Commodore Datassette Does Barbershop Quartet

October 20, 2023 by Kristina Panos 3 Comments

Okay, now this is just plain fun. [Linus Åkesson] modified a Commodore Datassette player to move its “mouth” and, when quadrupled, sing a clever barbershop tune called “Sweet End of Line” that’s a play on “Sweet Adeline“, a top hit from the summer of 1903.

What? Let us explain. Those with Commodore 64s who lacked disk drives often had the Datassette — a magnetic storage tape device, or cassette player used to load and save files. But they couldn’t open the doors themselves with a keypress, and they certainly couldn’t sing barbershop.

First off, [Linus] redirected the current that drives the magnetizing tape head through a speaker coil instead. Then he replaced the motor with a servo that opens the lid from the inside. A simple rubber band pulls the lid back shut. Software-wise, [Linus] is using a timer interrupt to run code that toggles the output signal, the rate of which determines the pitch.

Don’t worry — all of these modifications are reversible, so no Datassettes were truly harmed in the making. Don’t forget to check out the brief build/demo video after the break.

We’ve seen our share of tape players, but we’d never seen one with a crank until recently.

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Spooky Noise Box Plays War Drums

September 20, 2023 by Kristina Panos 6 Comments

What do you have cooked up to scare trick-or-treaters this Halloween? We humbly suggest adding in some type of noise box, especially one like this offering from [Paisley Computer] that uses reverb and other effects to achieve chilling, thrilling sounds.

As you can see, this instrument is essentially a bunch of doodads affixed to and through a cigar box. And as you’ll hear in the first video after the break, the various rubber bands make great drum sounds. The springs are nice, too, but our personal favorite has to be the head massager thing. Shhhing!

Inside the box you’ll find a guitar jack and some piezos glued to the underside of the top surface, but you’ll also find springs mounted across the inside that add to the resonance of the cigar box.

You can use either an interface and DAW or an effects pedal chain to really make things freaky, and [Paisley Computer] does a showdown between Focusrite interface versus various stomp pedals in the second video. In the third video, we learn how to make one of our own.

Do you like the idea of a spring reverb? How about a really big one that sounds sort of Satanic?

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Rubber Bands And O-Rings Give 3D Prints Some Stretch

February 26, 2023 by Donald Papp 9 Comments

Sometimes it would be helpful if a 3D printed object could stretch & bend. Flexible filament like TPU is one option, but [NagyBig] designed a simple bracelet to ask: how about embedding rubber bands or o-rings into the print itself?

Embedding objects into prints usually involves hardware like fasteners or magnets, but this is the first one (we can think of) that uses rubber bands. Though we have seen rubber bracelets running on printed wheels, and o-rings used to provide tension on a tool holder.

The end result is slightly reminiscent of embedding 3D printed shapes into tulle in order to create fantastic, armor-like flexible creations. But using rubber bands means the result is stretchy and compliant to a degree we haven’t previously seen. Keep it in mind the next time you’re trying to solve a tricky design problem; an embedded o-ring or rubber band might just do the trick.

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Printed Propeller Blades Repair Indoor Flyer

December 9, 2022 by Tom Nardi 5 Comments

Fair warning for readers with a weak stomach, the video below graphically depicts an innocent rubber band airplane being obliterated in mid-air by a smug high-tech RC helicopter. It’s a shocking display of airborne class warfare, but the story does have a happy ending, as [Concrete Dog] was able to repair his old school flyer with some very modern technology: a set of 3D printed propeller blades.

Now under normal circumstances, 3D printed propellers are a dicey prospect. To avoid being torn apart by the incredible rotational forces they will be subjected to, they generally need to be bulked up to the point that they become too heavy, and performance suffers. The stepped outer surface of the printed blade doesn’t help, either.

But in a lightweight aircraft powered by a rubber band, obviously things are a bit more relaxed. The thin blades [Concrete Dog] produced on his Prusa Mini appear to be just a layer or two thick, and were printed flat on the bed. He then attached them to the side of a jar using Kapton tape, and put them in the oven to anneal for about 10 minutes. This not only strengthened the printed blades, but put a permanent curve into them.

The results demonstrated at the end of the video are quite impressive. [Concrete Dog] says the new blades actually outperform the originals aluminum blades, so he’s has to trim the plane out again for the increased thrust. Hopefully the extra performance will help his spindly bird avoid future aerial altercations.

On the electrically powered side of things, folks have been trying to 3D print airplane and quadcopter propellers for almost as long as desktop 3D printers have been on the market. With modern materials and high-resolution printers the idea is more practical than ever, though it’s noted they don’t suffer crashes very well.

