Hackaday Podcast 228: Bats, Eggs, Lasers, Duck Tape, And Assembly Language

July 21, 2023 by 1 Comment

Summer’s in full swing, and this week both Elliot and Dan had to sweat things out to get the podcast recorded. But the hacks were cool — see what I did there? — and provided much-needed relief. Join us as we listen in on the world of bats, look at a laser fit for a hackerspace, and learn how to make an array of magnets greater than — or less than — the sum of its parts. There’ll be flying eggs, keyboards connected to cell phones, and everything good about 80s and 90s cable TV, as well as some of the bad stuff. And you won’t want to miss Elliot putting Dan to shame with the super-size Quick Hacks, either, nor should you skip the Can’t Miss sweep with a pair of great articles by Al Williams.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download a long series of ones and zeroes that, when appropriately interpreted, sound like two people talking about nerdy stuff!

Where to Follow Hackaday Podcast

Places to follow Hackaday podcasts:

Continue reading “Hackaday Podcast 228: Bats, Eggs, Lasers, Duck Tape, And Assembly Language” →

A Shutter Speed Tester With Frickin’ Lasers!

July 7, 2023 by 12 Comments

Buying old cameras is one of the best ways yet found to part a geek from their money, but if you don’t mind finding a few duds along the way it’s still possible to pick up something nice without paying the excessive scene tax of an Etsy seller or an online store. The trouble is, in the many decades during which your purchase went from being pride and joy to forgotten in a drawer to lying on the shelf of a thrift store, its performance may have degraded a little. Does the shutter still operate as it should? How long is a split second anyway? You need a shutter speed tester, and luckily for us, [Stuart Brown] has one.

There are no sharks involved in this build, but it does rely on laser diodes as a light source. There are three of them as well as three sensors, packaged photodiodes with a Schmidt trigger. These feed an Arduino which is hooked up to a TFT display, and the software measures how long each diode receives the light. We’re told it can also measure the raise time on curtain shutters, another important metric.

There’s little in the way of usage examples, but we’re guessing it requires positioning the camera between lasers and photodiodes. We’re curious as to how such an instrument would perform on a camera with a fixed lens, or whether it’s only suitable for those with access to the shutter itself. If this subject interests you, it’s not the first shutter speed tester we’ve shown you.

Header image: Runner1616, CC BY-SA 4.0.

Getting A Rise With Laser Cutting

July 7, 2023 by 6 Comments

Your first 3D print probably seemed pretty amazing. But if you revisit it after a few years, you’ll likely notice it wasn’t nearly as good as you thought. We improve our printers and our processes and the new better results become normal. If you have a laser cutter, you may go through the same iteration. At first, you are happy just to get scorch marks on the workpiece. But when you move to cutting, you want cleaner cuts. You put tape over the work, add air assist, and invest in a honeycomb bed. Each step gets you better results, but you can always improve.

[The Louisiana Hobby Guy] (also known as [Rich]) knows a lot about the practical side of lasers. He suggests using standoff pins to not just secure the part to the honeycomb bed but lift it up a little, allowing air to flow under the part and lets the laser easily cut all the way through. You can see them in action in the video below.

This is a cheap upgrade to prevent flashback when cutting. [Rich] explains how to size them properly and even how to make your own if you don’t want to buy them off the shelf. You can laser cut hold-down pins from plans [Rich] provides, although he prefers to 3D print them, and you can do that, too. Most beds look similar, but if yours is an oddball, you might have to modify them slightly. He has regular dog clamps and the antiflashback standoffs, so you can make some of each. You can also buy them online. Most do not have the antiflashback feature, but at least one vendor that [Rich] points out does have them

If you don’t like the ones [Rich] shows, you can find 3D models for similar pins in the usual places. You can also design them yourself if you want them exactly how you want.

A good thing to add to your laser cutting workflow. [Rich’s] channel is full of great stuff. If you want to know more about air assist, we’ve added it to our cutters. If you are serious about precision cuts, know your kerf, too.

Continue reading “Getting A Rise With Laser Cutting” →

3D Printed Machine Shows How Braiding Is Done

June 21, 2023 by 8 Comments

If there’s something more fascinating than watching cleverly engineered industrial machines do their work, we don’t know what it could be. And at the top of that list has to be the machines that do braiding. You’ve probably seen them, with spools of thread or wire dancing under and around each other in an endless ballet that somehow manages to weave a perfect braid. It’s kind of magical.

