Category Archives: Don’t Try This At Home

Maker gives his dad remote-controlled eyebrows

This project will raise some brows…

When you have a pair of formidable eyebrows like Alec Smecher’s father, it can probably get a bit tiring always having to raise them by yourself. What if there was a remote-control feature that could take of that for you? Well, this is exactly what the Maker decided to do as a birthday gift for his dad.


The simple circuit consists of an ATmega328 that runs a few 6V motors in response to IR signals, an L293D quad H-bridge for the power switching to the motor and a VS838 infrared receiver, all mounted to an old Petzl headlamp. Smecher then attached sewing bobbins to the motor spindles, and wound some thread around them.


“The eyebrows are attached by taping the thread to the skin just underneath — right above the eyelids — using a piece of band-aid adhesive. A little piece of toothpick tied to the end of the string helps prevent it from slipping out of the band-aid,” Smecher explains.

Okay, that’s enough writing. You gotta see the ‘brows in action below!

Create your own smart heater for $15

Just in time for winter, this Maker added smart temperature control to his infrared heater. 

The IoT refers to the idea that things, in this case an infrared heater, can be connected to the Internet. Although at times this may seem like overkill, in this case, it seems like a very practical solution. As creator Yuvaltz puts it, “Both IR heaters I have at home have only two power levels. Without any control, it’s easy to get to either a too hot or a not hot enough situation.” Naturally the Arduino-compatible and Wi-Fi-enabled Cactus Micro (ATmega32U4) was used to take his heater into the 21st century!


The Cactus module controls a relay, which turns the heater on when appropriate. The control scheme is based on something called a proportional-integral-derivitave (PID) loop, which allows for several factors to be taken into account when deciding on the appropriate heater state.

Since the Cactus is Wi-Fi-enabled, temperature variation as well as power output can be uploaded to a website. Yuvaltz setup a ThingSpeak channel for this device, and was able to generate two very interesting plots. One comparing the temperature data gleaned from two sensors that he tried, while the other plotted the temperature as well as how much power the heater put out at a certain time.


As Yuvaltz notes, don’t try something like this unless you’re familiar with high-voltage safety. A simple remote control is suggested as an alternative, but perhaps even that could be hacked for PID control! Check out his entire build here.

Humans can now be bioluminescent with this LED implant

The Northstar V1 is the latest device biohackers are implanting under their skin.

There are wearables… and then there are embeddables. The latter is technology you can’t necessarily take off because it’s implanted in your body under the skin. This seems extreme for most people, but not for a group biohackers who recently implanted a coin-sized LED device in their hands.


The Northstar V1 is the latest subdermal technology implant created by Grindhouse Wetware, a Pittsburgh-based collective comprised of biohackers and grinders. For those unfamiliar with the term, grinders are people who are part human, part machine and they share the mission of “augmenting humanity using safe, affordable, open source technology.”

The Northstar is a module with five red LEDs that light up for 10 seconds when activated by a magnet, illuminating the user’s skin. While a light up implantable doesn’t sound too appealing and worth cutting up your hand for, co-founder Tim Cannon says the Northstar is designed to show that things can be inserted safely and be usable under the skin.


The Northstar is coated with Parylene, which is employed in biotech to prevent the body’s rejection of the device. At the heart of it is an ATmega28P. A limitation to the unit, however, is its power. The implant runs on a CR2325 lithium coin cell and is not rechargeable. However, the Grindhouse team believes this simple gadget will pave the way for a more advance and functional Northstar V2 that will be rechargeable, have gesture recognition, Bluetooth capabilities and even deliver biometric data.

At the moment, V1 is purely for aesthetic purposes and has gained interest from the body modification community as a way to backlight body art. If you’re interested in becoming a cyborg, visit Cannon and the Grindhouse Wetware’s website.

[Images: Ryan O’Shea/Grindhouse Wetware]

Build a $200 laser engraver with Arduino

This DIY machine can engrave designs into wood, opaque plastic and leather.

Many people have a nice assortment of tools in their garage or Makerspace, but once you get into computer-controlled implements, both your capabilities and, normally, the price of them goes up a notch. Instructables user Macinblack20 decided to step into the world of laser engravers with his project, and according to his how-to article, it can be built for less than $200.


His machine uses an Arduino Uno (ATmega328) running grbl, an open source CNC controller, to actuate two stepper motors. They move a one Watt laser in the X and Y axes on a gantry made out of OpenBuilds components. These parts, as well as a few others, are listed in the “materials” portion of his Instructables page. OpenBuilds appears to be an interesting option for Makers trying to source mechanical parts that can be hard to find or expensive.


