Let’s be honest. When it comes to operating miter saws, these tools kick dust out the back like a spray paint can. Most of us have accepted this quirk as-is, but not [Inspire Woodcraft] who’s on a mission to achieve near perfect dust collection. And he nearly has it. With a budget dust collection setup, he’s able to eliminate over 90% of the dust from his cuts, and others who’ve adopted his setup can vouch for his results.

The solution comes in two pieces. First, he focuses on creating a new dust shroud or “boot” for collecting dust through the vacuum hookup on the back of the saw. What’s key here is that this dust boot is made from squishy silicone, enabling it to flare outwards and spread out as the saw travels downward into the material. It’s clear that [Inspire Woodcraft] has gone through dozens of material and shape iterations, but the result is sturdy enough to stay open with the vacuum running through the back hose attachment.

With the dust nearly perfectly funneled from the back, the second tweak focuses on rerouting stray dust away from the table and directly into this boot. [Inspire Woodcraft] later noticed that dust collection from the bottom of his miter saw simply didn’t exist, so dust would accumulate at his feet.

His solution? To create a second shroud that fits under the throat plate that takes sawdust once destined for the ground and ejects it backwards and straight into the dust collection boot.

Altogether, this setup solves a long-existing problem with a handful of commodity parts and a few 3D prints. [Inspire Woodcraft] has also chronicled his journey in such detail where you too could recreate his solution from the video. But if you’re feeling lazy, and you’re lucky enough to own the same Dewalt DW716 or DWS716 model miter saws, you can simply snag a kit from his website.

If all this talk of miter saws has your reaching for a screwdriver to see what modified mayhem you can unleash with yours, look no further than this LED hack that adds a shadow line to your cuts.

Over the years, I’ve been curious to dig deeper into the world of the manufacturing in China. But what I’ve found is that Western anecdotes often felt surface-level, distanced, literally and figuratively from the people living there. Like many hackers in the west, the allure of low-volume custom PCBs and mechanical prototypes has me enchanted. But the appeal of these places for their low costs and quick turnarounds makes me wonder: how is this possible? So I’m left wondering: who are the people and the forces at play that, combined, make the gears turn?

Enter Prototype Nation: China and the Contested Promise of Innovation, by Silvia Lindtner. Published in 2020, this book is the hallmark of ten years of research, five of which the author spent in Shenzhen recording field notes, conducting interviews, and participating in the startup and prototyping scene that the city offers.

This book digs deep into the forces at play, unraveling threads between politics, culture, and ripe circumstances to position China as a rising figure in global manufacturing. This book is a must-read for the manufacturing history we just lived through in the last decade and the intermingling relationship of the maker movement between the west and east.

From Copy to Prototype

Lindtner does a spectacular job detailing why Chinese manufacturers will readily duplicate and resell existing designs. The answer is multi-faceted but involves, in part, a culturally distinct approach to designs. Duplication offers a means of reverse engineering, a way of understanding how something works. In fact, a number of designs known as gongban (pg 94) regularly circulate openly across factories as templates. The consequence is not only the means of manufacturing something akin to the original, but a way of producing original designs too via customizations that can freely run wild. Lindtner’s punchline in all of this is that the copy is essentially the prototype.

Of course, bootstrapping manufacturing pipelines for existing products does have the consequence of building a Western perception of Chinese manufacturing as a sort of copycat. Lindtner engages with this idea as well, noting how some Western maker labels devote extra work to qualify their means of production in China as genuine (think Arduino “Genuino”) while others emerging directly from China like Seeed Studio have had to push through this perception to break into Western markets.

With gongban, manufacturing in China has developed under circumstances where unlicensed sharing is the norm. In a way, this culturally distinct approach challenges the Western style of binding designs to terms set by the creator. It’s almost as if the west were to operate with permissive open source licenses being the default, and it begs the question: what kinds of innovation we would see if this kind of relationship to designs existed in the west?

The Politics at Play

None of this manufacturing growth has happened in a vacuum. It turns out that a collection of forces loosely motivate this sort of rapid manufacturing development in China.

