This week on Maker Update, levitating water with LEDs, 3D printed skull buttons, servos on Pi, a game of Twang, Arduino animatronics, and project talk with Becky Stern. This week’s Cool Tool is the EBL 18650 Rechargeable Battery.

Show Notes

Project of the Week

RGB Time Fountain by Isaac Chasteau
https://blog.arduino.cc/2018/02/19/levitate-water-drops-with-rgb-leds-and-arduino/
https://github.com/isaac879/RGB-Time-Fountain

More Projects

Skull Buttons by mikeasaurus
https://www.instructables.com/id/Skull-Buttons/

Cool Tools Minute

EBL 18650 3.7V 3000mAh Li-ion Rechargeable Batteries
https://www.amazon.com/exec/obidos/ASIN/B00DNPT1D6/ctmakerupdate-20

Charger
https://www.amazon.com/exec/obidos/ASIN/B01MR2JJ1W/ctmakerupdate-20

Holders
https://www.amazon.com/exec/obidos/ASIN/B013DUOJV4/ctmakerupdate-20

Tools/Tips

Hackspace Issue #4
https://hackspace.raspberrypi.org/issues

Basic Servo Use With the Raspberry Pi and GpioZero
https://www.raspberrypi-spy.co.uk/2018/02/basic-servo-use-with-the-raspberry-pi/

Twang Joystick by Bart Dring
https://github.com/Critters/TWANG

Twang Kit on Tindie
https://www.tindie.com/products/33366583/twang-shield-kit/

Jim’s Guide to Arduino Animatronics
https://youtu.be/8oh_uvJ9mG4
https://youtu.be/Cm8dbQKGaRU

Becky Talks To Me About Her Arduino Social Stats Tracker
https://youtu.be/vscEXCqtoEk

Maker Faires This Weekend

Dubai Mini Maker Faire Dubai
Thalia Mini Maker Faire Nürnberg
Palm Bay Mini Maker Faire Palm Bay, Florida
Denton Mini Maker Faire Denton, Texas
Kalispell Mini Maker Faire Kalispell, Montana
Windsor-Essex Mini Maker Faire Windsor, Ontario
Gainesville Mini Maker Faire Gainesville, Florida

Transcript

This week on Maker Update, levitating water with LEDs, 3D printed skull buttons, the maker’s rechargeable battery, servos on Pi, a game of Twang, Arduino animatronics, and project talk with Becky Stern.

I’m Donald Bell, and it’s time for another Maker Update. I hope you’re all doing well. I’ve been keeping busy welding up this new go kart frame in the spare little pockets of time I have. It’s starting to look like a thing though, which is exciting.

There’s lots to talk about today, so let’s get started with the project of the week.

This week, the Arduino blog introduced me to Isaac Chasteau, who created this amazing water fountain where the drops look like they’re levitating or even floating up.

The project uses a peristaltic pump to continuously move the water from the bottom to the top. A 3D printed funnel narrows the stream down a little and there’s a metal scouring pad at the bottom to cut down on the sound.

The magic of the project though, are these LED strips on the side of the fountain which are set to strobe at just the right frequency to capture the phase of the water dropping, creating the illusion.

Set a little slower, the water looks like it’s dropping in slow motion. A little higher, and the drops appear to float upwards. You can also have colors each phase at a different rate to create cool effects.

An Arduino Uno is driving the LEDs, using code and a custom library that Isaac has over on GitHub. You can find all the link in the show notes.

Another project that caught my eye this week were these 3D printed skull buttons by Mikeasaurus. The button itself is adorable, and looks great printed out on this bone-colored filament.

But what’s extra great is how accessible the project is. Mike goes step-by-step through how he measured his original button and created this design in Tinkercad, in addition to a bunch of prototypes that didn’t quite work out.

Of course, it doesn’t have to be a skull. It could be whatever you want. But it’s a great intro into working in Tinkercad, and a fun, quick 3D print.

It’s time for another Cool Tool review. This time we’re taking a look at the most popular rechargeable battery most people know nothing about. This is the 18650, I got a pair of these name brand ones for $9, though you can get sketchy ones even cheaper. I’m going to show you why they’re useful and if you want some for yourself, using the Amazon link in the description helps support my videos and the Cool Tools blog.