Admittedly, employing a laser meant for engraving can be hazardous to your eyes, so you’ll definitely need a pair of laser safety glasses meant for the type of beam you’re using. Although an interesting build, don’t attempt something like this unless you’re absolutely confident that you can be safe with it.


For a seemingly less hazardous build, you may want to check out the CNC EtchABot, an Etch A Sketch with knob controls as well as an automatic erasing mechanism.

This machine can chop veggies like a pro

Simone Giertz is back — this time with a machine that can chop broccoli, lettuce, tomatoes, carrots, zucchini, cucumbers and just about anything.

Already equipped with several quirky machines that take care of most of her morning routine (from getting out of bed to brushing her teeth to feeding her breakfast), the innovative and always hilarious Simone Giertz has taken her ingenuity to the next part of the day: lunch.


That’s because the Maker, who happens to be a lifelong vegetarian, has developed a terrifyingly awesome Chopping Machine. And like her other inventions, the gadget was designed to automate a particular task that would otherwise require spending time and effort.

Why, you ask? “Because I’m lazy (?),” Giertz says. “I’ve spent a significant amount of time chopping, mincing and dicing all varieties of vegetables. Eating healthy is boring enough in itself, why does preparing healthy food have to be such a tedium?”


The Chopping Machine is exactly what it sounds like: a mechanism that can literally chop veggies. It consists of an Actobotics system, two knives and a pair of servo motors, all driven by an Arduino Nano (ATmega328).

The device itself is relatively simple, yet pretty dangerous nevertheless. (Translation: don’t try this at home!) Two servo motors lift the knife up and a spring at the bottom pulls it right back down. With it, Giertz can now slice broccoli, lettuce, tomatoes, carrots, zucchini, cucumbers and pretty much anything else… even the board itself.

Intrigued? Terrified? Fascinated? See it for yourself below!



Maker creates tiny RC flamethrower

A tiny radio-controlled flamethrower… what can go wrong?

It goes without saying that nothing good can come of a tiny radio-controlled flame thrower, so it’s probably not the best idea to build one. Yet, we couldn’t help but share a recent project from “MAKE-log,” who has done just that.


Admittedly, its creator does warn operating the 13cm x 4cm x 8cm device at your own risk. The RC Flamethrower is fueled by a 35ml deodorant spray. A micro servo pushes down the can’s lever and actuates its valve, while a SparkFun Spark Gap Igniter (no longer available) helps generate the spark and deterministically spit out flames.

The remote is in the form of a Microsoft joystick, which is equipped with an an MCU, an RF transmitter and an LED to denote that radio transmission is taking place.


Meanwhile, the flamethrower itself is based on an ATmega328P and features a transceiver, a DC/DC boost converter for supplying 5V, two Li-ion 11mAh batteries in parallel, a pair of 5-bit RGBs and a Li-ion charger set to 300A. The SparkFun igniter is connected directly to the the Li-ion battery via MOSFET.

That all said, MAKE-log’s compact build does boast several safety interlocks and dons an informative interface. A 128 x 64 OLED display shows the flamethrower’s burn time and remaining battery levels, while a two LEDs and a mini 5V buzzer emit visual and audible warnings for the user. Red indicates fire mode, flashing blue lights suggest a loss of signal.

YOU SHOULD NOT recreate this on your own. We repeat, you SHOULD NOT recreate this on your own. However, MAKE-log provides a detailed breakdown of the build below, and shares the AVR-GCC code for the joystick here.

Don’t try this at home: A knife-wielding tentacle

Now, who wants to take a ‘stab’ at turning this off? 

While some Makers like to think outside the box, others prefer to mount a servo-driven tentacle to a box. In what may surely be one of the most abstract (and dangerous) DIY gadgets of all-time, YouTuber “OutaSpaceMan” has developed a mechanism that flails a Swiss Army knife around in the air.


We all know what you’re wondering, why a knife bot? According to his video description, he built the device “to amuse those who may be bored. Just right now I think the world needs a laugh.”

The aptly named littleBits Arduino Knife-Wielding Tentacle consists of an Arduino Mega (ATmega2560), a littleBits Proto Module and a servo motor, which together create a mechanical arm that randomly slashes and stabs through the air. Meanwhile, the project is running the Blink Without Delay Arduino sketch.

Okay, so now the better question: How the heck do you turn this thing off? Kids, don’t try this at home.