Laser Hacks

634 Articles

Laser Focus Made Easier With IR Filter

March 9, 2021 by 13 Comments

If you’ve used a diode laser engraver or cutter, you know that focus is critical. You’d think it would be relatively simple to get a sharp focus, but it isn’t that simple. [Makers Mashup] shows in a video how to use an adjustable IR filter to cut out all the light bleed to get a sharp image to make focusing simpler.

The filter he shows adjusts from 530nm to 750nm and is made to screw into a 72mm lens, but it works fine with your eyeballs, too. [Makers Mashup] says he’ll eventually make a stand for it so he can look through it with both hands free.

Continue reading “Laser Focus Made Easier With IR Filter” →

Laser Zap That Mosquito

March 8, 2021 by 98 Comments

When we first heard of [Ildar Rakhmatulin’s] plan to use OpenCV on a Raspberry Pi to detect mosquitos and then zap them with a 1 watt laser, we thought it was sort of humorous. However, the paper points out that 700,000 people die each year from mosquito bites — we didn’t verify that, but according to the article that’s twice the number of people murdered each year. So the little pests are pretty effective assassins.

It looks as though the machine has been built, at least in a test configuration. A galvanometer aims the death ray using mirrors, and with the low power and lossy mirrors the mosquitos can only be a small distance from the machine — about a foot.

Continue reading “Laser Zap That Mosquito” →

Hands On With The Ortur Laser Cutter

February 23, 2021 by 63 Comments

I couldn’t write very much without a computer. Early in my career, I wrote with a typewriter. Unless you are pretty close to perfect — I’m not — it is very frustrating to make edits on typewritten stuff. The equivalent in the real world, for me, has been 3D printers and CNC machines. I can visualize a lot of things that I’m not careful enough to build with normal tools. Despite my 7th-grade shop teacher’s best efforts, everything I did turned out to be a toothpick or a number 7. But I can get my ideas into CAD and from there the machines do the rest. That’s why I was excited to get a laser cutter this past Christmas. You might wonder why I’d need a laser cutter if I have the other tools. Then again, if you read Hackaday, you probably don’t need me to explain why you need a new gadget. I’ve had my eye on a laser for a good long time, but recent developments made it more attractive. I thought I’d share with you some of what I’ve found getting started with the Ortur laser cutter. The cutter is easy to put together and costs somewhere in the $200-$400 range depending on what you get with it. I thought I’d take some time to share what I’ve learned about it.

Why a Laser?

If you haven’t had experience with a laser cutter or engraver before, you might think it is a very specific instrument. Sure, the Ortur is good at engraving some things (but not all things). It can cut some things, too, but not as many things as a big serious laser cutter. However, creative people find lots of ways to use cutting and engraving to produce things you might not expect.

Continue reading “Hands On With The Ortur Laser Cutter” →

Homebrew Doorknob Caps For High-Voltage Fun

February 19, 2021 by 15 Comments

Mouser and Digi-Key are great for servicing most needs, and the range of parts they offer is frankly bewildering. But given the breadth of the hardware hacking community’s interests, few companies could afford to be the answer to everyone’s needs.

That’s especially true for the esoteric parts needed when one’s hobby involves high voltages and homemade lasers, like [Les Wright]. He recently came up with a DIY doorknob capacitor design that makes the hard-to-source high-voltage caps much easier to obtain. We’ve seen [Les] use these caps in his transversely excited atmospheric (TEA) lasers, a simple design that uses high-voltage discharge across a long, narrow channel filled with either room air or nitrogen. The big ceramic caps are needed for the HV supply, and while [Les] has a bunch, they’re hard to come by online. He tried a follow-up using plain radial-lead ceramic capacitors, and while the laser worked, he did get some flashover between the capacitor leads.

[Les]’s solution was to dunk the chunky caps in acetone for a week or so to remove their epoxy covering. Once denuded, the leads were bent into a more axial configuration and soldered to brass machine screws. The dielectric slug is then put in a small section of plastic tubing and potted in epoxy resin with the bolts protruding from each end. The result is hard to distinguish from a genuine doorknob cap; the video below shows the build process as well as some testing.

Hats off to [Les] for taking pity on those of us who want to replicate his work but find ourselves without these essentials. It’s nice to know there’s a way to make unobtanium parts when you need them.

Continue reading “Homebrew Doorknob Caps For High-Voltage Fun” →

MIT Prints Robots With Lasers

February 12, 2021 by 9 Comments

MIT’s Computer Science and Artificial Intelligence Lab (CSAIL) wants to convert laser cutters into something more. By attaching a head to a commercial laser cutter and adding software, they combine the functions of a cutter, a conductive printer, and a pick and place system. The idea is to enable construction of entire devices such as robots and drones.

The concept, called LaserFactory, sounds like a Star Trek-style replicator, but it doesn’t create things like circuit elements and motors. It simply picks them up, places them, and connects them using silver conductive ink. You can get a good idea of how it works by watching the video below.

Continue reading “MIT Prints Robots With Lasers” →

3D Printer? Laser Cutter? CNC? Yes, Please

February 10, 2021 by 60 Comments

Most of us have, or, would like to have a 3D printer, a laser engraver, and a CNC machine. However, if you think about it naively, these machines are not too different. You need some way to move in the XY plane and, usually, on the Z axis, as well.

Sure, people mount extruders on CNCs, or even lasers or Dremel tools on 3D printers. However, each machine has its own peculiarities. CNCs need rigidity. 3D printers should be fast. Laser engravers and CNCs don’t typically need much Z motion. So common sense would tell you that it would be tough to make a machine to do all three functions work well in each use case. [Stefan] thought that, too, until he got his hands on a Snapmaker 2.0.

As you can see in the video below, the machine uses different tool heads for each function. The motion system stays the same and, curiously, there are three identical linear motion modules, one for each axis.

Continue reading “3D Printer? Laser Cutter? CNC? Yes, Please” →

DVD Optics Power This Scanning Laser Microscope

February 2, 2021 by 35 Comments

We’ve all likely seen the amazing images possible with a scanning electron microscope. An SEM can yield remarkably detailed 3D images of the tiniest structures, and they can be invaluable tools for research. But blasting high-energy cathode rays onto metal-coated samples in the vacuum chamber of a bulky and expensive instrument isn’t the only way to make useful images, as this home-brew laser scanning microscope demonstrates.

This one comes to us by way of [GaudiLabs], a Swiss outfit devoted to open-source lab equipment that enables citizen science; we saw their pocket-sized thermal cycler for PCR a while back. The basic scheme here is known as confocal laser scanning fluorescence microscopy, where a laser at one wavelength excites fluorescent tags bound to structures in a sample. Light emitted by the tags is collected, and a 3D image is built up from multiple scans of the sample at different focal planes.

Like many DIY projects, this microscope is built from old DVD parts, specifically the pickup heads. The precision optics in these commonly available assemblies, which are good enough to read pits as small as 150 nm on a Blu-Ray DVD, are well-suited for resolving similarly sized microstructures. One DVD pickup is used to scan the laser in the X-axis, while the other head is modified to carry the sample and move it in the Y-axis. The pickup head coils and laser are driven by an Arduino carried on a custom PCB along with the DVD heads. Complete build files are posted on GitHub for anyone interested in recreating this work.

We love tips like this that dig back a bit and find things we missed the first go-around. And the equipment [GaudiLabs] lists really has potential for the budding biohacker, which we also like.

Thanks for the tip on this one, [Bill].