The 18650 battery is an extremely common, Lithium Ion rechargeable battery. We just don’t normally see them because they’re tucked away inside our electronics. I opened up a rechargeable drill recently and found one inside. There’s one inside this solar emergency radio. I’m sure there are a handful of others in my house I’m not even aware of.

They’re relatively cheap, easy to recharge, and they can store a lot of power compared to rechargeable AA battery.

What makes these great for electronic projects and cosplay lighting effects is that they spit out a 3.7 volts that’s perfect for small project boards like the Teensy, Adafruit Trinket, Gemma, Feather. And it turns out to also be a good enough voltage for driving LED strip.

So for example, I wanted to put some LEDs on my Power Racer to show it off at night. I glued in some strip, and wired it up to Gemma board. And to power it, I first used one of these flat Li-Po packs, but it didn’t hold much charge, and when it runs out I either had to recharge it through the board over USB, or swap it out by pulling this tiny connection. It wasn’t worth it.

As an alternative, I also tried running it off AA batteries, which were easier to swap out, but drained just as fast.

So far, using a single 18650 has worked the best. I bought a 10-pack of these holders on Amazon for around $7, wired one up and glued it in. With this, it runs for longer than I need, and a loop of gaffer tape around it makes it easy to pull out when I need to recharge.

You do need to get a special charger. This one with a nice LED display cost me $16 on Amazon. It runs off USB. You can get cheaper ones without the screen.

So that’s my story with 18650 rechargeable batteries. They’re great for powering small project boards and LEDs, which are honestly the bread and butter of most maker projects.

Like any rechargeable battery though, you have to be careful not to puncture it or expose it to fire, so be careful.

You can pick up the batteries, the holders, and the charger all using the Amazon links in the description, and remember can see thousands of reader recommended tools like these at Cool-Tools.org.

I’ve got time for a few more tips. First, be sure to check out the new issue of Hackspace magazine. It’s got Sophy Wong, maker of the Raspberry Pi Selfie bot on the cover, showing off some Neopixel fingernails. She’s also inside with a cool Ghostbusters Proton Pack. You can download a PDF of the magazine for free.

Matt from Raspberry Pi Spy has a great tutorial on how to get started using and controlling servos with the Raspberry Pi. There are sample Python scripts you can copy and paste, and a video walkthrough too.

The Twang Joystick project by Bart Dring is two years old, but it’s new to me. It’s a game you play on a single strip of LEDs, inspired by Line Wobbler by Robin B. It uses a doorstop spring as a controller and there’s a great playlist of videos showcasing how Bart developed the project and even mounted a playable version on the front of his house.

What’s new, is that he’s just started selling a kit for this project on Tindie, with a custom board for connecting up the accelerometer, a speaker, and the LED strip. It seems like a great price for what he’s made.

Jim Leemhuis, the maker behind the amazing talking tiki totem I showed you in episode 50, has a multi-part series on building an Arduino-based animatronic puppet. He’s using an Adafruit Feather and a servo FeatherWing to create a system that allows you to record and playback the movements of up to 8 servos at once.

He also shows you how to create the controls you’ll need to puppet mouth movements or eye blinks, head movement and eye movement. I love this stuff. It’s like Disney imagineering 101, and I’m excited to see more videos from Jim.

Finally, this past monday I had the chance to catch up with Becky Stern and talk to her about her Social Stats Tracker Display. It was a great talk and I learned about the cheap, awesome Node MCU boards she used for her project. You can find the video of our talk on my channel, and I’ll also link to it at the end here.

And if you ever want to catch these talks live and ask questions, be sure to hit that notification bell down by the subscribe button.

Maker Faires! Man there was a dry spell there for awhile but there are a ton happening this weekend. You’ve got Dubai, Nürnberg Germany, Palm Bay, Florida, Denton, Texas, Kalispell, Montana, Windsor, Ontario, and Gainesville, Florida. If one of those are near you, don’t miss a chance to mingle with your people and get inspired.

And that does it for this week’s show. Be sure to subscribe, leave a thumbs up, leave a comment, get on the email list, pick up some of those 18650 rechargeable batteries if you can use them. And if you really enjoyed this show, you can buy me a coffee using the Buy Me a Coffee link right down here. That’s been working great and I really appreciate it. Alright? Thanks for watching and I’ll see you next week.