Flux And Solder Paste Dispenser Looks Good While Doing It

Syringes are pretty ergonomic, but when manually dispensing flux and solder paste it doesn’t take long before one wants a better way. [Elektroarzt]’s flux and solder paste dispenser design uses 3D-printed parts and minimal hardware (mostly M3x20 screws, and an optional spring) to improve handling and control.

The operating principle is very similar to how a hot glue gun feeds a stick of glue.

How does it work? The ratcheting lever mechanism is similar to that of a hot glue gun, where an arm slips into notches in a rod when pressed down, driving it forward and never backward. In the process, a larger lever movement is translated into a shorter plunger travel, enhancing control.

The types of syringes this tool is meant to be used with have a plunger tip or piston (the rubber stopper-looking part, in contact with the liquid) inside the loaded syringe, but no plunger shaft attached to it. This is common with syringes meant to be loaded into tools or machines, and [Elektroarzt]’s tool can be used with any such syringe in a 10 cc size.

It’s an attractive design, and we like the way syringes top-load as well as the way the tool is made to lay flat on a tabletop, with the lever pointed up.

Want truly fine-grained control over your extrusions? Then check out this dispenser which really lets one dial in small amounts. You can also go motorized, and let a small PCB and stepper motor do the work.

Print Your Own Standardized Wire Spool Storage

Hardware hackers tend to have loads of hookup wire, and that led [firstgizmo] to design a 3D printable wire and cable spool storage system. As a bonus, it’s Gridfinity-compatible!

The slot to capture loose ends is a nice touch, and the units can be assembled without external hardware.

There are a lot of little design touches we love. For example, we like the little notch into which the wire ends are held, which provides a way to secure the loose ends without any moving parts. Also, while at first glance these holders look like something that goes together with a few screws, they actually require no additional hardware and can be assembled entirely with printed parts. But should one wish to do so, [firstgizmo] has an alternate design that goes together with some M3 bolts instead.

Want to adjust something? The STEP files are included, which we always love to see because it makes modifications to the models so much more accessible. One thing that hasn’t changed over the years is that making engineering-type adjustments to STL files is awful, at best.

If there is one gotcha, it is that one must remove wire from their old spools and re-wind onto the new to use this system. However, [firstgizmo] tries to make that as easy as possible by providing two tools to make re-spooling easier: one for hand-cranking, and one for using a hand drill to do the work for you.

It’s a very thoughtful design, and as mentioned, can also be used with the Gridfinity system, which seems to open organizational floodgates in most people’s minds. Most of us are pinched for storage space, and small improvements in space-saving really, really add up.

3D Printing A Telescope Is Rewarding, Even If Not Always Cheaper

What can one expect from 3D printing an 8″ Newtonian telescope? [Molly Wakeling] shares her thoughts after doing exactly that. The performance was on par with any solid 8″ telescope, but in the end it wasn’t really any cheaper than purchasing a manufactured unit. Does that mean it wasn’t worth it? Not at all!

[Molly] makes the excellent observation that the process of printing and building one’s own telescope is highly educational and rewarding. Also, the end result is modular, user-serviceable, and customizable in a way that many commercial offerings can only dream of. It’s a great conversation starter with other enthusiasts, as well!

[Molly] printed the 203 Leavitt design (3d models available on Printables) which is an 8″ Newtonian telescope. This telescope design uses a concave parabolic mirror (a significant part of the expense) at the back of the tube to gather and focus light, and a small flat mirror near the front of the tube reflects this light to an eyepiece on the side. The wood stand makes things convenient, and we like the elastic tie-down used as a simple way to put tension on the mounts.

Do you find yourself intrigued but would prefer to start a little smaller and cheaper? Good news, because the same designer of the 203 Leavitt has a very similar design we happen to have featured before: the 114 Hadley. It features easily obtainable, lower-cost optics which perform well and can be easily ordered online, making it a great DIY starter telescope.

Print Your Next LED Bezel

LED bezels (also known as LED panel-mount holders) are great, so how about 3D printing the next ones you need? Sure, they’re inexpensive to purchase and not exactly uncommon. But we all know that when working on a project, one doesn’t always have everything one might need right at hand. At times like that, 3D printing is like a superpower.

Printing a part you find yourself short of can be a lifesaver.

[firstgizmo]’s design is made with 3D printing in mind, and most printers should be able to handle making them. Need something a little different? You’re in luck because the STEP files are provided (something we love to see), which means modifications are just a matter of opening them in your favorite CAD program.

There’s not even any need to export to an STL after making tweaks, because STEP support in slicer programs is now quite common, ever since PrusaSlicer opened that door a few years ago.

