC18F25K22 to a ESP8266 and connect it to the internet. That part number has been taking the world by storm and it’s totally freaking awesome. The ESP8266 is a tiny WiFi module that is controllable over a serial port — and it only costs $5. Hello IOT-everything.

Anyway, to avoid voiding his warranty, [Michel] using non-invasive sensors to collect data — A series of hall effect sensors and magnets to be exact. One detects when the cutting system is engaged, and another magnet and sensor pair counts wheel revolutions. In the end, this gives you data on how far you pushed the mower, how long you spent cutting, and how long you were out there. When the job is done, you have the option to push a tweet with your stats. Woo!

He does admit, the tweeting feature is more there just to annoy his friends.

Super Cheap Vac Attachment Helps Find Small Dropped Parts

June 10, 2015 by Rich Bremer 27 Comments

It’s pretty much guaranteed that when working with small parts, you will drop at least one. This phenomenon is just how the universe works, there is no avoiding it. Digging though a carpet or dirty shop floor usually results in frustration and subsequent scrambling for a replacement part. Tired of crawling around on his knees looking for runaway parts, [Frank] decided to do something about it. He made a vacuum attachment that helps with the search… and it’s made from stuff he had kicking around the house.

The idea here is to suck up and contain the part without having it making it’s way into the vacuum. To do this there would have to be an intermediate chamber. For this, [Frank] used a multi-pack CD container. This was a great choice because it is clear, allowing him to see what enters the container, and it unscrews quickly making it easy to retrieve the tiny part. The inlet and outlet connectors are made from PVC and are attached to the CD container’s base with adhesive. To keep the debris from getting past the CD container, an old kitchen strainer was cut up and the screen material was used to only let air pass. Once a shop-vac is connected to the outlet pipe, the sucking can begin. [Frank] shows that he has to sift through a bunch of shop-floor crud to find his dropped screw, but it works!

The Greatest Thing Since (Toasted) Sliced Bread

June 9, 2015 by James Hobson 55 Comments

That’s right. [Colin Furze] just made a household appliance obsolete. Who needs a toaster when you can cut your bread… and toast it at the same time!

Leave it to [Furze] to make something out of the Hitchhiker’s Guide to the Galaxy a reality. Submitted as an idea by one of his subscribers to his new series called Furze’s Invention Show, he took it upon himself to make the long revered lightsaber bread knife. We were waiting for this day.

Unfortunately, it’s not exactly a light saber. In fact, its more of a light-saw-ber, which, pronounced with the right accent could be easily mistaken for the real deal. Using a re-wrapped microwave transformer — much like home-made spot welder rigs — [Furze] is pumping a ton of amps at low voltage through a hacksaw blade, making it red hot and ready to toast bread.

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Controlling A Rigol With Linux

June 6, 2015 by Brian Benchoff 19 Comments

The Rigol DS1052E is the de facto oscilloscope for any tinkerer’s bench. It’s cheap, it’s good enough, and it’s been around for a long time; with the new 1054 zed model out now, you might even be able to pick up a 1052E on the cheap.

[wd5gnr1] came up with a really interesting piece of software that allows a Linux system to control most of the functions on this popular scope. With just a USB cable, you can read and log all the measurement of the scope, save waveforms in CSV format, and send data to gnuplot and qtiplot.

Since the 1052E has been around for such a long time, there’s a bunch of software out there that takes advantage of the nifty USB port on the front of this scope. If you need a cheap spectrum analyzer, here ‘ya go, and tools for the .WFM files native to this scope even exist for Windows. [wd5gnr1] even says his tool can probably be ported to Windows, but ‘just use Linux.’