Automatic Flag Waver Lets You Show Your Loyalty Without Getting Tired

October 16, 2022 by Robin Kearey 31 Comments

A flag is a great tool to show your loyalty to a country, a sports team or even a philosophical movement. But there’s not so much you can actually do with a flag: you can either hang it somewhere, or wave it around to attact others to your cause. [Mellow] found that waving quickly becomes tiresome, and decided to design a machine that automates this task for him.

Now there’s a bit more involved in designing a proper flag-waver than simply moving the flag back and forth. Ideally, the fabric should flow smoothly from side to side and show both sides equally, in the same way a human would do when waving a big flag around. After a bit of research [Mellow] decided on a design that generates a rather complex motion using just a single servo: the mast is tilted from left to right, while gravity ensures the flag rotates around its axis. It’s probably best demonstrated visually, as [Mellow] does in the video embedded below.

The flag-waving mechanism is designed in Fusion 360 and 3D printed using white filament. Inside a little square box is a Wemos D1 Mini, powered by a lithium battery scavenged from a vape pen, as well as a battery management system and a power switch. The servo sits on top of the box and holds the flag in a little socket that allows the mast to rotate freely. [Mellow] also went one step further and built a two-flag waver, which still uses only one servo but creates two opposite motions through a set of spur gears. Both waver types bring a lively atmosphere to their surroundings, and we can actually imagine them being useful in places like sports bars.

Automatic flag-wavers are still rare devices, and as far as we can tell this is only the second one we’ve seen, after this hat-mounted example. That is, if you don’t count the automatic “flag” on this mailbox.

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A 3D Printed Ratchet That Can Really Take The Torque

October 15, 2022 by Donald Papp 5 Comments

Printed tools aren’t exactly known for their durability, but [Gladius] shows us that with some thoughtful design, it’s possible to print a ratcheting wrench that can handle surprising amounts of torque.

Look closely, and you can see that the parts are almost entirely made up of perimeters (click to enlarge).

This particular wrench is inspired by NASA’s 3D printed ratcheting wrench, and also from an early 1900s design. It sports a 1/2 inch square socket into which modern adapters can be fitted, allowing those steel parts to do their job while the wrench itself delivers the muscle.

[Gladius] found that the strongest results came from slicing parts — especially the handle — so that they come out consisting almost entirely of perimeters, with virtually no traditional infill. Want to know more? There’s a discussion on reddit where [Gladius] goes into added detail about measurements and performance.

Over the years, we’ve seen our share of powerful prints. For example, what the Crimson Axlef*cker can do looks downright intimidating. Speaking of printing things that move, we want to remind you about this handy tip for easily and reliably joining motor shafts to printed parts by (mis)using jaw couplings.

Organizational Inspiration From The Discount Tool Company

October 15, 2022 by Bryan Cockfield 13 Comments

When in need of any tool to get a job done quickly, or only for a small number of times, it’s great to have a local “discount tool” company locally for some working, yet often low-quality solution to whatever problem might arise. While there are some gems, most of these tools won’t last through heavy, sustained use like their more expensive counterparts will. On the other hand, there are other things to be had at these discount shops, such as inspiration for tackling a storage problem.

This particular storage system comes from Harbor Freight, and uses a set linked crosshairs, the center of which is hollowed out. A set of movable compartments sits on top with feet that can interlock inside the crosshairs. This allows much more efficient use of space within the toolboxes, but [Alan] wanted it to be useful for more that that. He designed and implemented the Storage Case Base Template (SCBT) which allows for a container of any size to be fitted with a similar crosshair network.

With this non-proprietary system implemented and printed, the original goal of reducing the clutter in [Alan]’s workspace was accomplished. The 3D printing files can be modified easily for any space, and are available both on Thingiverse and Printables. For some other ways of packing a lot into a small space, we featured this tiny workshop a while back that’s packed with storage hacks.

3D Printed Sorter Separates Spare Hex Nuts With A Shake

October 13, 2022 by Donald Papp 14 Comments

Got a pile of mixed hex nuts? Sort them in no time by printing [jonafriendj]’s nut sorter, which has options for pretty much any nut size you’d be after (it’s labeled metric, but actually includes Imperial sizes as well.)