First, the Chinese Communist Party (CCP) has somewhat adopted the promise of the maker movement and used it, in part, to spur economic growth by creating a strong connection between making and entrepreneurship. Here, starting off as maker puts you on a path towards happiness by ultimately starting your own business. It’s no coincidence that the west now regularly sees Shenzhen as the “Silicon Valley of Hardware.” Both careful branding and financial investments via recognizing Shenzhen as a “Special Economic Zone” have made this the case.

On the other hand, the capacity to manufacture electronics cheaply has also brought in business from the west. Lindtner notes a number of Western articles comparing manufacturing in China as “going back in time,” and she ties this frontier-like perception to other scholarship that digs into the aftermath of Western colonialism. Overall, the politics between west and east are vastly complicated, and this section of the book makes for an eye-opening read.

And Much More

This article is only teasing you with a few highlights. Fret not, Dear Reader, with just over 220 pages and a thick bibliography to sink your teeth into, there’s plenty left to walk through. If you’ve ever been curious to step into the world of manufacturing in China, this book is a must-read. Give yourself a few afternoons, and let the details of prototyping in China draw you in.

Off-the-shelf stock parts are the blocks from which we build mechanical projects. And while plenty of parts have dedicated uses, I enjoy reusing them in ways that challenge what they were originally meant for while respecting the constraints of their construction. Building off of my piece from last time, I’d like to add to your mechanical hacking palette with four more ways we can re-use some familiar off-the-shelf parts.

O-Rings as Retention Features

Plenty of us are using rubber o-rings as airtight seals between static or moving parts. But their elastic and grippy properties give them a second life in other places involving removable components.

On my tool-changing machine, Jubilee, I quickly ran into the issue of securing idle tools onto their parking posts without the risk of letting them fall out. While one tool is being used, the remaining idle tools need to sit in a fixed location so that the machine’s carriage can pick them up later. To complicate the matter, the motion platform creates an appreciable amount of vibration, and idle tools that aren’t secured down are prone to slip out.

I’ve seen plenty of tool-changer builders opt for magnets in this case. They’re fairly compact, and you simply place one on the tool and another on its corresponding parking post. In my case, though, I opted for o-rings instead. Here, I use them to apply a bit of preload “squish” that secures the tool body to the metal pins of its parking post. The result is that tools slide into place with a small, satisfying amount of force and stay fixed even as the machine vibrates.

O-rings have the slight disadvantage in that their performance can be somewhat dependent on the accuracy of the 3D printer used to print the part that they will be installed into. In my first experiments, the fit was too tight. In others, too lose. If you find yourself in those cases, dear reader, know that two quick fixes include both (a) switching materials from neoprene to silicone, and (b) adding a tiny amount of grease to the parking post pins.

Overall, I’ve found this solution to be a reliable alternative to magnets, not to mention being widely available and still inexpensive.

DIY Thrust Bearing Retainer Rings

Thrust bearings often come in three pieces, that is: a set of steel balls locked inside a retainer ring and two washers to sandwich it. For the majority of my professional and unprofessional affairs, I’ll usually start by look through Torque Transmission’s catalog. But since I occasionally kept wishing I could customize my thrust bearing sizes, and since replacement balls are available on McMaster-Carr, I eventually tried rolling my own–to modest success!

To do so, I started by laser-cutting the center retainer ring out of Acetal (aka: Delrin), on of my favorite materials for prototyping. Both the low friction and clean laser cut edges make it a great choice for this application. After playing around with the hole diameter to seat the balls, I found a size where each ball would barely poke through the bottom of the ring without falling out. This trick is courtesy of the laser beam’s kerf, which puts a slight angle on the cut edge and makes each ball sit in a hole that resembles more of a cone if you zoomed in.

For the washers, I scoured Misumi’s catalog for thick steel shim rings. Combined, this approach gives me much more flexibility in acquiring thrust bearings in nearly arbitrary sizes.

There are a couple drawbacks with this approach. By far, the biggest issue is that a sad, tweezer-equipped human must load a bearing ball into each hole manually–a potentially arduous task for tiny balls that are all-too-eager to escape your fingernails and make a run for the nearest hallway, never to be seen again. The other issue is that the stainless steel shim rings I chose simply aren’t as hard as the Rockwell 60 hardened steel washers that the commercial parts use. The result is that the bearing balls will wear a small, circular channel into the shim ring. That said, that’s not a huge issue for applications that wont experience heavy loads.

