Expanding The K40 Laser Cutter With Aluminum Extrusion

July 19, 2018 by Brian Benchoff 34 Comments

The K40 laser cutter is an excellent option if you need to laze some plywood or acrylic. It’s ubiquitous, it’s cheap, and there’s a vast community out there that will help you support any issue you could have. Unfortunately, the K40 laser cutter is lacking. It has a small bed, and it doesn’t have the latest technology like ‘switches’ that turn off the laser when you open the door.

[frederik] recently upgraded his K40 to something great. He’s calling it the Layzor, and it has a huge 600×400 mm bed area, a feed-through slot for even wider workpieces, and fancy technology [frederik] is calling an ‘E-stop’. Sounds expensive, doesn’t it?

The build began by scavenging the K40 laser cutter for the electronics and laser tube, then building a new frame out of aluminum extrusion. A few parts had to be custom made, including a few stepper motor mounts and something to hold the laser tube. All of this was tied up in a box with acrylic panels, and went together as easily as any other CNC machine.

The finished project is great. It’s a relatively powerful laser cutter capable of most hobby work, and it was cheap. The total cost for this build was under €500. That’s not including the scavenged K40, but that’s still an amazing price for a very capable laser cutter.

Dual Source Laser Cutter Built Like A Tank, Cuts Most Anything

July 15, 2018 by Richard Baguley 15 Comments

Laser cutters aren’t the sort of thing that you might think about making at home, but there’s no reason not to if you are careful and do your research. That’s what [Daniele Ingrassia] did with the Laser Duo, an open source laser cutter that has two light sources for cutting various materials. His final product is not a small device: it has a press-formed aluminum case that looks more like a World War I tank than a piece of precision machinery. But that’s for a good reason: you don’t mess about with lasers, especially the 130 Watt CO2 and 75 Watt Yag lasers that the Laser Duo uses. Continue reading “Dual Source Laser Cutter Built Like A Tank, Cuts Most Anything” →

Chinese Laser AK-47: Myth Or Reality?

July 9, 2018 by Steven Dufresne 164 Comments

Chinese company ZKZM Laser has produced the ZKZM-500 laser assault rifle which people are calling the Chinese AK-47 because of its similar size, weighing in at three kilos (6.6 lbs). Claims of its capabilities, however, are being disputed.

The South China Morning Post writes that the company claims the laser to:

be powered by a rechargeable lithium battery back,
have a range of 800 meters (0.5 miles),
have a beam that is invisible to the eye,
be able to fire 1000 “shots”, each no longer than two seconds,
be able to burn human flesh if held in place long enough,
be able to set fire to clothes and hair, and
be able to set fire to banners from a distance.

Burning things with lasers is nothing new but the disputes are mostly based around such a small laser being effective at an 800 meter range. To be fair, while the 800 meter range claim is everywhere, the Post writes that the company brochure says the range is 500 meters (0.3 miles), still quite a long distance.

[styropyro], a YouTuber with a lot of experience with lasers has done an analysis, starting by deducing a wavelength of around 2000 nanometers. He finds that at 800 meters the beam would have dispersed to a diameter of 26 cm (10 inches) and produce 53 W over that area. (EDIT: The 53 W is how much sunlight would produce for that area. In the video he carries the calculations further to work out the minimum power needed, ignoring losses, to light the cotton on fire, 645 W.) For 500 meters, using the same formula we calculate that the dispersion would be a diameter of 16 cm (6 inches) with 500 W spread over that area, which would get uncomfortable very fast, think of half a square meter of sunlight focused down to a circle of that diameter. (EDIT: Again, this it 500 W for sunlight, the laser produces more.) His video doesn’t include enough detail for us to replicate the remainder of the calculations so we’ll just have to go with the 800 meter claim. See the video below for his full analysis. If anyone else has any experience that’ll either support or dispute the claims then please share it with us in the comments.

After all the disputes against their claim, the Chinese company did produce a video firing the laser from a shorter distance. Check it out on this page by the post.

While waiting to see how much truth there is to the Chinese company’s claims we can sit back and enjoy [styropyro’s] home-brew high power ruby laser, both his build and him doing some serious damage with it.

Oh, and don’t try this at home. It’s probably in violation of the Geneva Convention on Certain Conventional Weapons in addition to common sense.

Continue reading “Chinese Laser AK-47: Myth Or Reality?” →

Worn Train Rails Get Judged By Laser

July 8, 2018 by Donald Papp 32 Comments

[Calango] is a railway technician, and for a school final project created the Rail Wear Surveillance Trolley (RWST) which is a delightfully designed device made mainly from PVC conduit with one job: travel down a segment of train track while shining a green laser onto the rail, and capture camera images. The trolley holds both the laser and the camera at just the right angles for the camera to capture a profile of the rail’s curved surface. The images are sent via Bluetooth to a smartphone for later analysis. Rail wear can be judged by checking how well the profile of the rail conforms to the ideal profile of an unworn segment. The trolley is manually pushed by an operator, but [Calango] says that ideally, it would be self-propelled and able to inspect a length of the track then return on its own.

