Hackaday Links: May Day, 2016

Humble Bundle is a great way to fill up your Steam library – just pay what you want, and get some indie video games. The Humble Bundle is much more than video games, because No Starch Press just put up a bundle of books on hacking. No, there are no books about wearing balaclavas and using laptops with one hand. I haven’t written that book yet. There’s some choice books in this bundle, including [Bunnie]’s Hacking the XboxAutomate the Boring Stuff with Python, and Practical Malware Analysis.

The Raspberry Pi camera – the $25 add-on webcam that plugs directly into the Pi – is getting an upgrade. The original camera was a five Megapixel sensor that was EOL’d at the end of 2014. The Raspberry Pi foundation bought up a lot of stock, but eventually there would be a replacement. The new sensor is a Sony IMX219 eight Megapixel deal, available at the same price. We assume a NoIR version without the IR filter will be released shortly.

Here’s a little hardware review that doesn’t quite merit a full post. The Raspberry Pi Zero is great, and will be even better once production ramps up again and stock lands in warehouses. One problem with the Zero is the lack of USB ports, leading to at least two Hackaday posts with the exact same headline, ‘Yet Another Pi Zero USB Hub‘. Obviously, there’s a market for an easy to use USB hub for the Zero, and this company is stepping up to fill the need. The killer feature here is the use of pogo pins to tap into the USB differential lines, power and ground pads on the bottom of the Pi Zero. The USB hub is based on the popular FE 1.1 4-port USB hub controller, giving the Pi Zero four USB 2.0 ports. Does it work? Yeah, and it’s only $10. A pretty neat little device that will be very useful when Pi Zeros flood workbenches the world over.

It was announced in 2014, released in 2015, but the STM32F7 hasn’t seen a lot of action around these parts. A shame, because this is the upgrade to the famously powerful STM32F4 microcontroller that’s already capable of driving high-resolution displays through VGA, being an engine control unit for a 96 Ford Aspire, and being a very complex brushless motor driver. The STM32F7 can do all of these and more, and now ST is cutting prices on the F7’s Discovery Board. If you’re looking for a high-power ARM micro and don’t need to run Linux, you won’t do better elsewhere.

Need to reflow a board, but don’t have a toaster oven? Use a blowtorch! By holding a MAPP blowtorch a foot away from a board, [whitequark] was able to successfully reflow a large buck converter. There’s a lot of water vapor that will condense on the board, so a good cleaning afterward is a good idea.

A few weeks ago, [Mr. LeMieux] built a 360 degree, all-metal hinge. He’s been up to something a little more dangerous since then: building piles of mini table saws. Small table saws are useful for miniatures, models, and the like. [Mr. LeMieux]’s table saw is a piece of CNC’d aluminum, with a bearing and saw arbor that attaches to an electric drill. Dangerous, you say? Not compared to the competition. Behold the worst forty dollars I’ve ever spent. This Horror Freight mini table saw is by far the worst tool I’ve ever used. The bed was caked with streaky layers of paint, uneven, the blade wasn’t set at 90 degrees, and the whole thing was horrifically underpowered. Trust me when I say the CNC electric drill version is safer.

Engineering Meets Craftsmanship in this Guitar Fretting Jig

178-440Cutting the slots in a guitar’s neck for the frets requires special tooling, and [Gord]’s contribution to his friend’s recent dive into lutherie was this lovingly engineered and crafted fret mitering jig. We’d love to have a friend like [Gord].

We’ve covered a number of [Gord]’s builds before, and craftsmanship is the first thing that comes to mind whether the project is a man-cave clock or artisanal soaps. For this build, he stepped up the quality a notch – after all, if you’re going to build something you could buy for less than $200, you might as well make it a thing to behold.

There’s plenty to feast the eyes on here – an oak bed with custom logo, the aluminum jig body with brass accents, and the precision bearings that guide the pricey backsaw. Functionality abounds too – everything is adjustable, from the depth of cut to the width of the saw blade. There’s even a place to store the adjustment tool.

The result? Well, let’s just say that [Gord] and his friend [Fabrizio] are kindred spirits in the craftsmanship department. And [Fab]’s not a bad axeman either, as the video below shows.

Continue reading “Engineering Meets Craftsmanship in this Guitar Fretting Jig”

Hand Drill To Band Saw Conversion

Need a band saw but only have a drill kicking around? That may not be a common problem but if you ever run into it, [Izzy] has got you covered. He’s on a mission to make a drill-powered workshop and in his YouTube video, he shows a small bench top band saw he made that is powered by a corded hand drill.

The main frame is made from doubled up 3/4″ plywood. The saw blade is strung between two wooden wheels. Those wheels have tape applied to their outer diameter to create a crowned roller. That crown keeps the saw blade tracking in the middle of the wheel. The bottom wheel is mounted to an axle that is supported by bearings in the main frame. That axle pokes out the back and is connected to the drill. The top wheel has integrated bearings and ride on a stud mounted to the frame. The blade seems to be pretty tight although there is no noticeable tensioning system.

