Impressive Sawdust Briquette Machine

January 16, 2023 by Anool Mahidharia 28 Comments

When you are a life long carpenter with an amazing workshop, you’re going to make a lot of saw dust, and managing its collection and storage poses quite a challenge. [Russ] from [New Yorkshire Workshop] built an impressive Briquette press to handle the problem.

It’s a hydraulic press that ingests saw dust and spits out compressed briquettes ready for fueling his rocket mass heater. The build starts with a batch of custom, laser cut steel parts received from Fractory. The heart of the machine is a 300 mm stroke hydraulic cylinder with a beefy 40 mm rod. The cylinder had to be taken apart so that the laser cut mounting flanges could be welded, slowly so as not to deform the cylinder. The intake feed tube was cut from a piece of 40 mm bore seamless tube. A window was cut in the feed tube and funnel parts were welded to this cutout. The feed tube assembly is then finished off with a pair of mounting flanges. The feed tube assembly is in turn welded to the main feed plate which will form the base of the saw dust container. The hydraulic cylinder assembly is mated to the feed tube assembly using a set of massive M10 high tensile class 10.9 threaded rods. The push rod is a length of 40 mm diameter mild steel bar stock, coupled to the hydraulic cylinder using a fabricated coupling clamp. On the coupling clamp, he welded another bracket on which a bolt can be screwed on. This bolt helps activate the limit switches that control the movement of the hydraulic cylinder and the feed motor. Continue reading “Impressive Sawdust Briquette Machine” →

Blinky Business Card Plays Snake And Connect Four

January 16, 2023 by Anool Mahidharia 6 Comments

There’s no better way to introduce yourself than handing over a blinky PCB business card and challenging the recipient to a game of Connect Four. And if [Dennis Kaandorp] turns up early for a meeting, he can keep himself busy playing the ever popular game of Snake on his PCB business card.

Quite wisely, [Dennis] kept his design simple, and avoided the temptation of feature creep. His requirements were to create a minimalist, credit card sized design, with his contact details printed on the silk legend, and some blinky LED’s.

The tallest component on such a design is usually the battery holder, and he could not find one that was low-profile and cheap. Drawing inspiration from The Art of Blinky Business Cards, he used the 0.8 mm thin PCB itself as the battery holder by means of flexible arms.

Connect-Four is a two player game similar to tic-tac-toe, but played on a grid seven columns across and six rows high. This meant using 42 dual-colour LED’s, which would require a large number of GPIO pins on the micro-controller. Using a clever combination of matrix and charlieplexing techniques, he was able to reduce the GPIO count down to 13 pins, while still managing to keep the track layout simple.

It also took him some extra effort to locate dual colour, red / green LED’s with a sufficiently low forward voltage drop that could work off the reduced output resulting from the use of charlieplexing. At the heart of the business card is an ATtiny1616 micro-controller that offers enough GPIO pins for the LED matrix as well as the four push button switches.

His first batch of prototypes have given him a good insight on the pricing and revealed several deficiencies that he can improve upon the next time around. [Dennis] has shared KiCad schematic and PCB layout files for anyone looking to get inspired to design their own PCB business cards.

Continue reading “Blinky Business Card Plays Snake And Connect Four” →

An ATX motherboard sits on a grey surface with the I/O in the foreground. Behind the I/O is a large image of Tux, the Linux penguin, taking up most of the PCB and winding its way around different components on the board. Tux is part of the PCB itself, with his feet, beak, and outline in gold, body in black silkscreen, and belly in green soldermask.

Designing Aesthetically-Pleasing PCBs

January 15, 2023 by Navarre Bartz 28 Comments

We’ve seen our share of custom PCBs here on Hackaday, but they aren’t always pretty. If you want to bring your PCB aesthetics up a notch, [Ian Dunn] has put together a guide for those wanting to get into PCB art.

There are plenty of tutorials about making a functional PCB, but finding information about PCB art can be more difficult. [Ian] walks us through the different materials available from PCB fabs and how the different layer features can affect the final aesthetic of a piece. For instance, while black and white solder mask are opaque, other colors are often translucent and affected by copper under the surface.

PCB design software can throw errors when adding decorative traces or components to a board that aren’t connected to any of the functional circuitry, so [Ian] discusses some of the tricks to avoid tripping up here. For that final artistic flair, component selection can make all the difference. The guide has recommendations on some of the most aesthetically pleasing types of components including how chips made in the USSR apparently have a little bit of extra panache.

If you want to see some more on PCB art, check out this work on full-color PCBs and learn the way of the PCB artist.

Make Your Own Pot And Encoder Knobs, Without Reinventing Them

January 14, 2023 by Donald Papp 10 Comments

Rotary potentiometers, switches, and encoders all share a basic design: adjustment is done via a shaft onto which a knob is attached, and knobs are sold separately. That doesn’t mean one knob fits all; there are actually a few different standards. But just because knobs are inexpensive and easily obtained doesn’t mean it’s not worth making your own.

A simple and effective indicator can be easily printed in a contrasting color.

Why bother 3D printing your own knobs instead of buying them? For one thing, making them means one can rest assured that every knob matches aesthetically. The ability to add custom or nonstandard markings are another bonus. Finally, there’s no need to re-invent the wheel, because [Tommy]’s guide to making your own knobs has it all figured out, with the OpenSCAD script to match.

