Table of contents for #71 in HackSpace

It’s been a tough couple of years to be a Raspberry Pi enthusiast and having to eke out your supply of boards, or search through online stores trying to find some for sale. Today, we firmly put that part of history behind us. The Raspberry Pi 5 is almost ready and if you’re a subscriber, we have reserved stock that you can pre-order (for recommended retail price). If you’re not a subscriber, don’t worry, there’s still time to subscribe and claim your spot at the front of the queue. To find out about the new release, we headed to Cambridge to get the inside story of the board from Eben Upton and James Adams. We found out about the shiny new SoC, the extra features and, of course, the power…

hsmag.cc/TouchCam You may have seen the Pi Cam by Mukesh Sankhla, an internet-connected Raspberry Pi-based camera capable of streaming video and images. This redesign takes that already nifty design and adds a couple of new features to make it even better. First and most obviously, there’s the touchscreen display, providing a visual interface for camera controls, image previews, and video playback. Mukesh has also added a 5V fan and heatsinks to provide efficient temperature regulation, and the whole thing is housed in an all-new 3D-printed housing designed in Fusion 360.…

There is a special kind of enjoyment that comes from making robots. Creating something that can interact with the real world, using parts you have built and code you have written, feels almost magical. Every robot offers its own challenges in mechanics, electronics, and computing that, when overcome, make the end result all that more rewarding. This is the reason for my ever-growing robot collection! L-Hex, a lidar-equipped hex (as in six) mecanum-wheeled robot, is the latest addition to my collection. It is triangular in shape, measuring 162mm in diameter and 120 mm tall. On each side are mirrored pairs of mecanum wheels for movement, driven by DC motors with encoders. Taking up a good portion of the robot’s height is a low-cost, 360-degree light detection and ranging (lidar) scanner,…

@concreted0g Jo Hinchliffe is a constant tinkerer and is passionate about all things DIY space. He loves designing and scratch-building both model and high-power rockets, and releases the designs and components as open-source. He also has a shed full of lathes and milling machines and CNC kit! In the last issue, we laid out our largest project so far – an RP2040 minimal layout example and, in the next issue, we want to add to this design. However, the schematic is already quite full and, if we’re not careful, the whole thing could become unmanageable. Let’s take a look at how we can keep things clean, tidy, and easy to work with. If you view last issue’s project (hsmag.cc/issue70), and jump into the Schematic Editor, it looks quite cramped (Figure…

@holtonhandmade Nicola King is a freelance writer and sub-editor. She tries her hand at most crafts, and a quick dabble in electronics has proved easier than she thought. Perhaps one of the most basic circuits you can create, a paper circuit is a low-voltage electronic circuit created on paper or cardboard, as opposed to on a PCB. The beauty of them lies predominantly in their simplicity, and the fact that you only need a few modest components in order to build one. Instead of wiring, you create a ‘trace’ using a conductive material as a substitute for the wires that would normally connect components on a breadboard or PCB. This simplicity makes paper circuits a fantastic way to either investigate circuits yourself, or to teach the fundamentals of electronic circuits…

MAKER Also known as Penguin Tutor. Maker and YouTuber that loves all things Raspberry Pi and Pico. Author of Learn Electronics with Raspberry Pi. penguintutor.com @stewartwatkiss Understand a way to expand your electronic circuits using I2C. Learn about how to interface with a port expander and see how this can be used for a large number of switches using a switch-array. The first circuit is based around an integrated circuit that you can build on a breadboard. Then, see how a similar technique is used for a 16-button, light-up keypad. Use the keypad to create a fun game of Mole Bop. 01 Using a port expanders Raspberry Pi Pico has 26 general-purpose input/output pins. For many projects that is more than enough, but sometimes we need more. For a 16-way keypad…