Nowadays, I like to think of this entire approach as a bad idea–except when it’s not! Creating your own cages gives you the flexibility to define the inner and outer hole diameter. And for prototyping a one-off system, I may yet again reach for this trick.

COB LED Strips for Microscope Illumination

Taking pictures with the benchtop microscope first poses the challenge of illuminating your tiny subjects with enough light. Sometimes the microscope comes with its own light source. Other times, you can purchase a ring light attachment like this one from Aliexpress. Unfortunately, these light rings don’t always come in the sizes you need. And in cases where you’re working with oddly-sized lens bodies, sometimes you just need something custom.

In those cases, I’ve been tempted to fire up KiCAD and make a custom LED ring PCB. But while that certainly works, the voice in the back of my head keeps asking: isn’t there an easier way to do this? After letting the thought simmer in the back of my head, I found an answer: side-emitting COB LED strips.

For this sort of application, these LED lights are almost perfect. For one, they’re extremely flexible, capable of tucking into very small diameters. They can also be cut-to-length, giving you lots of flexibility on the size you might need. And with their adhesive backing, you can simply peel-and-stick the length to the cylindrical body you’re illuminating.

I ended up using this trick on Jubilee’s “camera inspection tool.” The result works perfectly for this sort of space-constrained setup.

It’s worth mentioning that the adhesive on the back of this LED strip isn’t super thrilled at being rolled into very small diameters. But in those cases, you can always reach for a zip tie for extra security. And, dear reader, if you’re convinced that a solid LED ring will still fit your needs better, I invite you to also consider “Angel Eye” LED headlights on Aliexpress.

Seamless Stainless Steel Tubes as Coarse Linear Guides

On occasion, my after-hours web-browsing habit of sifting through part catalogs uncovers some enlightening results. Recently, I discovered seamless stainless steel tubing. These are hollow stainless tubes available in a wide range in inner/outer diameter combinations. Seeing them instantly had me fantasizing about using them as coarse linear guides. And, combined with the right complimentary part, it turns out that they work surprisingly well for that purpose.

On their own, I discovered that the tolerances of the 8 millimeter tubes just aren’t good enough to simply attach an LM8UU linear bearing. Some tubes worked, but others were simply too large to fit the bearing. However, Drylin LM8UU Bushings offer a nice workaround for rods with a less well-defined outer diameter. These bushings are sold as sliding replacements to roller bearings. They’re made from an especially low-friction plastic and sold with slightly oversize inner diameters. To install them, one must tighten them down with just the right force such that bushing slides along the rod smoothly without binding or wiggling. This installation quirk makes them perfect for pairing with these tubes. You simply adjust the clamping forces until the setup slides smoothly.

In contrast to hardened steel rods, these hollow tubes are extremely light–only 25 grams per 150 millimeters of tube length. These tubes are also easy to cut to length with mere hand tools. Here, a handheld tube cutter easily cuts these stock tubes down to size.

For my test application, I cooked up a syringe head for Jubilee. Here, a sliding piece attaches to the plunger of a typical 10 cc syringe, and a motor-driven leadscrew actuates it. Overall, the setup works really well for this type of low precision application. I will certainly keep this trick in one of my pockets, and I hope you do too.

Stock Part Slant Rhymes

That wraps up this B-Sides showcase for now. I hope this round of stock part “phonics” keeps you looking for new ways we can reuse everyday stock parts. And if you find something clever, do drop us a tip!

Last year, I found myself compelled to make a scaled-down replica of the iconic test chamber signs from the video game Portal. If you’ve played the game, you’ll remember these signs as the illuminated monoliths that postmarked the start of every test chamber. In hyperstylized video game fashion, they were also extremely thin.

True to the original, my replica would need to be both slimmed down and backlit with a uniform, natural white glow. As fate would have it, the crux of this project was finding a way to do just that: to diffuse light coming in from the edges so that it would emit evenly from the front.

What I thought would be quick project ended up being a dive down the rabbit hole that yielded some satisfying results. Today, I’d like to share my findings and introduce you to light guide plates, one of the key building blocks inside of much of today’s backlit screen technology. I’ll dig into the some of the working principles, introduce you to my homebrew approach, and leave you with some inspirational source code to go forth and build your own.