For those who haven’t seen such a thing, now’s your chance, with this twelve-spool braiding machine. The building methods that [Fraens] used — mainly 3D printing and laser-cut acrylic — make the workings on this machine plain, even to those of us who never learned to manually braid even three strands. It’s far easier to understand by watching the video below than by trying to describe it, but basically, each vertical supply spool runs along a continuous track around a central point by a series of six meshed gears, passing under each other as they progress around the carousel and forming the braid.

There are a ton of details that go into making this work. Chief among them is the thread tensioning mechanism, which is a lever arm and spring-loaded axle that lives at the very center of each spool. The gears that form the inside-outside tracks are quite clever too, as are the worm-gear-driven takeup reel and output tensioner. We also appreciated the gate used to load the spool carriers into the track.

We can recall a couple of braiding machines before, including this one made entirely from Lego Technics.

Continue reading “3D Printed Machine Shows How Braiding Is Done” →

Supercon 2022: [Liz McFarland] Builds Golden Wings, Shows You How

June 13, 2023 by 7 Comments

Are you, by any chance, wondering about giving yourself wings? You should listen to [Liz McFarland] sharing her experience building a Wonder Woman suit, and not just any – the Golden Eagle suit from Wonder Woman 1984, adorned with a giant pair of wings. If a suit like that is in your plans, you’ll be warmly welcomed at a cosplay convention – and [Liz] had her sights on the San Diego Comic Con. With an ambitious goal of participating in the Comic Con’s cosplay contest, the suit had to be impressive – and impressive, it indeed was, not just for its looks, but for its mechanics too.

[Liz] tells us everything – from producing the wings and painting them, to keeping them attached to the body while distributing the weight, and of course, things like on-venue nuances and safety with regards to other participants. The dark side of cosplay building reality isn’t hidden either – talking, of course, about the art of staying within a reasonably tight budget. This build takes advantage of a hackerspace that [Liz] is an active member in – the [Crash Space] in LA. Everything is in – lasercutting, 3D printing, and even custom jigs for bending wing-structual PVC pipes play a role.

It would have been a travesty to not have the wings move at will, of course, and [Liz] had all the skills you could want for making the wings complete. She went for two linear actuators, walking us through the mechanical calculations and considerations required to have everything fit together. It’s not easy to build a set of wings on its own, let alone one that moves and doesn’t crumble as you use it – if you have already attempted bringing mechanical creations like this into life, you can see the value in what [Liz] shares with us, and if you haven’t yet delved into it, this video will help you avoid quite a few pitfalls while setting an example you can absolutely reach.

The suit was a resounding success at the con, and got [Liz] some well-earned awards – today, the suit’s story is here for the hackers’ world. Now, your cosplay aspirations have an inspiring real-life journey to borrow from, and we thank [Liz] for sharing it with us.

Continue reading “Supercon 2022: [Liz McFarland] Builds Golden Wings, Shows You How” →

Easy Graphene Production With A Laser Engraver

May 20, 2023 by 13 Comments

Graphene isn’t easy to produce at scale. But making small batches of graphene is doable in a few ways. [Robert Murray-Smith] decided to try producing “flash graphene.” This requires a big capacitor bank that is moderately expensive, so he decided to explain a different technique he read about using an ordinary laser cutter. Check it out in the video below.

We were a little disappointed that he didn’t actually make any graphene this time. He has, however, used other methods in other videos to create some type of graphene. In fact, he has many similar videos going back quite a ways as well as applications with concrete, capacitors, and more. We understand that this method doesn’t produce monolayer graphene, but actually creates a graphene “foam” with interesting properties. [Robert] talks about recent papers that show you can grow graphene on things other than Kapton tape using this method.

Continue reading “Easy Graphene Production With A Laser Engraver” →

Hackaday Podcast 219: Lots Of Lasers, Heaps Of Ham Radio, And Breaching The Blood Brain Barrier

May 19, 2023 by No comments

Elliot and Dan teamed up for the podcast this week, bringing you the week’s sweetest hacks. And news too, as the ESA performed a little percussive maintenance on a Jupiter-bound space probe, and we learned about how to get an Orwellian free TV that exacts quite a price. We talked about Bitcoin mining two ways, including a way to put all that waste heat to good use — just don’t expect it to make good financial sense. Why would you stuff zip ties into a hot glue gun? It might just help with plastic repair. Lugging a tube transmitter up a mountain doesn’t sound like a good idea, but with the right design, it’s a lot of fun — and maybe you’ll be better able to tap into Schumann resonances while you’re up there.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download a long series of ones and zeroes that, when appropriately interpreted, sound like two people talking about nerdy stuff!

Where to Follow Hackaday Podcast

Places to follow Hackaday podcasts:

Continue reading “Hackaday Podcast 219: Lots Of Lasers, Heaps Of Ham Radio, And Breaching The Blood Brain Barrier” →