If you’re already familiar with FreeCAD, the Sketches tool can help you design linkages. It’s not really intended for this purpose, but it’s a 2D tool with an understanding of degrees of freedom and connections. To do this, first start a new project, then go to the Part Design workbench and create a new body, then a sketch. You can pick any plane for this. This sketch won’t directly lead to the final design – it just gives us a space to play with different setups and constraints. As an example, we’ll create a parallel movement four-bar linkage. The first thing you need to do is create four lines with their ends linked by coincident constraints. They should be roughly in a square, but we’ll set the exact lengths later.…

There are two types of twiddly knobs you can use with microcontrollers: potentiometers and rotary encoders. The former, which we've used here, create a changing voltage as they’re turned. This voltage can be read by an analogue input. They're easy to use and hold a physical memory of their position (i.e. if you power off the project, they will read the same value when you power it back on). However, they can only be turned a fixed amount. Rotary encoders emit a series of pulses as they’re turned, often with a soft click as they do. You can keep on turning them forever in either direction and they’ll keep on pulsing. They’re great for user interfaces (scroll wheels are one type of rotary encoder).…

@ben_everard Ben’s house is slowly being taken over by 3D printers. He plans to solve this by printing an extension, once he gets enough printers. Modern phones have famously abandoned the headphone jack, and it seems that there’s nothing us consumers can do about it. Like many people, this writer found himself in possession of several pairs of headphones that no longer work with his portable devices. And, like many people, he bought a small battery-powered Bluetooth receiver that plugs into the jack port on it. This kind of worked. It didn’t mount cleanly on the frame of the headphones (so he was planning a 3D-printed mount). However, after a couple of weeks, disaster struck and the battery stopped taking a charge. A sensible person would probably return this to…

If you don’t have a sublimation oven, you can create a printable surface on solid materials by using a hot laminating pouch. Lamination pouches are essentially a sheet of thin plastic with a transparent glue coating on the inside. If you split the pouch into two separate sides, you can hot-press the lamination plastic onto the glass, creating a plastic layer that you can sublimate onto. The result isn’t as resilient as using a sublimation spray, but you can get decent results from this technique, and it will work on most rigid materials. You can even get gloss and matte pouches, so you can choose the most appropriate surface finish for your product.…

Heat Transfer Vinyl (HTV) is a special type of vinyl that does exactly what its name implies. It’s a handy tool to have in your arsenal when working with stubborn materials like cotton, because it can perform a few handy functions. It will stick to natural fibres quite nicely, and act as an intermediate layer between the cotton and your printed design. It’s opaque, and white HTV can be used to block out an area on a coloured material to make coloured prints stand out. However, it does have a few drawbacks. It’s a relatively thick material that will completely cover most surface textures, so if you’re trying for a coarse canvas look, it’s probably not the best choice. It’s also very pliable, and any imperfections will imprint on it.…

@ben_everard SHAPER £109 shapertools.com The Shaper Trace is a drawing toolkit that converts sketches, or drawings, into scalable vector graphics (SVG) via a plastic frame and an app on your phone. The device is available for pre-order for £109, and is set to ship in December 2023. The key selling point of the Shaper Trace is its ability to swiftly convert hand-drawn sketches into vector graphics. By placing the Trace Frame over a drawing and using the Trace App, users get an SVG file, compatible with various maker tools like laser cutters, vinyl cutters, and CNC machines. You can use any pen or paper for the drawing, but you’ll get best results with a black pen on white paper. The Trace does come with a pen, but others will work…

Eben The Raspberry Pi 5 cost $25 million to make. And it’s composed out of three enormous engineering programmes (BCM2712, RP1, and the DA9091 PMIC), and it itself is an enormous engineering programme. That power supply is itself a vastly larger engineering programme than pretty much anything other than we’ve ever done, apart from Raspberry Pi 4. Raspberry Pi 4 was a few million dollars. It wasn’t cheap. But the Raspberry Pi 4 was probably a $5 million programme for us. HS And in terms of cost benefit, I guess, does that pay-off come from selling more units or making more profit per unit? Eben It comes from continuing to sell units. It’s a Red Queen’s race, against our competitors, and against the ever more demanding expectations of the public.…