Hobby and Industry Practices

Tackling this project made me wonder: how do manufacturers in the electronics industry illuminate those ultra-flat laptop displays and TV screens to get a perfectly uniform glow? Following a bit of internet research, I discovered a treasure trove of useful insights.

Before we dive too deep into how the consumer electronics industry solves this problem, I want to first walk you through an analogous hacker side-project: the laser-cut acrylic edge-lit display. We’ve featured quite a few projects like these on Hackaday, and they’re just the right level of complexity to get your feet wet at the local Hackerspace.

The core concept is that clear acrylic sheets have the ability to act as fiber optics, piping light from one edge to the other. The journey isn’t perfectly straight though. Much of the light enters at an angle, bouncing back and forth between top-and-bottom surfaces before exiting the other edge. By etching a pattern on one surface of the acrylic, we create a location where the light is absorbed and emitted, rather than mostly reflected. We can take advantage of this quirk to create some pretty swanky looking signage.

Something that careful observers might point out: image features that are further away from the light source are noticeably dimmer. To understand that phenomenon, we need a bit of physics.

Some Background Theory: Snell’s Law

Some fairly simple optics theory behind this hacker project can help us understand what’s going on. Let’s start with a cutaway side view of this project where the left side is illuminated by a bar of LEDs.

In this setup, a light source shines from one edge of the plate, sending light rays into the plate at a range of angles. It turns out that there exists special angle Φ_c called the critical angle. Light rays hitting the surface boundary at less than Φc will exit the plate immediately at a slightly different exit angle according to Snell’s law. Light rays hitting the surface at angles greater than or equal to Φc will be totally internally reflected. In other words, they will continue to bounce around inside the plate at a fixed angle forever, unless they are interrupted. For glass and plastic, Φc ≈ 42°.

By etching the surface of the plate, we create locations where the internally reflected light rays can scatter and exit the plate at a specific location, rather than reflect back internally. This is the phenomenon that causes the signs to glow.

At this point you might be able to guess why etched features of the sign become dimmer as they get further from the light source. It’s because a larger portion of the internally reflected light rays have already exited the plate earlier on.

Industry Practices

It turns out that LCD manufacturers implement a backlighting scheme that uses a similar approach to what we’ve seen so far. Peel back the inside of a liquid crystal display to find that it actually consists of a sandwich of many layers. Separate those layers to find a polarizing layer, a liquid crystal layer, a diffuser layer, clear fiber optic sheet, and finally a thin reflective backing layer. This thin fiber optic sheet, called a light guide plate, is illuminated from the screen edge with a bar of LEDs. The goal of this plate is to take internally reflected light from the edge and release it in a controlled fashion along the surface such that the front of the screen is evenly lit.

Similar to the sign projects from above, manufacturers mark the surface of the sheet with a pattern of dots, creating escape points for the light to exit along the way. The diffuser layer takes the illuminated light from this pattern and diffuses it further into a uniform light source, and the reflective layer prevents the light from escaping prematurely out the wrong side.

Beyond these basics, though, is where manufacturers start to differ in their own tweaks to this recipe. First off, light guide plates can be made from either acrylic or polycarbonate. They can be either flat or slightly “wedge-shaped,” where the angle of the wedge helps distribute the light more evenly. They can be marked by laser (acrylic only) or by injection mold where the mold actually carries small detents to transfer the pattern. Finally, the dot pattern can vary in density according to a polynomial or exponential function.

From my background reading, I was pleasantly surprised that plenty of vendors will also sell you a host of items relevant to making displays. Reach out to 3M, and you’ll likely hear back with a host of polarizers and “brightness-enhancement” sheets all intended for this purpose. Dig through Aliexpress, and  you’ll find vendors offering you a range of “backlight bars” of component LEDs made to replace those found in laptop and tv screens. Dig deeper, and you’ll even find vendors offering made-to-order acrylic panels with a diffuser grid pattern etched onto them, although the pattern options are somewhat limited.

