Extending EagleCAD With Python

June 30, 2014 by Brian Benchoff 45 Comments

eagle Although it’s derided for not being open source, EagleCAD is an extremely popular piece of schematic and PCB layout software. Most of the popularity is probably due to the incredible amount of part libraries – it’s certainly not the features Eagle has to offer or its horrible scripting capabilities. [Rob] had enough of the lack of good scripting support in Eagle, so he’s been spending his time making Eagle’s ULP work with Python. He’s only been at it a short time, but already it’s much more usable than the usual Eagle scripts.

Below you can check out a pair of videos of [Rob]’s Python tools for Eagle in action. The first video goes through aligning a few symbols and creating a board outline (with proper curves!) from a DXF file. The second video shows exactly how valuable these tools are when laying out a board: imagine hundreds of LEDs and resistors automatically aligned to each other with a single click of a mouse. Beautiful.

All the PyEagle stuff is available on [Rob]’s github, with a DXF importer, group manager, and alignment tool included. Now that everything’s Python, it’s easy to build your own tools without relying on Eagle’s odd ULP language.

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Pimp My Cutting Fluid Pot

June 26, 2014 by Kristina Panos 16 Comments

oil pot

Think about the simple tools you use every day. From writing implements to wire spoolers, there is arguably nothing that deserves to be hot rodded more than the things you depend on and might even take for granted.

For mad machinist [Chris], one of those everyday tools is his cutting fluid pot. Of course he already had one. A heavy one. A manly one. But it wasn’t completely ideal, and it wasn’t plated with gold that he prospected, refined, and processed himself. More on that in a minute.

[Chris] had obtained some neodymium ring magnets a while back. He was playing around with them in his shop when he noticed that his cutting fluid applicator brush fit nicely through the center and, being metal, was contained nicely through the wonders of magnetism. It was then that he decided to build a cutting fluid pot that would keep his brush in place and remain upright. Better living through magnetism.

He drilled and chamfered the brush hole out of a #20 JIC hydraulic cap and used the matching plug for the base. In case your catalog is out of reach, those are a 1¼” pair. [Chris] bored tiny pockets in the base for tiny magnets. After bathing both parts in delicious brake cleaner, he adhered all the magnets with LOCTITE®.

Okay, so, he’s done, right? No. Of course not. It did not surprise us to learn that [Chris] is also a miner, and not the 8-bit kind that hates creepers. Over the last two years, he prospected, refined, and other gold-related verbs using equipment he made himself. Just make the jump and watch the video before we give it all away. You’ll laugh, you’ll cry, you’ll be compelled to watch his other videos.

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Bluetooth Security And Capacitive Sensing Tool Cabinet Handles

June 25, 2014 by James Hobson 13 Comments

Locking tool cabinet

[Andy] needed a new set of locks for his tool cabinets at work, but not wanting to carry around another key (or to remember a combination!) he decided to throw this little hack together — solenoid locking, capacitive sensing, tool cabinet door handles.

To do this he’s using a Bluetooth low energy breakout board coupled with an Arduino, two solenoid locks, and two capacitive sensors. He’s modified a pre-existing iPhone app to control the system, dubbed: The BlueLock Control.

When [Andy] is present with his phone, the system can be activated, allowing for automatic unlocking the moment you touch the metal handle. Usually he leaves it unlocked for the majority of the work day, but as soon as the day is done it’s just a simple swipe on his phone to engage lock mode for the night. And just in case he’s also added manual push-buttons for both solenoids in case anything goes wrong with the capacitive sensors. Cool hack [Andy!]

While you’re at it, why not make a keyless entry system for your car using Bluetooth too?

The State-Based Nixie Multimeter

June 24, 2014 by Brian Benchoff 29 Comments

state

Instead of numbers the IN-15A Nixie tube has symbols, specifically n, μ, P, -, +, m, M, k, Π, and %. The related IN-15B Nixie has letters: A, F, H, Hz, Ω, S, V, and W. These should look familiar to you. [kittan] decided it would be really cool to have a Nixie-equipped multimeter, and since he’s going retro fabulous anyway, he might as well make his multimeter controllerless, with discrete logic and comparator ICs. It’s a state-based Nixie multimeter, and it’s going to be freakin’ awesome.

The basic plan of the multimeter is a precision 1V voltage reference, a bunch of opamps, and a ton of resistors to form a ladder All the opamps in each decade are XOR’d together, so when one of the ten comparators for each decade stage is tripped, only one number will display on the (numeric) Nixie tube.