Driving in any direction on a surface, known as omnidirectional motion, is a beneficial trait for robots needing to navigate complex environments or accurately position themselves to manipulate objects. One way to achieve this is to use a family of wheels known as omni wheels. Omni wheels are specially constructed wheels with many free-spinning rollers around their perimeters. These rollers let the wheels slide in their rolling direction, creating the effect of having practically zero surface friction in that direction. By arranging multiple wheels so that the driving directions of each overlap the rolling directions of the others, omnidirectional movement can be achieved. A typical omni wheel has its rollers angled at 90 degrees to the rotation axis of the wheel, making them slide sideways. This gives rise to two…

You can add images to schematics and, whilst you can place images anywhere on any page, a common use case for this is to add a company logo to the Title Block area. The Schematic Editor supports a wide range of image formats, including PNG, JPG, TIFF, BMP, and many more. Usefully, on import you can rescale the imported image. This is useful as you can import a larger, higher DPI image and then scale it down to fit the box. In the image, the dog logo has been created in Inkscape and exported as a PNG file with a transparent canvas. The image as exported is sized at around 700 × 500 pixels and has been exported at 300 dpi. This means that the image is good enough quality…

Obviously, we’ve used conductive copper tape here, but there are alternatives that can be used in paper circuits that might be worth trying out: • Conductive nylon fabric tape A clear advantage of this over copper tape is that it doesn’t crack when twisted, so traces won’t be broken as easily. Also, as it’s more flexible, you can use it on more flexible materials, such as felt, and you can sew through it. So, possibly an option to bear in mind for all those wearable/e-textile projects on your make list. One disadvantage, over copper tape, is that it can’t be soldered. hsmag.cc/ConductiveNylon • Conductive ink You can also purchase rollerball pens containing water-based, non-toxic conductive ink, and design your paper circuits using these. The lines that you draw will dry…

GET YOUR RASPBERRY PI 5 FIRST! Want to get Raspberry Pi 5 sent to you as soon as it’s released? With Priority Boarding, you can pre-order your Raspberry Pi 5 (4GB or 8GB) and it’ll be sent out in the first week. Raspberry Pi has set aside thousands of Raspberry Pi 5 computers for The MagPi and HackSpace magazine print subscribers to buy. Enough to guarantee every subscriber can get one without going out of stock. How it works! If you have a print subscription to HackSpace magazine or The MagPi, we will have your email on file. We’ll send each of our subscribers a unique code in the next few days. Take this to hsmag.cc/priorityboarding, where you can pre-order and pay for your Raspberry Pi 5. Get started New…

Generally, you want linkages to be stiff, and PLA is the stiffest common 3D printer filament. The only other significant consideration might be friction. If you need your linkage to keep running with minimal lost energy, then a material with a lower coefficient of friction, such as nylon, might be worth considering. It’s also possible to use some stock material to make the bars, and just 3D-print the hinges. Plastic, carbon fibre, and metal bar stock are all available, each with different properties, and it would be easy to 3D-print the joints between the bars to make the linkage.…

The code to control the original light was written using CircuitPython. However, at the time of writing, there are no Pico W Bluetooth libraries available for CircuitPython. Bluetooth connections are presently only supported by MicroPython. CircuitPython and MicroPython are very similar; they differ mainly in the availability of different libraries for specific devices. If you are serious about becoming an experienced embedded developer, you should aim to be familiar with both implementations. The author originally chose CircuitPython because of the availability of a library for the Pixie lamp he was using. However, he was able to convert this library to MicroPython and then use MicroPython for this project.…

You can sublimate onto transparent glass or ceramic in three ways: applying a Polycrylic or acrylic varnish; applying a vinyl sheet to the glass; or using a dedicated sublimation spray. The best results come from using a sublimation spray, but you’ll need a sublimation oven to cure the spray before you can apply a print to the surface. It’s also difficult to apply any form of coating onto glass without it settling unevenly, because glass is a very smooth material. To counteract this problem, you have two options: either use a dedicated adhesion promoter like Subli Glaze, or very lightly key the surface with abrasive paper (around 400 grit will suffice), then clean it with isopropyl alcohol. Taking an abrasive paper to a transparent material might seem crazy, but the…

