co2

47 Articles

Collaborative Effort Gets Laser Galvos Talking G-Code

July 15, 2022 by 9 Comments

Everyone should know by now that we love to follow up on projects when they make progress. It’s great to be able to celebrate accomplishments and see how a project has changed over time. But it’s especially great to highlight a project that not only progresses, but also gives back a little to the community.

That’s what we’re seeing with [Les Wright]’s continuing work with a second-hand laser engraver. It was only a few weeks ago that we featured his initial experiments with the eBay find, a powerful CO2 laser originally used for industrial marking applications. It originally looked like [Les] was going to have to settle for a nice teardown and harvesting a few parts, but the eleven-year-old tube and the marking head’s galvanometers actually turned out to be working just fine.

The current work, which is also featured in the video below, mainly concerns those galvos, specifically getting them working with G-code to turn the unit into a bit of an ad hoc laser engraver. Luckily, he stumbled upon the OPAL Open Galvo project on GitHub, which can turn G-code into the XY2-100 protocol used by his laser. While [Les] has nothing but praise for the software side of OPAL, he saw a hardware hole he could fill, and contributed his design for a PCB that hosts the Teensy the code runs on as well as the buffer and line driver needed to run the galvos and laser. The video shows the whole thing in use with simple designs on wood and acrylic, as well as interesting results on glass.

Of course, these were only tests — we’re sure [Les] would address the obvious safety concerns in a more complete engraver. But for now, we’ll just applaud the collaboration shown here and wait for more updates.

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Inside An EBay Marking Laser

June 11, 2022 by 13 Comments

When it comes to trolling eBay for cool stuff, some people have all the luck. Whereas all we ever seem to come across is counterfeit chips and obviously broken gear listed as, “good condition, powers on”, [Les Wright] actually managed to get more than he bargained for with one of his recent eBay purchases.

In his video teardown and tour of an industrial marking laser, [Les] suggests that he was really just in it for the optics — which is not a surprise, given his interest in optics in general and lasers in particular. The 20-W CO2 laser once etched barcodes and the like into products on assembly lines, but with a 2009 date code of its own, it was a safe bet that it was pitched due to a burned-out laser tube. But there were still high-quality IR optics and a precision X-Y galvanometer assembly to be harvested, so [Les] pressed on.

The laser itself ended up being built around a Synrad RF-stimulated CO2 tube. By a happy accident, [Les] found that the laser actually still works, at least most of the time. There appears to be an intermittent problem with the RF driver, but the laser works long enough to release the magic smoke from anything combustible that gets in its way. The galvos work too — [Les] was able to drive them with a Teensy and a couple of open-source libraries.

Galvos, lenses worth more than $800, and a working laser tube — not a bad haul. We’ll be following along to see what [Les] makes of this booty. Continue reading “Inside An EBay Marking Laser” →

Large Scale Carbon Capture Without The Technology

May 10, 2022 by 213 Comments

We humans are in something of a pickle, as we’ve put too much carbon dioxide in the atmosphere and caused climate change that might even wipe us out. There may still be people to whom that’s a controversial statement, but knowing something needs to be done about it should be a position for which you don’t necessarily have to be a climate change activist glueing yourself to the gates of a refinery.

It’s obvious that we can reduce our CO2 emissions to tackle the problem, but that’s not the only way that atmospheric CO2 can be reduced. How about removing it from the air? It’s an approach that’s being taken seriously enough for a number of industrial carbon capture solutions to be proposed, and even for a pilot plant to be constructed in Iceland. The most promising idea is that CO2 from power stations can be injected into porous basalt rock where it can react to form calcium carbonate. All of which is very impressive, but is there not a way that this can be achieved without resorting to too much technology? Time for Hackaday to pull out the back-of-envelope calculator, and take a look. Continue reading “Large Scale Carbon Capture Without The Technology” →

This Smart Watch Keeps An Eye On Ambient CO2 Levels

October 30, 2021 by 20 Comments

Human respiration takes in oxygen and in turn, we exhale carbon dioxide. Thus, an uptick of carbon dioxide levels around us can indicate we’re in the presence of other humans, and also, perhaps, the pathogens they carry. To explore this phenomenon, [C Scott Ananian] developed a mod for the Watchy open-source smartwatch, which lets it detect carbon dioxide.

The idea behind the build is simple. If you’re around increased CO2 levels, it may be because you’re surrounded by people, and thus more likely to be exposed to COVID-19. To detect CO2, the watch relies on a Sensiron SCD40 or SCD41 sensor. This is read by the Watchy’s ESP32 microcontroller, and results are graphed on the watch’s e-Paper display. The Watchy is also given a nice new aluminum case to fit the additional hardware.