The video shows that this DIY band saw can cut through 1.5 inch wood fairly easily. Even so, there are clearly some needed features, like guide bearings for the blade and an overall cover to prevent accidental lacerations. But we suppose, even professional saws can be dangerous if not treated with respect.

Smarter-than-wood Saw Blade Makes Perfect Foldable Joints

[Andrew Klein] knows the pain of building drawers from plywood. It can be a pain to get all of the pieces measured and cut just right. Then you have to line them up, glue them together, and clamp them perfectly. It’s time-consuming and frustrating. Then one day it hit him that he might be able to make the whole process much easier using a custom saw blade.

The the video below, [Andrew] does a great job explaining how the concept works using a piece of paper. The trick is that the plywood must be cut in a very specific shape. This shape results in the plywood just barely being held together, almost as if it’s hinged. The resulting groove can then be filled with wood glue, and the plywood is folded over on itself. This folding process leaves no gaps in the wood and results in a strong joint. Luckily this special shape can be cut with a specialized saw blade.

This new process removes the requirement of having five separate pieces for a drawer. Instead, only four cuts are needed on a single piece of square plywood. The corners are then removed with a razor blade and all four sides are folded up and into place. [Andrew] shows that his prototype blade needs a little bit of work, but he’s so hopeful that this new invention will be useful to others. Continue reading “Smarter-than-wood Saw Blade Makes Perfect Foldable Joints”

Table Saw Kickback Video Ends Badly

Our comments section has been pretty busy lately with talk of table saws and safety, so we decided to feature this sobering video about table saw kickback. [Tom] is a popular YouTube woodworker. He decided to do a safety video by demonstrating table saw kickback. If you haven’t guessed, [Tom] is an idiot – and he’ll tell you that himself before the video is over. There are two hacks here. One is [Tom’s] careful analysis and preparation for demonstrating kickback (which should be fail of the week fodder). The other “hack” here is the one that came breathtakingly close to happening – [Tom’s] fingers.

Kickback is one of the most common table saw accidents. The type of kickback [Tom] was attempting to demonstrate is when a board turns and catches the blade past the axle. On a table saw kickback is extremely dangerous for two reasons. First, the piece of wood being cut becomes a missile launched right back at the saw operator. We’ve seen internal injuries caused by people being hit by pieces of wood like this. Second, the saw operator’s hand, which had just been pushing the wood, is now free to slid right into the blade. This is where a SawStop style system, while expensive, can save the day.

The average 10 inch table saw blade has an edge traveling at around 103 mph, or 166 kmh. As [Tom] demonstrates in his video, it’s just not possible for a person to react fast enough to avoid injury. Please, both personal users and hackerspaces, understand general safety with all the tools you’re using, and use proper safety equipment. As for [Tom], he’s learned his lesson, and is now using a SawStop Table.

Continue reading “Table Saw Kickback Video Ends Badly”

Fixing tools with 3D printers


Over at the Manchester Hackerspace, [Bob] has been busy getting a 30-year-old bandsaw up and running. The saw worked great, but it was missing a fence, making straight cuts difficult to say the least.  The solution, of course, was to build a new fence, and [Bob] decided to capitalize on his hackerspace’s workshop by making a new fence with a 3d printer.

[Bob] began by taking careful measurements of the saw’s table and the channel running down the length of it. These measurements were plugged into OpenSCAD, and after a few iterations, [Bob] had an extremely well-fitting profile a fence could be attached to.

With the profile down, [Bob] created a new part in OpenSCAD that would hold an aluminum angle piece. This was attached to the plastic parts with screws, and the entire assembly clamps down to the saw with the help of a few 5mm bolts. For a machine that is usually dedicated to making 3D printer parts and Yoda heads, [Bob] did a great job making good use of his 3D printer.

A table saw to cut solar panels


Steampunker extraordinaire [Jake von Slatt] loves the idea of solar-powered garden lights soaking up the sun’s rays during the day and powering a LED in the evening. Commercially available solar lanterns, as [Jake], you, me, and everyone else on the planet have discovered, are universally terrible and either don’t have solar panels large enough to charge a battery, or only last a year or so. [Jake]’s solution was to make his own solar lanterns and in the process he came up with a great way of cutting his own solar panels.

[Jake] turned to ebay to source 100 3″ x 6″ solar panels for about $30. These are broken panels, factory rejects, but still are able to produce the 0.5 Volts they should. Since these are rather large panels for a solar lantern, [Jake] needed a way to cut these panels into manageable sizes.

To cut the panels, [Jake] made a box to fit a Dremel with a right angle attachment and a port for a vacuum cleaner. There’s a sled for the panels with markings at 40, 80, 75, and 150 mm so the panels can be quickly cut to size with a diamond cutting wheel.

After the boards are cut, [Jake] checks them out with a multimeter to be sure they’re producing the half volt they should. After that, it’s a simple matter of soldering them together and adding them to his solar lanterns.