Breathe Easy with a Laser Cutter Air Filter

A laser cutter is a great tool to have in the shop, but like other CNC machines it can make a lousy neighbor. Vaporizing your stock means you end up breathing stuff you might rather not. If you’re going to be around these fumes all day, you’ll want good fume extraction, and you might just consider a DIY fume and particulate filter to polish the exhausted air.

15203365_644939182347358_619032134291602214_nWhile there’s no build log per se, [ZbLab]’s Facebook page has a gallery of photos that show the design and build in enough detail to get the gist. The main element of the filter is 25 kg of activated charcoal to trap the volatile organic compounds in the laser exhaust. The charcoal is packed into an IKEA garbage can around a prefilter made from a canister-style automotive air cleaner – [ZbLab] uses a Filtron filter that crosses to the more commonly available Fram CA3281. Another air cleaner element (Fram CA3333) makes sure no loose charcoal dust is expelled from the filter. The frame is built of birch ply and the plumbing is simple PVC. With a 125mm inlet it looks like this filter can really breathe, and it would easily scale up or down in size according to your needs.

No laser cutter in your shop to justify this filter, you say? Why not build one? Or, if you do any soldering, this downdraft fume extractor is a good way to clear the air.

Daisy Kite Wind Turbine: Now You Can Buy One

The Isle of Lewis is the largest of the Scottish Outer Hebrides, sitting in the North Atlantic off the west coast of the Scottish mainland. It is the first landfall after thousands of miles of ocean for a continuous stream of Atlantic weather systems, so as you might imagine it is a place in which there is no shortage of wind.

It is thus the perfect situation for a wind power startup, and in the aptly-named Windswept and Interesting Ltd it has one that is pushing the boundaries. Their speciality is the generation of power from spinning kites, arrays of kites that transmit power to a ground-based generator through the rotation of their lines, and because they release their designs as open source they are of extra interest to us.

Of course, if you are a seasoned reader you’ll now be complaining that we’ve covered this story before when they had an entry in the 2014 Hackaday Prize, so what’s new? The answer is that the 2014 story was a much earlier iteration than their current multi-level kite array, and that they have now reached the point of bringing their products to market. You can buy one of their prototypes right now, and there is a soon-to-be-launched crowdfunding campaign for their latest model. It’s not exactly cheap, but this first product is the result of 5 years of product development, and it is pretty obvious that more is on the way. For any open hardware startup to stay afloat that long is an impressive achievement, to do so in a field in which you are not surrounded by a huge supporting industry in the way for example electronics startups are is nothing short of amazing.

If you would like to have a go at building one of their spinning kites, you can do so with full instructions released under a Creative Commons licence, but for non kite builders their website is a fascinating read in its own right. Their YouTube channel  in particular has a wealth of videos of previous tests as well as design iterations, and is one on which many readers will linger for a while. Below the break we’ve put one of their most recent, a montage showing the kite evolution over the years.

Continue reading “Daisy Kite Wind Turbine: Now You Can Buy One”

A Portable, Accurate, Low-Cost, Open Source Air Particle Counter

If you live in a city with poor air quality you may be aware that particulates are one of the chief contributors to the problem. Tiny particles of soot from combustion, less than 10μm across, hence commonly referred to as PM10. These are hazardous because they can accumulate deep in the lungs, wherein all kinds of nasties can be caused.

There are commercial sensors available to detect and quantify these particles, but they are neither inexpensive nor open source. [Rundong] tells us about a project that aims to change that situation, the MyPart, which is described as a portable, accurate, low-cost, open source air particle counter. There is a GitHub repository for the project as well as a series of Instructables covering the build in detail. It comes from a team of members of the Hybrid Ecologies Lab at UC Berkeley, USA.

Along the way, they provide a fascinating description of how a particulate sensor works. A laser shines at right angles across a photodiode, and is brought to a focal point above it. Any particulates in the air will scatter light in the direction of the photodiode, which can thus detect them. The design of a successful such sensor requires a completely light-proof chamber carefully built to ensure a laminar flow of air past laser and diode. To that end, their chamber has several layers and is machined rather than 3D-printed for internal smoothness.

We’ve covered quite a few environmental sensors over the years here at Hackaday. An open source volatile organic compound (VOC) detector featured last year for example, or this Raspberry Pi-based  system using a commercial gas sensor.

Fail of the Week: Upcycling Failed 3D Prints

Is it possible to recycle failed 3D prints? As it turns out, it is — as long as your definition of “recycle” is somewhat flexible. After all, the world only needs so many coasters.