It’s cool having a graph on your wrist of the ambient concentration of CO2, and at the very least, it could make a good talking point next time you’re at a particularly boring party. You’ll also be more than ready to advise other partygoers if the carbon dioxide level is reaching dangerous levels.

We’ve seen similar builds before, which are useful not only for pandemic safety but also for monitoring if you have any leaks from CO2 storage in the house. If you’ve been working on your own ways to track dangerous gases, be sure to drop us a line!

Hack Your Sodastream With A Giant CO2 Canister

October 14, 2021 by 110 Comments

Sodastream machines are popular amongst people who like to make their own seltzer water at home. However, replenishing the tiny gas canisters is expensive and wasteful. [Becky] decided to upgrade her machine to avoid this problem, and added some smarts while she was at it. 

The simple part of the hack is using an adapter to connect the Sodastream apparatus to a 50 lb CO2 tank from the welding store. This is easy enough, and just uses a off the shelf adapter. Using welding-grade gas in your drinking water is probably a really bad idea, but [Becky] was willing to take the nisk.

However, safety was given due attention in that a CO2 monitor was installed to make [Becky] aware of any dangerous leaks. The tank is also placed on a custom scale built with load cells and an ESP8266, which allows monitoring of how much gas is left. [Becky] notes that at her rate of drinking one bottle a day, the tank should last her a full 7 years or so.

The project brings costs down to 18 cents per liter of seltzer, versus 38 cents for the Sodastream gas supply. It’s likely that the Sodastream prices could still be beat even if a food-safe CO2 source was used. Plus, there’s no need to regularly buy new bottles!

Overall, it’s a great project and one that recalls us of continuous-ink printer hacks. Video after the break.

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A weld bead laid down with homemade CO2

Cooking Up A Batch Of Homebrew Welding Gas

September 21, 2021 by 31 Comments

You know the feeling — you’re making good progress on a weekend project, you’re really in the groove, things are going right. Right up until you run out of That One Thing™ that you can’t do without, the only store that sells it is closed, and you get a sudden case of whiplash as your progress hits a virtual brick wall.

Of course, every challenge holds the opportunity to hack your way around it, which is how [Lucas] ended up building this carbon dioxide generator. The “IG” in MIG welding stands for the “inert gas” that floods the weld pool and keeps the melted metal — the “M” in MIG — from rapidly oxidizing and ruining the weld. Welders often use either straight CO2 or a mix of CO2 and argon as a MIG shielding gas, which they normally get from a commercial gas supplier, generally on non-weekend days.

[Lucas] turned to grade-school chemistry for his CO2 generator, using the vigorous reaction of baking soda and vinegar to produce the gas. Version one was sketchy as all get-out; the second iteration still had some sketch factor thanks to the use of ABS pipe, but the inclusion of a relief valve should prevent the worst from happening. After some fiddling with how to get the reagents together in a controlled fashion, [Lucas] was able to generate enough CO2 to put down a decent bead — a short one, to be sure, but the video below shows that it worked.

Could this be scaled up to something for practical use? Probably not. But it’s cool to see what’s possible, and something to file away for a rainy day. And maybe [Lucas] can use this method to produce CO2 for his homemade laser tube. But again, probably not.

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SYPHCOM, the compact CO2 sensor

Compact Sensor Keeps You Safe By Watching CO2 Levels

August 24, 2021 by 21 Comments

Remember when work meetings were just a bunch of people filling up a small, poorly ventilated room with their exhaled breath? Back in the good old days, all you had to worry about was being lulled to sleep by a combination of the endless slide deck and the accumulation of carbon dioxide. Now? Well, the stakes may just be a little bit higher.

In either situation, knowing the CO2 level in a room could be a handy data point, which is where a portable CO2 sensor like this one could be useful. Or at least that’s [KaRMaN]’s justification for SYPHCOM, the “simple yet powerful handheld carbon dioxide meter.” The guts of the sensor are pretty much what you’d expect — an Arduino Pro Micro, a SenseAir S8 CO2 sensor board, and the necessary battery and charging circuits. But the build does break the mold in a couple of interesting places. One is in the choice of display — a 1980s-era LED matrix display. The HDSP2000 looks like it belongs in a nice bench meter, and is surprisingly legible without a filter. It looks like it flickers a bit in the video below, but chances are that’s just a camera artifact.

The other nice part of this build is the obvious care [KaRMaN] put into making it as small as possible. The layout of boards and components is very clever, making this a solid, compact package, even without an enclosure. We’ve seen CO2 sensors with more features, but for a quick check on air quality, SYPHCOM looks like a great tool.

Continue reading “Compact Sensor Keeps You Safe By Watching CO2 Levels” →