The Homebrew Light Guide Plate Approach

Inspired by my reading, I started with a first-draft making my own sandwich for my Portal sign. While it turns out that you can buy many of the real materials that go into actual LCD panels by 3M, they come at a hefty pricetag in low quantities, so I settled for some cheaper reflective substitutes. My final stack consisted of:

• PET overhead transparency with the Portal sign replica printed on the surface
• 3 mm opaque white cast acrylic, laser-cut to size
• 3 mm clear cast acrylic, laser-cut to size and etched with a diffuser pattern
• Solar Window Tint Film from Tap Plastics

The stars really aligned well for this project to be something anyone with a CO2 laser cutter nearby can tackle. First, most of the raw materials are either readily available, or cheaper substitutes exist. Second, by nature of these panels being laser cut, the panel edge gets a nice flame polish in the process of being made. This is critical to increase the amount of light entering the panel. Overall, I was thrilled to be doing most of the fabrication in the home workshop.

Quick and Dirty First Drafts

To find out how much effort I’d need to put into makinig an even backlight, I started with something simple. I started by making an evenly-spaced grid etched on the surface of the clear acrylic, covered the bottom with the window tint film, and illuminated it from two sides with two LED backlight bars. As a quick test, I covered the panel with the opaque white sheet and observed it from a distance.

Unfortunately, the results weren’t convincing, but I learned plenty from this setup.

It was clear that the stackup was noticeably dimmer in the middle, the furthest point from the light sources, and the effect was even worse on camera. After another trial, I also noticed that there was an upper limit on how far apart I could space the pattern elements before they started appearing through the diffuser as discrete light sources. I was hoping to avoid writing some custom software to generate the panel pattern, but here we go.

Diffusing Light–Now with BSplines

At this point, I realized that I needed some finer control on these laser parameters, so I cooked up a Python notebook to generate a panel of specified XY dimensions with a custom dot pattern and write the result to an SVG file. For tuning knobs, I wanted to be able to manipulate dot density as a function of distance from the light source. To do so, I created an interactive 2D graph where I could drag around 5 points, and fit them to a second order B-Spline. The result looked like so:

This script I wrote had some nice constraints on it. First, I could enforce a maximum dot spacing so that the script would never generate a pattern that was so sparse that it would appear as discrete light sources. Next, I could mirror the results to apply the pattern to a panel illuminated from two sides. Finally, I could actually record the parameters of my test pieces.

Armed with some new software tooling, I started generating squatty light guide plate samples, illuminating them from both sides under the diffuser, and checking the results. After about 6 tries, I had something good enough to fool me–and my camera!

Feeling comfortable with my settings, I cut a full size piece and assembled my final light plate sandwich.

And, without further ado: the final results after assembly.

It’s not 100% perfect, but it’s more-than-convincing for both my eyes and for smartphone cameras. It’s also light years ahead of my original naive approach.

As far as software goes, there are plenty of usability improvements worth adding. It would also be a worthy exercise to try to derive the density curve from a calibration image, a flat field correction of sorts. But I’ll leave those items as an exercise for the reader.

We do what we must. because. we can.

This is one of those projects that I was hoping someone had already written up so that I could adopt their results (and credit them, of course!) and use them in my project. In this case, I had to roll up my sleeves and be that someone. But I’m happy to report back with the fruits of my labor. If you’re curious enough to follow this rabbit hole, you are most welcome to have a go at my crude light guide plate generator notebook. Who knows? Maybe in the future, this sort of feature will get integrated into other laser software packages if we ask nicely.

References

• Light Guide Techniques Using LED Lamps. Agilent’s Application Brief I-003.
• optimal dimension of edge-lit light guide plate based on light conduction analysis (Optics Express, Vol 29, Issue 12. 2021)
• Liquid crystal display and organic light-emitting diode display: present status and future perspectives. Light Sci Appl 7, 17168 (2018)
• DF2000MA 8in. x 10in. Reflective Backing layer by 3M, available on Digikey

Those who hibernate in their workshops have a habit of re-imagining their relationship to tools. And [Marius Hornberger] is no exception, but the nine upgrades he’s added to his grandfather’s old drill press puts this machine on a whole other level.

In proper storytime fashion, [Marius] steps us through each upgrade, the rationale, and the time and effort that went into crafting the solution. Some of these upgrades, like a digital readout (DRO), add modern features to an old-school device. Others, like an oil mist cooling system and a compressed air chip blower, borrow from other machines with similar setups. Some, like the chip guard, are nice personal touches. And a few, like the motorized table with automatic clamp, transform the entire operator experience. On the whole, these upgrades follow a gentle theme of personalizing the machine to [Marius’] tastes, giving him a delightful, more personal operator experience that’s tuned through his everyday use. Amid the sheer volume of tweaks though, we’re convinced that you’ll find something that tickles your tinkering fancy.

