The Othermill Is Something Else

I’ll admit. When I saw the Othermill for the first time I thought it was just another mill with cheap Chinese hardware inside sold as a premium. I’m ashamed to say that I even trash talked it a little bit. It gave me another chance to relearn that I should always do my research before being a jerk, check my assumptions thoroughly, and even then it’s not recommended. Other Machine Company was kind enough to let me swing by the office in Berkeley California. [Danielle], the CEO, led me through the design of the mill as well as the challenges in running the operation.

The Othermill is a serious machine, and with the recent release of the Othermill Pro, it’s only getting better. The components are not bargain basement. This is something that could be more obvious, but it’s almost entirely made from US sourced parts, including the custom stepper motors. There aren’t any ball bearings that will start to make strange noises in a year. It can now cut 6mil traces in a PCB all day long. To put it into perspective. The Othermill Pro costs a third of the price of an equivalent machine from LPKF and has the same capabilities.

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Books You Should Read: Instruments Of Amplification

Psst… Wanna make a canning jar diode? A tennis ball triode? How about a semiconductor transistor? Or do you just enjoy sitting back and following along an interesting narrative of something being made, while picking up a wealth of background, tips and sparking all sorts of ideas? In my case I wanted to make a cuprous oxide semiconductor diode and that lead me to H.P. Friedrichs’ wonderful book Instruments of Amplification. It includes such a huge collection of amplifier knowledge and is a delight to read thanks to a narrative style and frequent hands-on experiments.

Friedrichs first authored another very popular book, The Voice of the Crystal, about making crystal radios, and wanted to write a second one. For those not familiar with crystal radios, they’re fun to make radios that are powered solely by the incoming radio waves; there are no batteries. But that also means the volume is low.

Readers of that book suggested a good follow-up would be one about amplifier circuits, to amplify the crystal radio’s volume. However, there were already an abundance of such books. Friedrichs realized the best follow-up would be one on how to make the amplifying components from scratch, the “instruments of amplification”.  It would be unique and in the made-from-scratch spirit of crystal radios. The book, Instruments of Amplification was born.

The Experiments

Microphonic relays
Microphonic relays, via H.P. Friedrichs Homepage

The book includes just the right amount of a history, giving background on what an amplifier is and how they first came in the electrical world. Telegraph operators wanted to send signals over greater and greater distances and the solution was to use the mix of electronics and mechanics found in the telegraph relay. This is the springboard for his first project and narrative: the microphonic relay.

The microphonic relay example shown on the right places a speaker facing a microphone; the speaker is the input with the microphone amplifying the output. He uses a carbon microphone salvaged from an old telephone headset, housing everything in an enclosure of copper pipe caps, steel bar stock, nuts and bolts mounted on an elegant looking wood base. All the projects are made with simple parts, with care, and they end up looking great.

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Books You Should Read: The Car Hacker’s Handbook

I just had my car in for an inspection and an oil change. The garage I take my car to is generally okay, they’re more honest than a stealership, but they don’t cross all their t’s and dot all their lowercase j’s. A few days after I picked up my car, low and behold, I noticed the garage didn’t do a complete oil change. The oil life indicator wasn’t reset, which means every time I turn my car on, I’ll have to press a button to clear an ominous glowing warning on my dash.

For my car, resetting the oil life indicator is a simple fix – I just need to push the button on the dash until the oil life indicator starts to blink, release, then hold it again for ten seconds. I’m at least partially competent when it comes to tech and embedded systems, but even for me, resetting the oil life sensor in my car is a bit obtuse. For the majority of the population, I can easily see this being a reason to take a car back to the shop; the mechanic either didn’t know how to do it, or didn’t know how to use Google.

The two most technically complex things I own are my car and my computer, and there is much more information available on how to fix or modify any part of my computer. If I had a desire to modify my car so I could read the value of the tire pressure monitors, instead of only being notified when one of them is too low, there’s nowhere for me to turn.

2015 was the year of car hacks, ranging from hacking ECUs to pass California emissions control standards, Google and Tesla’s self-driving cars, to hacking infotainment systems to drive reporters off the road. The lessons learned from these hacks are a hodge-podge of forum threads, conference talks, and articles scattered around the web. While you’ll never find a single volume filled with how to exploit the computers in every make and model of automobile, there is space for a reference guide on how to go about this sort of car hacking.

I was given the opportunity to review The Car Hacker’s Handbook by Craig Smith (259p, No Starch Press). Is it a guide on how to plug a dongle into my car and clear the oil life monitor the hard way? No, but you wouldn’t want that anyway. Instead, it’s a much more informative tome on penetration testing and reverse engineering, using cars as the backdrop, not the focus.

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Evaluating the Unusual and Innovative Perf+ Protoboard

Back in 2015 [Ben Wang] attempted to re-invent the protoboard with the Perf+. Not long afterward, some improvements (more convenient hole size and better solder mask among others) yielded an updated version which I purchased. It’s an interesting concept and after making my first board with it here are my thoughts on what it does well, what it’s like to use, and what place it might have in a workshop.