To be fair, [Devin]’s experiment is more about the upcycling side of the recycling equation, but it was certainly worth undertaking. 3D printing has hardly been reduced to practice, and anyone who spends any time printing knows that it’s easy to mess up. [Devin]’s process starts when the colorful contents of a bin full of failed prints are crushed with a hammer. Spread out onto a properly prepared (and never to be used again for cookies) baking sheet and cooked in the oven at low heat, the plastic chunks slowly melt into a thin, even sheet.

[Devin]’s goal was to cast them into a usable object, so he tried to make a bowl. He tried reheating discs of the material using an inverted metal bowl as a form but he found that the plastic didn’t soften evenly, resulting in Dali-esque bowls with thin spots and holes. He then flipped the bowl and tried to let the material sag into the form; that worked a little better but it still wasn’t the win he was looking for.

In the end, all [Devin] really ended up with is some objets d’art and a couple of leaky bowls. What else could he have done with the plastic? Would he have been better off vacuum forming the bowls or perhaps even pressure forming them? Or does the upcycling make no sense when you can theoretically make your own filament? Let us know in the comments how you would improve this process.

Continue reading “Fail of the Week: Upcycling Failed 3D Prints”

Living off the Grid, on Water Power

When you think of living off the grid, you often think of solar power. But if you’ve got a good head, and enough flow, water power can provide a much more consistent flow of electrons. All it requires is a little bit of engineering, epic amounts of manual labor, and some tricks of the trade, and you’ll have your own miniature hydroelectric power plant.

[Homo Ludens], the playful ape, has what looks like a fantastic self-sufficient home/cabin in a beautiful part of Chile. His webpages are a tremendous diary of DIY, but the microhydro plant stands out.

You might expect that building a hydro plant involves a lot of piping, and trenching to lie that pipe in, but the exact extent, documented in many photos, is sobering. At places, the pipe needed to be bent, and [Homo Ludens] built a wire-mesh pipe heater to facilitate the work — with the help of a few friends to weigh the pipe down at either end and create the bend. The self-wound power transformer is also a beauty.

There’s a lot more detail here than we can possibly get into, so go check it out. And if you’re in the mood for more hydro, we’ve recently run a writeup of a less ambitious, but still tidy, project that you should see. Or you could just rip apart an old washing machine.

Thanks [Patrick] for the great tip!

A Modest But Well-Assembled Home Hydropower Setup

We have all opened an electricity bill and had thoughts of saving a bit of money by generating our own power. Most of us never get any further than just thinking about it, but for anyone willing to give it a try we are very fortunate in that we live in a time at which technology has delivered many new components that make it a much more straightforward prospect than it used to be. Electronic inverters, efficient alternators, and electronic battery management systems are all easy to find via the internet, and are thus only a matter of waiting for the courier to arrive.

Pelton Wheel
Pelton Wheel

[Frédéric Waltzing] is lucky enough to have access to a 135 foot (38 metre) head of water that those of us in flatter environments could only dream of. He’s used it to generate his own power using a modestly sized but very effective turbine, and he documented it in a Youtube video which you can see below the break.

He brings the water to his turbine house through a 1.5 inch plastic pipe, in which he maintains a 55PSI closed pressure that drops to 37PSI when the system is running. His Pelton wheel develops 835RPM, from which a small permanent magnet alternator provides 6.3A for his battery management system. An Enerwatt 2KW inverter provides useful power from the system.

This hydroelectric installation might not be very large, but its key is not in its size but that it can run continuously. A continuous free 6.3A charge can store up a lot of energy for those times when you need it.

Continue reading “A Modest But Well-Assembled Home Hydropower Setup”

Finding A Use For Surplus Filament Spools

If you’re a heavy user of a 3D printer, or a welder, you’ll know the problem of empty spools. You’ve used up all the filament or the welding wire, and you’re left with a substantial plastic spool. It’s got to be useful for something, you think, and thus it’s Too Good To Throw Away. Before you know it you have a huge pile of the things all looking for a use that you know one day you’ll find.

If you follow the example of [Chuck Hellebuyck], you could use them as wheels for a small go-kart (YouTube link). He 3D-printed some hub adapters for the spools to use skate bearings, mounted them of threaded axles to a classic wooden go-kart frame, and set off downhill wearing his stock-car racing helmet.

Of course, [Chuck]’s go-kart is a bit of fun, but it’s probably fair to say that 3D printer spools are not the ideal wheel. Those rims aren’t particularly durable, and with no tires he’s in for a bumpy ride. Perhaps a tire could be found to fit and a tube placed within it, but that would start to sound expensive against those cheap off-the-shelf wheelbarrow items.

But the project does raise the interesting question: what exactly do you do with your empty spools? There have to be some awesome uses for them, so please share yours in the comments. Meanwhile follow Chuck’s go-kart adventures in the video below the break.

Continue reading “Finding A Use For Surplus Filament Spools”