Something to admire about the design is the handy little raised labels on each of the sieves, and the fact that all the parts print entirely without supports. Designing a part to play to a manufacturing method’s strengths (and avoid its weaknesses) is good DFM, or Design for Manufacturing.

With 3D printing being the boon that it is to workshops and hobbyists everywhere, it certainly pays to strive for good DFM, especially for designs meant to be shared with others. Sometimes good DFM takes a page from other manufacturing methods like injection molding, and we end up with things like using crush ribs on printed parts.

Want to see a demonstration of [jonafriendj]’s nut sorting design? Check out the short video embedded below the page break. If that leaves you wanting, take a look at a motorized, automated DIY solution.

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A Raspberry Pi Phone For The Modern Era

October 10, 2022 by Bryan Cockfield 43 Comments

While it might seem like mobile phones are special devices, both in their ease of use and in their ubiquity in the modern culture, they are essentially nothing more than small form-factor computers with an extra radio and a few specific pieces of software to run. In theory, as long as you can find that software (and you pay for a service plan of some sort) you can get any computer to work as a phone. So naturally, the Raspberry Pi was turned into one.

[asherdundas], the phone’s creator, actually found a prior build based around the Raspberry Pi before starting this one. The problem was that it was built nearly a decade ago, and hadn’t been updated since. This build brings some modernization to the antiquated Pi phone, and starts with a 3D printed case. It also houses a touchscreen and a GSM antenna to connect to the cell network. With some other odds and ends, like a speaker and microphone, plus a battery and the software to tie it all together, a modern functional Raspberry Pi phone was created, with some extra details available on the project page.

The phone has the expected features — including calling, texting, and even a camera. A small WiFi USB dongle allows it to connect to the Internet too, allowing it to do all of the internet browsing a modern smartphone might want to do. The only thing that it might be pretty difficult to do is install Android apps, and although there are ways to get Android apps working in Linux, it’s not always strictly necessary to have this functionality.

Seven Segments, But Not As We Know Them

October 6, 2022 by Donald Papp 11 Comments

We’ve seen a lot of clever re-imagining of the classic 7-segment display, and proving there is still room for something new is [Jack]’s 7-segment “DigiTag” display.

This 3D printable device has a frame into which is slotted three sliders. These sliders can be adjusted individually, mixing and matching the visibility of colored and uncolored areas, to create digits 0-9. We’ve seen some unusual 7-segment-inspired displays before, using from one motor for the whole digit to ones that need one motor per segment, but nothing quite like this approach.

While this particular design relies on the user to manually “dial in” each digit, the resulting key-like assembly (and unique shape for each digit) seems like it could have some interesting applications — a puzzle box design comes to mind.

If you have any ideas of your own on how this could be used, don’t keep them to yourself! Let us know in the comments, below.

Casting Metal With A Microwave And Vacuum Cleaner

September 29, 2022 by Bryan Cockfield 38 Comments

Metalworking might conjure images of large furnaces powered by coal, wood, or electricity, with molten metal sloshing around and visible in its crucible. But metalworking from home doesn’t need to use anything more fancy than a microwave, at least according to [Denny] a.k.a. [Shake the Future]. He has a number of metalworking tools designed to melt metal using a microwave, and in this video he uses them to make a usable aluminum pencil with a graphite core.

Before getting to the microwave kiln, the pencil mold needs to be prepared. A 3D-printed pencil is first created with the graphite core, and then [Denny] uses a plaster of Paris mixture to create the mold for the pencil. The 3D printed plastic is left inside the mold and placed in the first microwave kiln, which is turned on just enough to melt the plastic out of the mold, leaving behind the graphite core. From there a second kiln goes into the microwave to melt the aluminum.

Once the molten aluminum is ready, it is removed from the kiln and poured in the still-warm pencil mold. This is where [Denny] has another trick up his sleeve. He’s using a household vacuum cleaner to suck the metal into place before it cools, creating a rudimentary but effective vacuum forming machine. The result is a working pencil, at least after he wears down a few razor blades attempting to sharpen the metal pencil. For more information about how [Denny] makes these microwave kilns, take a look at some of his earlier projects.

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