It’s worth mentioning that the pneumatic table clamp alone (at 4:28) makes the entire video worth the watch. If you’ve ever had the mishap of pinching your finger or struggling to hold the table steady while clamping it in place, this little upgrade takes all of that away, replacing the swivel handle with a homebrew pneumatic cylinder made in the shop. With a single button press, a swoosh of compressed air either clamps or releases the table. Best of all, the setup still sports a hand clamp if [Marius] is operating without a compressed air source.

It’s also worth mentioning that a couple of [Marius’] upgrades completely skip the CAD step altogether. Instead, [Marius] creates templates directly off the drill press with tracing paper and then immediately transfers them onto stock materials. It’s a nice reminder that not every small project needs to start with a 3D model.

If all these upgrades are getting you ready to modify your machine, look no further than the video description where he’s courteously posted inks to key components behind these upgrades.

The story of many-a-workshop often involves reinventing your machine tools. If you’re looking for more tales of tool upgrades, have a look at resurrecting a machine from literal ashes or a machine that improves itself.

[Steven Bennett] is so fond of Dyson’s new Lightcycle lamp that he’s decided to clone his own version in the spirit of the original. Dyson, however, knows what makes their lamp so special — so much that they patented their technique for tucking away the power wiring. Undaunted, [Steven]’s latest challenge has been to create a cable management solution that captures the elegance of the original without making a flat-out duplicate.

[Steven]’s latest update starts with the details of the original model’s patent. In a nutshell, Dyson’s elegance comes from both a flat cable (a flex PCB, perhaps?) and a magnetic interface that transfers power between the two primary structural beams. The latter half discusses [Steven]’s alternate solution: a miniature drag chain that can be 3D printed to arbitrary lengths. Like the flat flexible cable, this cable rides in the groove of the lamp’s two structural beams; but unlike the original, it spools outwards into a hoop on one end of its travel length. Overall [Steven] is quite happy with this result, and we think this solution gives the lamp a charm that’s distinctly original.

Capturing the design essence doesn’t just stop at wire management though. Have a look at some previous video logs in the series to get a sense of some of the other challenges faced in both heat dissipation and mechanical feel.

Wire management, when done well, scratches a design itch somewhere in the back of our heads. If you’re curious for more cable management solutions, have a look at some of these other tricks that use tape measure or involve a DIY coiling method.

Board space is a premium on small circuit board designs, and [Alvaro] knows it. So instead of adding a separate programming port, he’s found a niche USB-C feature that lets him use the port that he’s already added both for its primary application and for programming the target microcontroller over JTAG. The result is that he no longer needs to worry about spending precious board space for a tiny programming port; the USB-C port timeshares for both!

In a Twitter thread (Unrolled Link), [Alvaro] walks us through his discovery and progress towards an encapsulated solution. It turns out that the USB-C spec supports a “Debug-Accessory Mode” specification, where some pins are allowed to be repurposed if pins CC1 and CC2 are pulled up to Logic-1. Under these circumstances, the pin functions are released, and a JTAG programmer can step in to borrow them. To expose the port to a programmer, [Alvaro] cooked up a small breakout board with a USB-C plug and separate microcontroller populated on it.

This board also handles a small quirk. Since [Alvaro’s] choice of programming pins aren’t reversible, the USB-C plug will only work one of the two ways it can be plugged in. To keep the user informed, this breakout board sports a red LED for incorrect orientation and a green LED for correct orientation–nifty. While this design quirk sacrifices reversibility, it preserves the USB 2.0 D+ and D- pins while also handling some edge cases with regard to the negotiating for access to the port.

Stick through [Alvaro]’s Twitter thread for progress pics and more details on his rationale behind his pin choices. Who knows? With more eyes on the USB-C feature, maybe we’ll see this sort of programming interface become the norm?

[Alvaro] is no stranger to Hackaday. In fact, take a tour back to our very first Supercon to see him chat about shooting lasers at moving targets to score points on a DEFCON challenge in the past