@devinck It’s no secret that I love clocks, DIY electronic clock kits in particular. I’ve built at least a dozen of them over the years – most of them ended up being given as gifts that were always well-received. I’ve covered clock kits in the past, but it’s time to take a second look to see what’s new. Surprisingly, most of the big players in the DIY space haven’t added any more clock kits to their stores, but you can find a lot of new kits from independent and smaller-scale manufacturers. So, why do I like clock kits so much? It’s simple. Once completed, it’s one of those projects that you can keep enjoying for a long time. Many other kits are fun for a while, but most don’t have…

UUGEAR $26.43 pimoroni.com For some of you, the idea of a ready-made kit doesn’t sound like your idea of fun. You’re the more adventurous DIYer that wants to fully customise your build. Well, if that’s you, then the Witty Pi 4 Mini is the perfect starting point for your Raspberry Pi-based custom timekeeping build. This Witty Pi HAT features a real-time clock coupled with power management circuitry. If you are planning on a complex Raspberry Pi-based project that needs accurate time, and you want to run intermittently, and with very low power requirements, then this is the HAT for you. Check out the Pimoroni page for more on what you can make with the Witty Pi 4 Mini. VERDICT Witty Pi 4 Mini A great start for your own build.…

Now includes Scratch 3 projects! Inside: • Learn how to set up your Raspberry Pi, install an operating system, and start using it • Follow step-by-step guides to code your own animations and games, using both the Scratch 3 and Python languages • Create amazing projects by connecting electronic components to Raspberry Pi’s GPIO pins Plus much, much more! Just £10 Buy online: magpi.cc/BGbook…

@ben_everard INKSCAPE Free inkscape.org Inkscape is probably the most common vector drawing tool for makers. It’s one of those bits of software that spans multiple disciplines. We use it for laser cutting, plotting, CNC milling, PCB design, vinyl cutting, and 3D printing – we’ve even used Inkscape for embroidery. It is probably the most widely used piece of maker software. At a basic level, vector graphics are about lines. You join these lines together to make shapes, and these shapes might be anything – illustrators use them to create pictures, while makers might use them to define the cut routes of a laser, but to the software, they’re just lines. This is all opposed to raster graphics (which are the other main type of computer graphics). In raster graphics, you…

FREE Pico W for subscribers! GET SIX ISSUES FOR JUST: £30 UK / €43 EU / $43 USA & Canada GUARANTEED RASPBERRY PI 5 AVAILABLE AT LAUNCH for all subscribers SUBSCRIBER BENEFITS: > Get every issue of HackSpace magazine delivered to your door > Early access to the PDF edition > Beat the crowds with guaranteed Raspberry Pi 5 stock for subscribers > Get a free Raspberry Pi Pico W hsmag.cc/subscribe Subscribers will get a voucher giving them the chance to purchase one Raspberry Pi 5 from reserved stock at The Pi Hut (thepihut.com) for full retail price. Reserved stock means that these will be available even if they are out of stock for general purchase.…

A couple of months ago, I decided that I wanted to build an electric guitar. Since then, I’ve discovered that before you build an electric guitar, you first have to build the tools that you’ll use to build the guitar. I’m also finding that the one single most important measurement is the centreline. You can, and people have, installed guitar hardware onto toilet seats, machine guns, shovels, and loads of other objects, but without an accurate measurement of the centreline, it’s impossible to get a playable instrument. Electric guitars have steel strings which, when they’re tuned, exert a much stronger pull than the nylon strings found on classical guitars, so anyone making a guitar has to reinforce the guitar neck with a truss-rod. A truss-rod is an adjustable metal rod that…

