Design a Coil for a Specific Inductance

YouTuber [RimstarOrg], AKA Hackaday’s own [Steven Dufresne], shows how to make a DIY inductor for a specific inductance. This is obviously a great skill to learn as sometimes your design may call for a very accurate inductance that may be otherwise hard to find.

Making your own inductor may seem daunting. You will have to answer a few questions such as: “what type of core will I use?”, “how many turns does my coil need?”, or “how do I calculate these parameters to create the specific inductance I desire?”. [RimstarOrg] goes through all of this, and even has a handy inductance calculator on his website to make it easier for you. He also provides all the formulae needed to calculate the inductance in the video below.

Using a DIY AM Radio receiver, he demonstrates in a visual way how to tune an AM Radio with a wiper on his home-built coil. Changing the inductance with a wiper changes the frequency of the radio: this is a variable inductor,

This video is great for understanding the foundations of inductors. While you may just go to a supplier and buy yours, it’s always great to know how to build your own when you can’t find a supplier, or just can’t wait.

Continue reading “Design a Coil for a Specific Inductance”

Summer Is Approaching. Are You Prepared To Relax?

[Blake Schreurs] found himself in dire straights — there was a critical lack of available hammocks in his immediate vicinity, and he wanted one. Fast. So he built a hammock stand in half an afternoon.

Initially dismayed by the cost of store-bought models, [Schreurs]’ hammock stand is perfect for woodworking-newbies and yard-loungers on a budget alike, as the build requires only a few straight cuts and some basic tools to whip up.

After cutting and laying out the lumber to make sure that it will all fit together as intended, [Schreurs] aligned and drilled holes through the pieces — don’t worry, he’s included the measurements in his post. Playing a game of connect-the-boards-with-carriage-bolts-nuts-and-washers — with a minor pause in the action to attach the feet to the base — all but finished this quick build. All that’s missing now is a hammock in which to recline!

One final note: be sure to use galvanized hardware for this — or any — project that’s expected to spend time out in the elements. Rust is not usually your friend!

Lounging in your backyard beginning to feel a little cramped? Take you relaxation on the road.

DIY Induction Soldering Iron

[Kasyan TV] shows us how to make a really simple DIY induction soldering iron complete with DIY soldering tips.

This is a pretty cool project. Most of us are used to temperature controlled ceramic heating elements, but there are other ways to get those irons up to temperature. Using scraps from older, presumably broken, soldering irons and some pieces of copper and iron along with a thermocouple for temperature management, [Kasyan TV] manages to throw together an Inductively heated soldering iron. To insulate the coil from the iron they use Kapton tape. The video goes on to show how to make your own induction iron, although missing is a power supply. We are sure a quick eBay search for an induction heater module should bring up something suitable to power the iron, or you could just wait and watch the their next video that will go over power supplies. The soldering tips are simply made from thick copper wire sculpted into the correct shape.

There are advantages to using a soldering iron like this, for example they are pretty durable and will take a knock or two, Our concern is that magnetically sensitive parts may not be happy, and the iron might destroy what you are trying to build. Either way we’ve put the video below the break, so take a look.

Hackaday has featured a few different DIY soldering irons and some pretty cool DIY Soldering Stations over the years. What is your soldering iron of choice and why?

Continue reading “DIY Induction Soldering Iron”

Practical Enclosure Design, Optimized for 3D Printing

[3D Hubs] have shared a handy guide on designing practical and 3D printing-friendly enclosures. The guide walks through the design of a two shell, two button remote control enclosure. It allows for a PCB mounted inside, exposes a USB port, and is optimized for 3D printing without painting itself into a corner in the process. [3D Hubs] uses Fusion 360 (free to hobbyists and startups) in their examples, but the design principles are easily implemented with any tool.

One of the tips is to design parts with wall thicknesses that are a multiple of the printer’s nozzle diameter. For example, a 2.4 mm wall thickness may sound a bit arbitrary at first, but it divides easily by the typical FDM nozzle diameter of 0.4 mm which makes slicing results more consistent and reliable. Most of us have at some point encountered a model where the slicer can’t quite decide how to handle a thin feature, delivering either a void between perimeters or an awkward attempt at infill, and this practice helps reduce that. Another tip is to minimize the number of sharp edges in the design, because rounded corners print more efficiently and with smoother motions from the print head.

The road to enclosures has many paths, including enclosures made from FR4 (aka PCB material) all the way down to scrap wood with toner transfer labeling, and certainly desktop 3D printing has been a boon to anyone who’s had to joylessly drill and saw away at a featureless plastic box.

Quick and Dirty Shock Gloves

[JLaservideo] has created some cool high-voltage gloves and uploaded a video on YouTube showing you how to get your mitts on a pair of your own. Using some very simple parts, he manages to make some decent sparks.

At the heart of this project is one of those new-fangled arc lighters which normally use some type of voltage multiplier circuit to function. The rest of the build is just wire, glue, aluminum foil, a switch, and paintball gloves.

Using the tip of each finger as an electrode, anything he touches will complete the circuit, creating high-voltage arcs. The demo of burning through paper is pretty neat, although we’ll admit we’re at a loss to think of what other tricks you could pull off with electrified fingertips. Anyone?

Continue reading “Quick and Dirty Shock Gloves”

The Science Behind Boost Converters

[Ludic Science] shows us the basic principles that lie behind the humble boost converter. We all take them for granted, especially when you can make your own boost converter or buy one for only a few dollars, but sometimes it’s good to get back to basics and understand exactly how things work.

The circuit in question is probably as simple as it gets when it comes to a boost converter, and is not really a practical design. However it helps visualize what is going on, and exactly how a boost converter works, using just a few parts, a screw, enameled wire, diode, capacitor and a push button installed on a board.

The video goes on to show us the science behind a boost converter, starting with adding a battery from which the inductor stores a charge in the form of an electromagnetic field. When the button is released, the magnetic field collapses, and this causes a voltage in the circuit which is then fed through a diode and charges the capacitor a little bit. If you toggle the switch fast enough the capacitor will continue to charge, and its voltage will start to rise. This then creates a larger voltage on the output than the input voltage, depending on the value of the inductor. If you were to use this design in a real life application, of course you would use a transistor to do the switching rather than a push button, it’s so much faster and you won’t get a sore finger.

This is very basic stuff,  but the video gives us a great explanation of what is happening in the circuit and why. If you liked this article, we’re sure you’ll love Hackaday’s own [Jenny List] explain everything you need to know about inductors.

(updated thanks to [Unferium] – I made a mistake about the magnetic field collapsing when the button is pressed , When in reality it’s when the button is released that this happens. Apologies for confusion.)

Continue reading “The Science Behind Boost Converters”

Manual LCD Makes Information Display Tedious, Educational

The HD44780 is one of the first chips we learned about as a kid, and chances are good you’ve used one in your project at some point, and almost certain that you’ve interacted with one in your life. The character LCD is ubiquitous, easy to interface, and very robust. They come in sizes from 8 x 1 to 20 x 4 and even larger, but they almost all have the same pinout, and there are libraries in many embedded environments for interacting with them. [The 8-Bit Guy] decided to interface with one using just switches and a button, (YouTube, embedded) with the intent of illustrating exactly how to use them, and how easy they are.

Continue reading “Manual LCD Makes Information Display Tedious, Educational”