Pumping Concrete

Due to social distancing, gym rats throughout the world are turning everyday objects into exercise equipment to keep up the routine without actually hitting the gym. A particularly pleasing version of this are these concrete dumbbells whipped up by the unfortunately named hacker [ShitnamiTidalWave].

If you happen to have half a bag of concrete — quick set or otherwise — out in the shed you can follow the lead on this one. But even if you’re not the kind of person who has “arm day” on your calendar (most of us here in the Hackaday bunker do not) this hack is still worth your time. Mold making is one of the uber-useful skills you should have in your hacker toolkit and [ShitnamiTidalWave] has done both an excellent job of building a mold, and of explaining the process.

Raw material for this one couldn’t be easier; each mold is made out of plywood, 2×4 stud, and nails, along with handles made of 3/4″ PVC pipe. The studs were ripped down and used to create the 45 degree chamfers at each edge. Mold-making veterans will tell you that release agent is a must and in this case rubbing the insides of the molds with wax made it a snap to pry the wooden forms off of the set concrete.

Concrete has a tendency to crack as it cures so if you’re casting large pieces like this touch-sensitive concrete countertop you might want to throw in some fiber reinforcement to the mix. If you’re keen on seeing some of the more impressive mold-making skills at work, check out how metal parts are cast from 3D-printed molds and how a master duplicates parts using silicone molds.

[via r/DIY]

Put Down New Roots From Home With A Free-Form Tree Of Life

Mandalas are meditative objects that mean many things to myriad religions. Psychologist Carl Jung equated them with the concept of the Self as a whole, and put forth the notion that an urge to create mandalas signifies a period of intense personal growth.

[Sander van de Bor] took up the mandala challenge at the beginning of 2020 and decided to create several of them in free-form electronic style. If you’re looking for a healthy new way to deal, [Sander] has step-by-step instructions for making your own light-up tree of life by wrangling a wad of wires into a trunk and branches. Big bonus if you already find soldering to be soothing.

[Sander] starts by forming a circle from brass rod. This is the base for the rest of the build and will tie all the LED grounds together. The tree is twisted from a cluster of enameled copper wires that are eventually soldered together to distribute power from a coin cell out to the six SMT LEDs.

You could argue that the tree should be ground because it’s rooted to Earth, but you could also argue that the circle should be ground because the circle of life is a grounding force. Something to think about while you design and build your own, eh?

If electronic sculpture becomes your new thing, explore all the angles with the master manipulator, [Mohit Bhoite].

One Anti-Static Ring To Delight Them All

What’s the worst thing about winter? If you’re as indoorsy as we are, then static electricity is probably pretty high on the list. It can ruin your chips, true, but you always wear a wrist ground strap when you handle those, right? But away from the bench, every doorknob and light switch is lying in wait, ready to shock you. If you had an anti-static ring like [LaPuge], you could be watching a tiny neon bulb light up instead of the air between your poor finger and the discharge point.

The ring itself is printed in TPU 95A filament for comfort and flexibility. There isn’t a whole lot to the circuit, just a neon bulb, a 1MΩ resistor, and some copper tape, but this piece of functional jewelry has the potential to spark up plenty of charged conversations. Zap your way past the break to see it light up against a door handle.

If you want to light up neon bulbs all year long, build a field of them and wave them near your Tesla coil!

Continue reading “One Anti-Static Ring To Delight Them All”

Converted Car Lets Toddlers Tool Around

A few years ago, a professor at the University of Delaware started a project called Go Baby Go. It’s designed to bring fun and affordable mobility to small children with disabilities. The idea is to modify Power Wheels cars to make them easier for disabled kids to operate, and to teach as many people as possible how to do it in the process. The [South Eugene Robotics Team] is taking this a step further by replacing the steering wheel with a joystick that controls two motors with an Arduino Nano.

In the first instance you replace the foot pedal with a push button. The plans also call for a PVC frame, a high-backed seat, and a seat belt to make it safer. The end result is a fun ride the kid can control themselves that functions a lot like a power wheelchair, but is much more affordable. It has the added bonus of being a fun conversation piece for the other kids instead of a weird scary thing.

They also replace the front wheels with 5″ casters, because being able to spin around in circles is awesome. Their project shows how to do the entire conversion in great detail, starting with a standard ride-on car that comes with some assembly required. Motor past the break to check out a short demo with an extremely happy child tooling around in a fire truck.

If these kids get too wild, they’re gonna need traction control for these things.

Continue reading “Converted Car Lets Toddlers Tool Around”

Mitch Altman Asks How You’re Using Your Life

This talk will probably make you a bit angry. You might be upset with some of Mitch Altman’s views or his hyperbole in describing them. Or you might be upset because you totally agree with his views and feel the same disappointment he does with many (ab)uses of technology. Either way, the point of his talk, which was given at the 2019 Hackaday Superconference, is that we all should think deeply about what we choose to do with our time and our talents. Consider yourself challenged.

The video below is packed full of colorful ideas, along with some colorful language. Let’s take a look.

Continue reading “Mitch Altman Asks How You’re Using Your Life”

See If Today’s Air Quality Will Conch You Out

Air quality is one of those problems that is rather invisible and hard to grasp until it gets bad enough to be undeniable. By then, it may be too late to do much about it. But if more people were interested in the problem enough to monitor the air around them, there would be more innovators bringing more ideas to the table. And more attention to a problem usually means more accountability and eventual action.

This solar-powered particulate analyzer made by [rabbitcreek] is a friendly way to take the problem out of the stratosphere of ‘someday’ and bring it down to the average person’s backyard. Its modular nature makes it fairly simple to build, and the conch shell enclosure gives it a natural look. That shell also cleverly hides the electronics, while at the same time allowing air and particulates to reach the sensor. If you don’t like the shell enclosure, we think the right type of bird feeder could protect the electronics while allowing airflow.

[rabbitcreek] attached a sizeable solar panel to the shell on a GoPro mount so it can be adjusted to face the sun. The panel charges a Li-Po battery that gets boosted to 5V. Every two hours, a low-power breakout circuit wakes up the Feather ESP32 and takes a reading from the particulate sensor. [rabbitcreek] can easily see the data on his phone thanks to the Blynk app he created.

Why limit this to your yard? Bare ESP32s are cheap enough that it’s feasible to build a whole network of air quality sensors.

Printed Separator Separates Printed Pages

We all know people trapped in aging bodies who can’t do all the things they used to do. It’s easy to accept that you may never move small furniture around by yourself again, but losing the ability to do something as simple as separating the pages of your newspaper to keep reading it is an end to enjoyment.

When [Randomcitizen4] visited his grandma over the holidays, she mentioned having trouble with this, among other things. He fired up his printer and got to work designing a device to help her get back to the funny pages. This simple gripper mechanism uses rubber bands for tension and flexible filament to get a firm grip on the paper. The jaws default to the open position so they’re ready to grab some newsprint, and a light squeeze of the handles slides the top page back from the stack, creating a gap for Grandma’s fingers. You can see a demo on page 32 after the break.

Although the device does work on some books and magazines, he’d like to improve the design of the grips to make the device more universally useful. [Randomcitizen4] says he tried a few things already, but we wonder if a more complex surface pattern might do the trick — maybe less like fins and more like a tire tread pattern. All the STLs are available if you want to give it a go.

If Grandma’s newspaper ever goes out of print, she should still be able to read it on a tablet or an e-reader. Then maybe [Randomcitizen4] can build some kind of remote-controlled page turner for her.

Continue reading “Printed Separator Separates Printed Pages”