The project was made on a tight budget, which led to some clever solutions like using a rotary encoder attached to a wheel as a makeshift distance sensor. If things get desperate enough, it’s even possible to roll your own rotary encoder with a 3D printer and two microswitches.

Laser Draws Weather Report

June 23, 2018 by Rich Hawkes 13 Comments

Have you ever wished that a laser could tell you the weather? If you have, then [tuckershannon] has you covered. He’s created a machine that uses a laser and some UV sensitive paper to draw the temperature and a weather icon! And that’s not all! It’s connected to the internet, so it can also show the time and print out messages.

Building on [tuckershannon]’s previous work with glow-in-the-dark drawing, the brains inside this machine is a Raspberry Pi Zero. The laser itself is a 5mw, 405nm laser pointer with the button zip-tied down. Two 28BYJ-48 stepper motors are used to orient the laser, one for the rotation and another for the height angle. Each stepper motor is connected to a motor driver board and then wired directly to the Pi.

The base and arm that holds the laser were designed in SolidWorks and then 3d printed. The stepper motors are mounted perpendicular to one another and then the laser pointer mounted at the end. The batteries have been removed from the laser and the terminals are also wired directly to the raspberry pi. The Pi is then connected to Alexa via IFTTT so that it can be controlled by voice from anywhere.

The real beauty of [tucker]’s laser drawing machine is that is will draw out the temperature and weather icon, as well as drawing the time in either digital or analog forms! We’ve seen [tuckershannon]’s work before. The precursors to this project were his clock which uses a robotic arm with a UV LED on it to draw the time and another clock which uses similar robotic arm only with a laser attached. Let’s hope we get to see the rest of [tucker]’s progress!

Continue reading “Laser Draws Weather Report” →

Laser Cutter Turns Scrapped To Shipped

June 19, 2018 by Tom Nardi 25 Comments

We’ll go way out on a limb here and say you’ve probably got a ridiculous amount of flattened cardboard boxes. We’re buying more stuff online than ever before, and all those boxes really start to add up. At the least we hope they’re making it to the recycling bin, but what about reusing them? Surely there’s something you could do with all those empty shipping boxes…

Here’s a wild idea…why not use them to ship things? But not exactly as they are, unless you’re in the business of shipping big stuff, the probably won’t do you much good as-is. Instead, why not turn those big flattened cardboard boxes into smaller, more convenient, shippers? That’s exactly what [Felix Rusu] has done, and we’ve got to say, it’s a brilliant idea.

[Felix] started by tracing the outline of the USPS Priority Small Flat Rate Box, which was the perfect template as it comes to you flat packed and gets folded into its final shape. He fiddled with the design a bit, and in the end had a DXF file he could feed into his 60W CO2 laser cutter. By lowering the power to 15% on the fold lines, the cutter is even able to score the cardboard where it needs to fold.

Assuming you’ve got a powerful enough laser, you can now turn all those Amazon Prime boxes into the perfect shippers to use when your mom finally makes you sell your collection of Yu-Gi-Oh! cards on eBay. Otherwise, you can just use them to build a wall so she’ll finally stay out of your side of the basement.

[Thanks to Adrian for the tip.]

Continue reading “Laser Cutter Turns Scrapped To Shipped” →

Joe Grand Is Hiding Data In Plain Sight: LEDs That Look Solid But Send A Message

June 10, 2018 by Mike Szczys 19 Comments

Thursday night was a real treat. I got to see both Joe Grand and Kitty Yeung at the HDDG meetup, each speaking about their recent work.

Joe walked us through the OpticSpy, his newest hardware product that had its genesis in some of the earliest days of data leakage. Remember those lights on old modems that would blink when data is being transmitted or received? The easiest way to design this circuit is to tie the status LEDs directly to the RX and TX lines of a serial port, but it turns out that’s broadcasting your data out to anyone with a camera. You can’t see the light blinking so fast with your eyes of course, but with the right gear you most certainly could read out the ones and zeros. Joe built an homage to that time using a BPW21R photodiode.

Transmitting data over light is something that television manufacturers have been doing for decades, too. How do they work in a room full of light sources? They filter for the carrier signal (usually 38 kHz). But what if you’re interested in finding an arbitrary signal? Joe’s bag of tricks does it without the carrier and across a large spectrum. It feels a bit like magic, but even if you know how it works, his explanation of the hardware is worth a watch!

Continue reading “Joe Grand Is Hiding Data In Plain Sight: LEDs That Look Solid But Send A Message” →