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Rubber Band Behemoth Winds Its Way Toward World Record

October 6, 2022 by Ryan Flowers 25 Comments

Egged on by adoring fans who demanded more aircraft videos, [ProjectAir] has decided to break the world record for rubber band powered aircraft… despite having never built a rubber band powered aircraft. Why rubber band power?

Before little two stroke motors became affordable, and long before electric motors and batteries were remotely possible, there weren’t a lot of options for powering your model aircraft. One technology that really took off was that of rubber band power. By winding a rubber band, it could store enough energy to turn a propeller for a short duration. With a 10 foot model taking the current world record, as you can see in the video below the break [ProjectAir] decided to see if he could beat it.

Rubber Band Powered Free Flight c1915 By Unknown author –

Starting with a successful free flight aircraft made of foam board, [ProjectAir] simply scaled it up to an eleven foot wing- one foot larger than the ten foot world record holder. Since there were now eight rubber band motors, a mechanism was created to release the propellers in sync, but this was problematic. Eventually a slightly heavy but solid solution was found.

[ProjectAir] did more testing, more problem solving, and through rapid iterations, he eventually was able to have a successful flight under radio control. His personal goal of a 12 second flight was exceeded, and then Guinness called! They’re interested in certifying his attempt as long as his plane can fly for at least 30 seconds- almost double his current ability. What will he do? Check the video, too, for [ProjectAir]’s challenge to the community to join him in trying to beat the world record. Sounds like fun!

Aside from powering world record attempting radio controlled aircraft, did you know that you can build a rubber band powered refrigerator? It’s true!

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Record-Setting Jumper Tosses Biomimicry Out The Window

June 29, 2022 by Ryan Flowers 39 Comments

How can a few grams of battery, geared motor, and some nifty materials get a jumping robot over 30 meters into the air? It wasn’t by copying a grasshopper, kangaroo, or an easily scared kitty. How was it done, then?

It’s been observed that of all the things that are possible in nature, out of all the wonderful mechanisms, fluid and aerodynamics, and chemistry, there’s one thing that is so far undiscovered in a living thing: continuous rotation. Yes, that’s right, the simple act of going roundy-round is unique to mechanical devices rather than biological organisms. And when it comes to jumping robots, biomimicry can only go so far.

With this distinct mechanical advantage in mind, [Elliot Hawkes] of the University of California Santa Barbara decided to look beyond biomimicry. As explained in the paper in Nature and demonstrated in the video below the break, the jumping robot being considered uses rubber bands, carbon fiber bows, and commodity items such as a geared motor and LiPo batteries to essentially wind up the spring mechanism and then, like a trap being sprung, release the pent up energy all at once. The result? The little jumper can go almost 100 feet into the air. Be sure to check it out!

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Flight Of The Pterothopter: A Jurassic-Inspired Ornithopter

April 6, 2021 by Zach Zeman 14 Comments

Ornithopters look silly. They look like something that shouldn’t work. An airplane with no propeller and wings that go flappy-flappy? No way that thing is going to fly. There are, however, a multitude of hobbyists, researchers, and birds who would heartily disagree with that sentiment, because ornithopters do fly. And they are almost mesmerizing to watch when they do it, which is just one reason we love [Hobi Cerdas]’s build of the Pterothopter, a rubber band-powered ornithopter modeled after a pterodactyl.

All joking aside, the science and research behind ornithopters and, relatedly, how living organisms fly is fascinating in itself — which is why [Lewin Day] wrote that article about how bees manage to become airborne. We can lose hours reading about this stuff and watching videos of prototypes. While most models we can currently build are not as efficient as their propeller-powered counterparts, the potential of evolutionarily-perfected flying mechanisms is endlessly intriguing. That alone is enough to fuel builds like this for years to come.

As you can see in the video below, [Hobi Cerdas] went through his own research and development process as he got his Pterothopter to soar. The model proved too nose-heavy in its maiden flight, but that’s nothing a little raising of the tail section and a quick field decapitation couldn’t resolve. After a more successful second flight, he swapped in a thinner rubber band and modified the wing’s leading edge for more thrust. This allowed the tiny balsa dinosaur to really take off, flying long enough to have some very close encounters with buildings and trees.

For those of you already itching to build your own Pterothopter, the plans come from the Summer 2017 issue of Flapping Wings, the official newsletter of the Ornithopter Society (an organization we’re so happy to learn about today). You can also find more in-depth ornithopter build logs to help you get started. And, honestly, there’s no reason to limit yourself to uncontrolled flight; we’ve come across some very impressive RC ornithopters in the past.

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