Not using 5 mm LEDs, and need some other size? No problem, [firstgizmo] also has 3 mm, 8 mm, and 10 mm versions so that it’s easy to mount those LEDs on a panel. Combined with a tool that turns SVG files into multi-color 3D models, one can even make some panels complete with color and lettering to go with those LEDs. That might be just what’s needed to bring that midnight project to the next level.

Drunken EBay Purchase Becomes Motorized, Speaking Dalek

Not every impulsive purchase on eBay leads to possession of a wooden Dalek, but when a friend did exactly that, [Tony Goacher] did his part to turn ‘Dalek Bob’ into a motorized and remote-controlled unit of impressive stature.

Fitting wheels to shafts and motors to a frame can be a bit tricky when none were made with the other in mind.

The purchased Dalek is made of wood and, with the help of two bolts, is of sufficient size to trap a human inside. There’s a bench of sorts upon which the captive can sit, and with some effort, shuffle the surrounding frame awkwardly about. The scale of the Dalek is impressive, but it was clear the effect of human-powered locomotion was lacking. The solution was to install wheelchair motors, tires, and an ESP32-based remote control.

Quite a lot of work went into mounting the motors and wheels, and the challenges will be familiar to anyone who has done hobby robotics. One can choose ideal motors and wheels, but making them fit one another can be an entirely different story. Shafts and hubs are of different sizes, motor mounting doesn’t quite match the platform, and it’s all a bit like fitting a square peg into a round hole. But with access to the right tools, it’s nothing a little metalwork and welding can’t solve.

For the control system, the ESP32 (with a beautiful CNC-routed custom PCB) sets itself up as a wireless access point that serves a web-based control panel for piloting, and controls two H-bridges to drive the motors. What’s more, it also provides a sound board from which a second operator can trigger appropriate phrases and sounds from the Dalek.

Some folks prefer their remote-controlled Daleks plush and cute instead of large and looming, but we like the smooth movement and imposing stature of this one. Watch it all in action in the video, embedded below.

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Pocket-sized Test Pattern Generator Helps Check Those CRTs

[Nicholas Murray]’s Composite Test Pattern Generator is a beautifully-made, palm-sized tool that uses an ESP32-based development board to output different test patterns in PAL/NTSC. If one is checking out old televisions or CRTs, firing up a test pattern can be a pretty handy way to see if the hardware is healthy or not.

The little white add-on you see attached to the yellow portion is a simple circuit (two resistors and an RCA jack) that allows the microcontroller to output a composite video signal. All one needs to do is power on the device, then press the large button to cycle through test patterns. A small switch on the side toggles between NTSC and PAL video formats. It’s adorable, and makes good use of the enclosures that came with the dev board and proto board.

In a pinch a hacker could use an original Raspberry Pi, because the original Pi notably included a composite video output. That feature made it trivial to output NTSC or PAL video to a compatible display. But [Nicholas]’s device has a number of significant advantages: it’s small, it’s fast, it has its own battery and integrated charger, and the little color screen mirroring the chosen test pattern is a great confirmation feature.

This is a slick little device, and it’s not [Nicholas]’s first test pattern generator. He also created a RP2040-based unit with a VGA connector, the code of which inspired a hacker’s home-grown test pattern generator that was used to service a vintage arcade machine.

Cookie Launcher Makes You Catch Your Own Snack

Holiday cookies are a joy, and to make things a bit more fun, [The Skjegg] created the Cookie Launcher. At the touch of a button, a door opens and the tin launches a cookie (and perhaps a few crumbs) skyward. Catching it is up to the operator, but since the tin can hold up to 40 cookies at once (39 in a magazine and 1 in the launcher), there’s enough to get some practice in.

The design is a real thing of beauty, from the rotary cookie holder to the ejector. Individual cookies are held in a pan-style magazine that rotates until a tasty disk is lined up with the ejector. The red separators aren’t just for show, either. The little inward protrusion on each one interacts with an optical sensor to ensure the system always knows when things are lined up.

The launcher design is pretty neat, too. There’s a platform that uses two smooth bolts as guides, and elastic bands to store energy. A motor cranks it downward, where it locks into place. The rotary magazine then turns to line up a cookie, which gravity feeds into the launcher by rolling down an incline. When a cookie is in place, a door in the lid opens and the launcher platform releases, sending the cookie skyward.

The original concept for the Cookie Launcher involved voice activation, but training the voice module to trigger on custom Norwegian commands wasn’t very reliable. Luckily, a button is far more obedient. It may be a bit less magical to use, but in our opinion the physicality of a button push meshes perfectly well with the requirement to catch your own cookie.

You can get a good look at the operation and a detailed tour of the insides in the video, embedded below. Thanks to [Rohit] for sending in the tip!

If airborne cookies aren’t your bag, check out one a very different approach to hands-free cookie dispensing.

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