By default, [Tommy]’s script will generate a knob with three shims (for interfacing to a splined shaft) when pot_knob(); is called. The number of shims can be adjusted by modifying potKnobDefaultShimCount. To give the knob a flat side (to interface with D-shafts), change flatted = false to flatted = true. And for adding a screw insert suitable for a set screw? Change tightenerDiameter = 0 from zero to the diameter desired.

The script is quite comprehensive and has sensible defaults, but it does require a bit of knowledge about OpenSCAD itself to use effectively. We have covered the basics of OpenSCAD in the past, and if you’re ready for a resource that will help you truly master it, here’s where to look.

Release Less Magic Smoke, With A Bulb Limiter

January 8, 2023 by Jenny List 29 Comments

As electronics have moved lower in voltage, it’s perhaps less common to work on live-mains equipment. Thus particularly among younger hardware hackers it sometimes seems as though such work is viewed as so dangerous as to be only for the foolhardy. In practice it remains safe, so long as appropriate precautions are taken and a few pieces of useful safety equipment are present. One of those mains bench essentials is something less common in 2022, a mains current limiter using a set of switched incandescent light bulbs. [Donna LaRocco] shares a modern take on the idea, incorporating a digital mains voltmeter.

The idea is that a mains device under test is connected in series with a light bulb of a suitable wattage to let through enough current to run the device in normal operation, but to light up and bring down the voltage if the device draws too much. It’s an extremely simple but effective tool. Traditionally these are built using household electrical fittings on a board, and this one is no exception. The voltmeter comes from the RV market where voltage drop is an issue, no doubt giving European readers a chance to chuckle with their 230 V outlets.

If mains safety needs your attention, it’s a subject we’ve addressed in the past.

A notated illustration showing how a mycelial network may be functionalized as a PCB substrate. The process starts with Cu vapor deposition onto the network followed by Au either by more vapor deposition or electrodeposition. Traces are then cut via laser ablation.

MycelioTronics: Biodegradable Electronics Substrates From Fungi

January 6, 2023 by Navarre Bartz 12 Comments

E-waste is one of the main unfortunate consequences of the widespread adoption of electronic devices, and there are various efforts to stem the flow of this pernicious trash. One new approach from researchers at the Johannes Kepler University in Austria is to replace the substrate in electronics with a material made from mycelium skins.

Maintaining performance of ICs and other electronic components in a device while making them biodegradable or recyclable has proved difficult so far. The substrate is the second largest contributor (~37% by weight) to the e-waste equation, so replacing it with a more biodegradable solution would still be a major step toward a circular economy.

To functionalize the mycelial network as a PCB substrate, the network is subjected to Physical Vapor Deposition of copper followed by deposition of gold either by more PVD or electrodeposition. Traces are then cut via laser ablation. The resulting substrate is flexible and can withstand over 2000 bending cycles, which may prove useful in flexible electronics applications.

If you’re looking for more fun with fungi, check out these mycelia bricks, this fungus sound absorber, or this mycellium-inspired mesh network.

KiCad 2022 End-of-Year Recap And 7.0 Preview

December 31, 2022 by Joseph Long 22 Comments

[Chris Gammell] moderated the KiCad 2022 End-of-Year Recap with several KiCad developers and librarians. They reviewed what’s been bubbling up in the nightly KiCad 6 builds, what we can expect from KiCad 7, and even answered some questions from the user community. Over the course of 2022, the KiCad project has grown both its development team and library team. The project even has a preliminary support commitment from the CERN Drawing Office!

Improvements to the KiCad Schematic Editor include smart wire dragging that simplifies moving components around within schematic diagrams. Components selected in the schematic now remain selected while switching to the PCB Editor. Internal documentation of schematics has advanced with support for fonts, embedded graphics, and the inclusion of hypertext links to datasheets and other reference materials. New features for PDF generation offer interactive files and links between sheets.

A new search panel within the KiCad PCB Editor supports finding components by footprint, net, or text search. A property panel allows common properties to be edited across multiple selected items. While a full-blown auto-router remains outside of the scope for KiCad, “push and shove” routing is faster and easier. An “attempt to finish” feature routes a quick connection for the currently selected trace, and “pack and move” positions all selected footprints into proximity to simplify placing them as neighbors within the board layout.

The KiCad PCB Editor also adds support for the use of fonts and inverted “knockout text” which even works on copper zones. Bitmap graphics can be imported and scaled beneath layout work as reference illustrations. Private footprint layers can be used to place extra documentation within footprints. The design rule checker (DRC) now can catch more layout issues, especially those that may impact manufacturability.

These are just a sampling of the impressive improvements we can expect with KiCad 7.0. There are also additions to circuit simulation and modeling features, a new command line interface for script-based automation, ARM64 support for KiCad running on Apple silicon, and a huge number of additions to the default library including symbols, footprints, and 3D Viewer models.

The KiCad team suggests several ways to support the project. There are always needs for additional developers and librarians. Financial contributions can be made at kicad.org. As users, we can run the nightly builds, try to break them, and give feedback in the form of detailed bug reports. Community testing will help make KiCad 7.0 as solid as possible. The project team is also seeking open hardware projects to include with KiCad 7.0 as demos. For example, the StickHub project was included with KiCad 6.0 as a demo.

The official release of KiCad 7.0 is currently scheduled for January 31, 2023. While we wait, let’s flashback to our January 2022 presentation of what features made it into the KiCad 6.0 release.

Continue reading “KiCad 2022 End-of-Year Recap And 7.0 Preview” →