Perf+ Overview

One side of a Perf+ 2 board. Each hole can selectively connect to bus next to it with a solder bridge. The bus strips are horizontal on the back side.
One side of a Perf+ board. Each hole can selectively connect to the bus next to it with a solder bridge. These bus strips are vertical. The ones on the back are horizontal.

The Perf+ is two-sided perfboard with a twist. In the image to the left, each column of individual holes has a bus running alongside. Each hole can selectively connect to its adjacent bus via a solder bridge. These bus traces are independent of each other and run vertically on the side shown, and horizontally on the back.

Each individual hole is therefore isolated by default but can be connected to one, both, or neither of the bus traces on either side of the board. Since these traces run vertically on one side and horizontally on the other, any hole on the board can be connected to any other hole on the board with as few as two solder bridges and without a single jumper wire.

It’s an innovative idea, but is it a reasonable replacement for perfboard or busboard? I found out by using it to assemble a simple prototype.

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Review: Monoprice MP Select Mini 3D Printer

2016 is the year of the consumer 3D printer. Yes, the hype over 3D printing has died down since 2012. There were too many 3D printers at Maker Faire three years ago. Nevertheless, sales of 3D printers have never been stronger, the industry is growing, and the low-end machines are getting very, very good.

Printers are also getting cheap. At CES last January, Monoprice, the same company you buy Ethernet and HDMI cables from, introduced a line of 3D printers that would be released this year. While the $300 resin-based printer has been canned, Monoprice has released their MP Select Mini 3D printer for $200. This printer appeared on Monoprice late last month.

My curiosity was worth more than $200, so Hackaday readers get a review of the MP Select Mini 3D printer. The bottom line? There are some problems with this printer, but nothing that wouldn’t be found in printers that cost three times as much. This is a game-changing machine, and proof 2016 is the year of the entry-level consumer 3D printer.

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Long-Term Review: Weller Magnastat Soldering Iron

One of the things you find yourself doing as a young engineer is equipping yourself with the tools of your trade. These will be the foundations upon which your career is built in a way that a diploma or degree certificate will never be, for the best degree in the world is less useful if the quality of your tools renders you unable to capitalise upon it. You may be lucky enough to make some of them yourself, but others you’ll lust after as unaffordable, then eventually put the boat out a little to buy at the limit of your meager income.

Your bench may have a few of these lifetime tools. They could be something as simple as screwdrivers or you may have one of those indestructible multimeters, but in my case my lifetime tool is my soldering iron. At some time in 1992 I spent about £60($173 back then), a lot of money for a student, on a mains-powered Weller Magnastat. The World Wide Web was still fairly fresh from Tim Berners-Lee’s NeXT in those days, so this meant a trip to my university’s RS trade counter and a moment poring over a telephone-book-sized catalogue before filling in an order slip.

The Magnastat is a simple but very effective fixed-temperature-controlled iron. The tip has a magnet on its rear end which holds closed a power switch for the heating element. When the tip has heated to the Curie temperature of the magnet, it loses its magnetism and the switch opens. The temperature falls to below the Curie temperature and the magnetism returns, the switch closes, the tip warms up again, and the cycle repeats itself. The temperature of the tip is thus dictated by the magnet’s Curie temperature, and Weller provides a range of tips fitted with magnets for different temperatures.

The result is an iron with enough power to solder heat-sucking jobs that would leave lesser irons gasping for juice, while also having the delicacy to solder tiny surface-mount components without destroying them or lifting tracks. It’s not a particularly small or lightweight iron if you are used to the featherlight pencil irons from today’s soldering stations, but neither is it too large or heavy to be unwieldy. In the nearly quarter century I have owned my Magnastat it has had a hand in almost everything I have made, from hi-fi and tube amplifiers through radio transmitters, stripline filters, kits, and too many repairs to mention. It has even been pressed into service plastic-welding a damaged motorcycle fairing. It has truly been a lifetime tool.

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BeagleBone Green, Now Wireless

Over the past few years, the BeagleBone ecosystem has grown from the original BeagleBone White, followed two years later by the BeagleBone Black. The Black was the killer board of the BeagleBone family, and for a time wasn’t available anywhere at any price. TI has been kind to the SoC used in the BeagleBone, leading to last year’s release of the BeagleBone Green, The robotics-focused BeagleBone Blue, and the very recent announcement of a BeagleBone on a chip. All these boards have about the same capabilities, targeted towards different use cases; the BeagleBone on a Chip is a single module that can be dropped into an Eagle schematic. The BeagleBone Green is meant to be the low-cost that plays nicely with Seeed Studio’s Grove connectors. They’re all variations on a theme, and until now, wireless hasn’t been a built-in option.

This weekend at Maker Faire, Seeed Studio is showing off their latest edition of the BeagleBone Green. It’s the BeagleBone Green Wireless, and includes 802.11 b/g/n, and Bluetooth 4.1 LE.

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