Copper tape, sometimes known as ‘slug’ tape, is basically a thin strip of copper backed with adhesive. It’s popular thanks to its versatility and usefulness for a wide range of tasks, and it’s also broadly available from hardware stores and online. It’s available in either non-conductive or conductive forms. The conductive tape, as we’ve used here, can conduct electricity on both the top and bottom of the tape, which enables electrical connections to be made easily. Apart from being very helpful in creating paper circuits, here are a few other practical applications: • Wrapping and insulating wire circuits and electromagnetic shielding – copper tape is often used to shield electrical components from damaging electromagnetic interference, and is employed to protect a range of electrical equipment. • Slugs and snails, generally,…

@ben_everard Ben’s house is slowly being taken over by 3D printers. He plans to solve this by printing an extension, once he gets enough printers. Making a mechanism move is easy – you can add a motor or a handle to turn. However, making things move in the right way, if you don’t need simple spinning, is much harder. Converting between a relatively limited set of options for input movement and whatever particular motion your project needs requires thought, planning, and more often than not, a linkage. A linkage is a series of bars usually joined together by pivoting joints. By varying the lengths of the bars and the way they’re joined, we can create incredibly complex movements. Perhaps the most famous complex movement is Theo Jansen’s Strandbeest, which uses…

@robmiles Rob Miles has been playing with hardware and software since almost before there was hardware and software. You can find out more about his so-called life at robmiles.com. Recently, the author created a remote-controlled light based on an old camera flash he found for sale on a market stall. The light contains a Raspberry Pi Pico W programmed in CircuitPython that acts as a web server on a local network. The colour of the light is controlled via the web page hosted by the light. The Pico W also supports Bluetooth, and so in this project, a new version of the light is created which is controlled by a second Pico W-powered device sending Bluetooth commands. Continuing the upcycling theme of the previous article, this one uses an upcycled…

Dr Andrew Lewis is a specialist fabricator and maker, and is the owner of the Andrew Lewis Workshop. Sublimation printing works by heat-transferring coloured plastic onto plain plastic. But what happens when you need to transfer an image onto something that isn’t made from plastic? Commercial sublimation blanks are available for some items, but for others you’ll need to prepare the material you are working with so that an image will transfer properly. Cotton blends and purely synthetic fabrics are mostly suitable for sublimation printing without any extra preparation, but natural fibres like cotton aren’t. If you don’t have any other choice but to work with cotton, you can apply a fabric sublimation spray, or even just a clear acrylic spray paint to the area that you want to transfer…

Untreated wood is tricky to work with for sublimation for a few reasons. Wood isn’t usually pure white, and heating wood can release sticky resins that affect the colour of your image, completely blacking out some areas and staining others. Also, the texture of wood is uneven, and that can lead to wrinkling and poor adhesion in some cases. As an additional problem, materials like wood and cardboard are hygroscopic (absorb moisture), and that can give you issues even after you’ve printed your item. To prepare wood and thick cardboard for printing, press it for 10–15 minutes at 140°C to drive off any excess moisture, then let it cool. It should settle as a flat sheet. If it doesn’t, flip it over and give it another few minutes in the…

ICSTATION $12.31 tindie.com Despite the rather generic name, the DC 5 V Green LED Electronic Clock DIY Kit by ICStation is a perfect example of a kit that I love to use for teaching soldering. Even a beginner can easy solder this through-hole kit and, once complete, they have a fun and functional desktop clock. Even though it’s small and simple, it packs a bunch of features, including 12-hour and 24-hour time modes, an alarm, automatic brightness, and it even announces the time on the hour. An affordable clock kit that can speak the time? Fun! VERDICT DC 5 V Green LED Electronic Clock DIY Kit Affordable and simple to build. 9/10…

PLAY & CODE GAMES! ■ Set up Raspberry Pi for retro gaming ■ Emulate classic computers and consoles ■ Learn to code your own retro-style games ■ Build a console, handheld, and full-size arcade machine BUY ONLINE: magpi.cc/store…