This week on Maker Update, an off-world bartender, glowing sine waves, neon pixels, 3D digits, a levitating toy, hand loupes, step-down casters, micro connectors, and tapping technique.

++Show Notes [Maker Update #189]++

-=Project of the Week=-

VK-01 Off World Bartender by Donald Bell
https://www.instructables.com/id/VK-01-Off-World-Bartender/

-=More Projects=-

Sinusoidal Noise by Kai Lab
https://kailaboratory.com/sinusoidal-noise
https://www.instagram.com/p/CC8ek_xFli5/
https://www.instagram.com/p/CCTHy66FXk_/

Neon Pixels by Pierre Muth
https://hackaday.com/2020/07/23/384-neon-bulbs-become-attractive-display/
https://pierremuth.wordpress.com/2020/07/08/neon-pixel/

Mechanical 7 Segment Display By indoorgeek
https://www.instructables.com/id/Mechanical-7-Segment-Display/

Levitation, a 3D Printed Automaton Illusion by gzumwalt
https://www.instructables.com/id/Levitation-a-3D-Printed-Automaton-Illusion/

-=Tools/Tips=-

DiResta Push Stick Development
https://youtu.be/E-V2TrXMk0g

Adam Savage’s Favorite Tools: Ratchet and Socket Set!
https://www.tested.com/art/makers/909821-adam-savages-favorite-tools-ratchet-and-socket-set/

5 Common Connectors and How to Handle Them!
https://youtu.be/KfLrBR8DP8g

Touch Light Hand Loupe
https://youtu.be/z6Wl6M9lmnQ

Re-positioning casters by SeeJaneDrill
https://youtu.be/YjPzjTi-xy0

Gareth’s Tips, Tools, and Shop Tales – Issue #55
https://www.getrevue.co/profile/garethbranwyn/issues/gareth-s-tips-tools-and-shop-tales-issue-55-263941

5 Weird Tools from Izzy Swan
https://youtu.be/oJqNxjMrb2I

-=Digi-Key Spotlight=-

How to Splice and Tap Wires
https://youtu.be/evrw0ojvzz0

Transcript

This week on Maker Update, an off-world bartender, glowing sine waves, neon pixels, 3D digits, a levitating toy, hand loupes, step-down casters, micro connectors, and tapping technique.

Hey everybody, I’m Donald Bell back again with another Maker Update, the show where I update you on what makers are up to. I hope you’re all doing well and staying vigilant. It’s a tough way to spend a summer. The good news is, I have a lot of cool projects to share with you, including a project of the week that I’ve been hinting at for a long time.

I’m embarrassed to award this one to myself this week, but I hope you’ll agree that the VK-01 Off World Bartender is a worthy nominee. This is a cocktail machine that I started working out in my head in August of last year, after the Cocktail Robotics Grand Challenge. 

For this machine I wanted something with more pumps, more interaction, and something with a story to tell. I went with a Blade Runner theme. The idea is that you have to scan your off-world ID card to start it up.

You then place your cup on the platform to access the drink menu. You type in your order number on the keypad and the drink comes out, combining up to 8 ingredients.

To make it all work, I have a Pi 3B running Hello Drinkbot’s fork of the Bartendro cocktail software. It acts as a wireless server that I can send drink orders to, and it also drives all the pumps using an Adafruit DC motor hat.

I have another Pi, a less expensive model A+ running the video playlist on this 7-inch screen. This Pi uses the MP4 Museum software and plays a sequence of 5 videos triggered by the different interactions.

The interactive bits — the RFID card reader, the platform switch, and the keypad, are all connected up to small Arduino type boards that check for input and then signal the video playlist to advance.

It’s one of those projects that seemed straightforward when I was working on each piece individually, but then started to seem insane when I got around to connecting everything together.

You can find the entire build guide over on Instructables, along with every piece of code, every 3D model, and links to every component. 

Now for all the cool projects done by other people. Sinusoidal Noise by Kai Lab is an artwork that uses a grid of 98 illuminated boxes that fade in and out. 

It looks like the sort of thing you could pull off with some neopixel strip and an Arduino — and you probably could. But what makes this build so unique is that every LED is running on its own analog circuit.

The random patterns that emerge here are the result of the slight variations and imperfections of the components. There’s no code, and no math, just pure sine wave oscillations falling in and out of sync with each other. 

Whatever’s going on, it’s mesmerizing. To get a better look at the circuit and assembly, check out the Kai Lab Instagram account. Their method of using brass or copper rod as power rails to link all the lights together seems particularly ingenious. 