With a reasonable plan for measuring a voltage, it’s not too hard to expand the design for other measurements. V=IR, so with a constant current, V=R. The same equation can be used with a fixed resistance to determine current. Capacitance can be measured by comparing the change in charge of a known capacitor. Inductance, conductance, power, and frequency are all planned for this monster of a multimeter.

The initial PCB design is completed (and shown above) and it’s theoretically possible to do on a single-sided board with a minimum of jumpers. An amazing project, and even though you could probably find a similar, ancient meter in a trash heap or on a collector’s shelf, this is by far one of the best Nixie projects we’ve ever seen.

Wooden Band Saw Fears Its Wood-Cutting Brethren

June 22, 2014 by Rich Bremer 18 Comments

DIY Wooden Bandsaw

What is cooler than building a band saw out of wood? Building two, of course! And that is exactly what [Pekka] did. The first was a small bench top model while the second was a much larger version with the saw blade strung between big 13-3/4 inch wheels. For those who are unfamiliar with band saws, they are tools that have a long thin blade that is routed around rotating wheels. The wheels are spread apart to make the blade taut. Unlike the reciprocating action of a jigsaw, saws-all or scroll saw, the band saw blade continually rotates in one direction. These blades are typically thin making it easy to cut irregular and curved shapes.

The frame of [Pekka’s] larger machine is made from 35mm (~1-3/8″) plywood. This proved to be a sturdy frame material. The previously mentioned wheels were made by gluing pieces of oak together, mounting the assembly on a wood lathe and turning the outer diameter down to size. By using multiple piece of wood to construct the wheels allows the grain direction of each portion to be parallel with the blade. This method of construction ensures any expansion/contraction of the wood is uniform around the wheel. A strip of rubber around the blade’s outer diameter provides the friction required to prevent the blade from slipping.

[Pekka’s] friend was nice enough to turn the flanged axle shafts on his metal lathe. These shafts support the wooded wheels and are mounted in pillow block bearings. The upper pillow blocks are mounted to a sliding support that allows adjusting the tension of the saw blade. [Pekka] was not going to be satisfied with a one-speed band saw so he grabbed a motor he had kicking around that originally came from a wood lathe and already had 4 different sized pulleys mounted on the shaft.

This is a great project that shows what can be done with a little desire and ingenuity.

Clever Re-purposing Of A Power Drill Results In A Mini Wood Lathe

June 19, 2014 by James Hobson 25 Comments

Power Drill Wood Lathe

Ever use a lathe? No? Neither had [Jack Hauweling], but that didn’t stop him from building his own and learning how!

Lathes are a lot of fun, especially for small wood working projects. Using mostly wood and a few small pieces of hardware, [Jack] was able to build one in an afternoon that works quite well!

He’s using a cheap corded power drill to drive the work piece, but what we really like is how he made the spur center and spur live center out of a few pieces of threaded rod and a standoff. It’s a simple system that lets him secure the work piece fairly easily simply by tightening the threaded shaft of the live center.

In the video after the break he goes through the entire build process and even shows off his first attempts at using the lathe — he actually was able to make a very nice tool grip on his third try!

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The Analog Swiss Army Knife

June 19, 2014 by Brian Benchoff 33 Comments

11300

While FPGAs get all the credit for being the hip new thing, they are inherently digital devices. Without a proper ADC and DAC, you won’t be delving into the analog domain with your programmable logic. Maxim has just put out a chip that does just that: an analog swiss army knife with 20 pins that are configurable as analog to digital converter, digital to analog converters, GPIO, or any mix of the above.

The MAX11300 includes twenty IO ports, each capable of becoming an ADC, DAC, or GPIO, with pairs of ports capable of being configured as a logic level translator or an analog switch. The ADCs and DACs are 12-bit, with input and output ranges from -10V to +10V.

As a nice little bonus, the chip is controlled over SPI, making this an interesting device for a small “do anything analog” tool we’re sure will hit Tindie or Seeed Studio before the year is out. Luckily for whoever would create such a device, Maxim has a nice GUI for configuring each of the 20 pins on their chip, Of course Maxim already offers an evaluation kit for the MAX11300. It’s $100 USD and is Windows only.

The MAX11300 is available in either 40-pin TQFN or 48-pin TQFP packages (with the larger, easier to solder TQFP shipping later) for about $5.80 USD in quantity 1000, or $11.37 in quantity one.Video below showing off the MAX11300 reading and writing analog values to a few pins, and a good look at the configuration software.

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