Another grid of lights done the hard way, Pierre Muth shows how he made this addressable grid of 384 dot-sized neon tubes. 

This time the sequencing is digital, but the light source is extremely analog. 

Each of these tiny tubes measures 6.5mm across and requires 100 volts at .5 mA to light up. 

To adapt them for digital control, Pierre designed a small batch of printed circuit boards for each tube to mount on, with an integrated chip to drive up the voltage. Those boards were then mounted onto a charlieplexed matrix and connected to an ESP32 board to drive the animations.

It’s a crazy amount of work, but I have to say, there is something kind of raw and magical about the way these look.

Keeping in the theme of displays made the hard way, check out this 7-segment mechanical display made by Indoor Geek. 

This is a mostly 3D printed design that uses handmade solenoids to push and pull each segment in and out of view.

On their Instructable, you can see how each electromagnet coil is made around a 3D printed bobbin. You’ll need one of these for each segment. 

To power it all, each of the magnets is driven by it’s own MOSFET, with some diodes to protect the circuit from spiking voltage.

Again, it’s a lot of work, but I do like that you get a little of that flip-dot mechanical noise with something like this. 

For another bit of 3D printed magic, check out Greg Zumwalt’s latest 3D automata. It’s called Levitation, and like most of his designs, nearly every part here is 3D printed, including the gearing.

Greg’s been doing a number of 3D printed illusions recently that make use of magnets, so initially I thought that was what was going on here too. 

I don’t want to spoil it for you, but see if you can figure out what’s really going on.

Now for some tips and tools. Though it’s not his normal thing, I really liked the latest video from Jimmy Diresta where he outlines his process for prototyping this table saw push stick. 

You get to see it go from a notebook sketch, to a scrap wood prototype, to a CNC cut version, and all the iterations along the way. The video includes narration from Jimmy, and it’s a great peek into his design process.

On Tested, don’t believe this video on Adam Savage’s favorite ratchet and socket set. Yes, there’s some time spent on why this set from Milwaukee stands apart from the rest, but really the video provides a fantastic rant on the sins of blow molded tool cases. 

They’re bulky, they either hold things too loose or too tight, and they often don’t make it easy to get tools and cords packed back in. Adam goes off, but then he brings it back to show some examples of blow-molded cases that get it right.

On the iFixit channel, I found this video on five common internal electronic connections to be fascinating. If you’ve ever tried to repair your own cell phone or laptop, you’ve run into this secret world of ultra-compact connectors. They’re almost like tiny mechanical puzzles, and they’re easy to break if you don’t know what to look for. This video offers a great demonstration.

On the Cool Tools channel, Sean Micahel Ragan shows off this inexpensive magnifying loupe that lights up when you touch it. If you need a well-lit, magnified look at some of those iFixit connections, this might be just the thing.

Leah from SeeJaneDrill has a video up showing how to install stepdown casters on your workbench. A set of 4 runs around $30 and can support up to 600 pounds. They look like a great addition to a workbench or tool cart that you sometimes want to move around but otherwise need to stay in place.

Speaking of foot-operated workshop hacks, in the latest issue of Gareth Branwyn’s Tips, Tools, and Shop Tales newsletter, I came across this foot-operated power switch recommended by Izzy Swan. 

He’s using it to use a drill powered chisel attachment, locking the drill switch on and turning the drill on and off with his foot using the foot switch. 

Because the switch just interrupts the power to the thing you plug into it, it could be a useful tool for all kinds of projects, even halloween props.

For this week’s Digi-Key spotlight, check out this video from a few years back on how to splice and tap wires. 

Splicing wires may be old-hat for many of us, but it’s always good to remind people what proper technique looks like.

This tapping technique kinda blew my mind though. I’m a little embarrassed to admit this, but I’ve never seen someone tap one wire into another like this before. I’m also just now realizing that this is where the surveillance term wiretapping probably comes from. 

If I’m too stupid to be on this channel, please let me know, but be gentle. My hope is to be just smart enough to stick around, but then I have moments like this where I’m not sure how I got this far in life without seeing someone tap a wire. If it’s a first for you too, I won’t tell anyone.

And that does it for this week’s show. Be sure to subscribe, leave a thumb’s up, or leave a comment. I’m happy to answer any cocktail engineering questions, or endure the humiliation of my wire tap realization. You can also get on the Maker Update email list. A big thanks to my patrons on Patreon and to Digi-Key electronics for making this show possible. Thanks for watching, and I’ll see you next week.