Printable One-Way Driver Skips Ratchet For A Clutch

Ratcheting screwdrivers can help you work faster, even if their bulk means they’re not the best option for working in tight spaces. [ukman] decided to build a similar device of his own, relying on a slightly different mechanism — an overrunning clutch.

The design is similar to a freewheel used on a bicycle, allowing free movement in one direction while resisting it in the other. As the screwdriver is turned in one direction, the shaft is wedged by a series of cylinders that lock it in place. However, the geometric shape of the clutch allows the shaft to turn in the other direction without getting wedged in place. The result is a screwdriver that can be turned, rolled back, and turned further. Thus, screws can be tightened without loosening one’s grip on the tool.

With its 3D printed construction, it’s probably not the best tool for heavy-duty, high-torque jobs, but it looks more than capable of handling simple assembly tasks. We’ve seen some other nifty screwdrivers around these parts, too.

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Frequency Counter Restoration Impeded By Kittens

We think of digital displays as something you see on relatively modern gear. But some old gear had things like nixies or numitrons to get cool-looking retro digital displays. The HP 521A frequency counter, though, uses four columns of ten discrete neon bulbs to make a decidedly low-tech but effective digital display. [Usagi Electric] has been restoring one of these for some time, but there was a gap between the second and third videos as his workshop became a kitten nursery. You can see the last video below.

In previous videos, he had most of the device working, but there were still some odd behavior. This video shows the final steps to success. One thing that was interesting  is that since each of the four columns are identical, it was possible to compare readings from one decade to another.

However, in the end, it turned out that the neon bulbs were highly corroded, and replacing all the neon bulbs made things work better. However, the self-check that should read the 60 Hz line frequency was reading 72 Hz, so it needed a realignment. But that was relatively easy with a pot accessible from the back panel. If you want to see more details about the repair, be sure to check out the earlier videos.

We love this old gear and how clever designers did so much with what we consider so little. We hate to encourage your potential addiction, but we’ve given advice on how to acquire old gear before. If you want to see what was possible before WS2812 panels, you could build this neon bulb contraption.

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Ryobi Battery Hack Keeps CPAP Running Quietly

When it comes to cordless power tools, color is an important brand selection criterion. There’s Milwaukee red, for the rich people, the black and yellow of DeWalt, and Makita has a sort of teal thing going on. But when you see that painful shade of fluorescent green, you know you’ve got one of the wide range of bargain tools and accessories that only Ryobi can offer.

Like many of us, Redditor [Grunthos503] had a few junked Ryobi tools lying about, and managed to cobble together this battery-powered inverter for light-duty applications. The build started with a broken Ryobi charger, whose main feature was a fairly large case once relieved of its defunct guts, plus an existing socket for 18-volt battery packs. Added to that was a small Ryobi inverter, which normally plugs into the Ryobi battery pack and converts the 18 VDC to 120 VAC. Sadly, though, the inverter fan is loud, and the battery socket is sketchy. But with a little case modding and a liberal amount of hot glue, the inverter found a new home inside the charger case, with a new, quieter fan and even an XT60 connector for non-brand batteries.

It’s a simple hack, but one that [Grunthos503] may really need someday, as it’s intended to run a CPAP machine in case of a power outage — hence the need for a fan that’s quiet enough to sleep with. And it’s a pretty good hack — we honestly had to look twice to see what was done here. Maybe it was just the green plastic dazzling us. Although maybe we’re too hard on Ryobi — after all, they are pretty hackable.

Thanks to [Risu no Kairu] for the tip on this one.

Building A Spot Welder From 500 Junk Capacitors

[Kasyan TV] over on YouTube was given a pile of spare parts in reasonably large quantities, some of which were useful and allocated to specific projects, but given the given the kind of electronics they’re interested in, they couldn’t find a use for a bag of 500 or so low specification 470uF capacitors. These were not low ESR types, nor high capacitance, so unsuitable for power supply use individually. But, what about stacking them all in parallel? (video, embedded below) After a few quick calculations [Kasyan] determined that the total capacitance of all 500 should be around 0.23 Farads with an ESR of around 0.4 to 0.5 mΩ at 16V and packing a theoretical energy total of about 30 joules. That is enough to pack a punch in the right situation.

A PCB was constructed to wire 168 of the little cans in parallel, with hefty wide traces, reinforced with multiple strands of 1.8mm diameter copper wire and a big thick layer of solder over the top. Three such PCBs were wired in parallel with the same copper wire, in order to keep the total resistance as low as possible. Such a thing has a few practical uses, since the super low measured ESR of 0.6mΩ and large capacitance makes it ideal for smoothing power supplies in many applications, but could it be used to make a spot welder? Well, yes and no. When combined with one of the those cheap Chinese ‘spot welder’ controllers, it does indeed produce some welds on a LiPo cell with a thin nickel plated battery strip, but blows straight through it with little penetration. [Kasyan] found that the capacitor bank could be used in parallel with a decent LiPo cell giving a potentially ideal combination — a huge initial punch from the capacitors to blow through the strip and get the weld started and the LiPo following through with a lower (but still huge) current for a little longer to assist with the penetration into the battery terminal, finishing off the weld.

[Kaysan] goes into some measurements of the peak current delivery and the profile thereof, showing that even a pile of pretty mundane parts can, with a little care, be turned into something useful. How does such an assembly compare with a single supercapacitor? We talked about supercaps and LiPo batteries a little while ago, which was an interesting discussion, and in case you’re still interested, graphene-based hybrid supercapacitors are a thing too!

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The Tools To Fight Against Single-Use Plastic

Imagine for a moment that you design products for a living. But you can’t design all the things, so you have to buy some of your stuff from big-box stores just to go about your everyday life. This is more or less what happened to [Eric Strebel], who recently bought a bathroom faucet from IKEA. This particular flat-pack faucet came with a single-use plastic nut driver to be used in putting the faucet together. Since there is no marking that indicates the plastic type, it can’t be easily recycled. Not even the size of the business end is indicated. So between the shoddy plastic construction and the lack of information, most people are going to just throw this thing away. And that’s terrible.

So what’s to be done? Aside from boycotting IKEA (which [Eric] may do in the future for all we know), there’s not much to do but to offer up solutions on public platform and see what happens. To that end, [Eric] came up with five different ways of making this nut driver that are arguably more sustainable than single-use mystery plastic.

Say what you will about sustainability of using metals, which have to be mined, versus plastic – many of these methods use no tooling, so that’s something. Nut drivers made by [Eric] would instead be laser-cut from flat stock and either folded up and welded, or assembled from a multi-piece cut into a single-piece tool via perpendicular members that slot together. Or as [Eric] points out, the design could stay exactly the same as the plastic original and be die-cast instead.

It’s certainly an interesting exercise in design, and it’s really cool to see a little bit into [Eric]’s thought process when it comes to improving existing things. Be sure to check it out after the break, and let us know how you’d have done it better.

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Angled Drill Guide Helps You With Those Tricky Holes

If you’ve ever tried to drill a hole on an angle with a power drill, you’ve probably drilled some pretty shocking holes. To do it right, you really need some mechanical assistance, and this jig from [Kartik_Nandrui] should do the trick.

The device uses a guide that sits on the surface to be drilled, with a pair of angled connectors that fit two wooden dowels. These connect the guide to a corresponding sleeve that fits around the drill body. The sleeve then slides up and down the dowels, allowing the drill to move in a straight line towards the targeted area.

It’s a useful hack, but we can see room for some improvements that would take it to the next level. Having a way to lock the angle of the guide base would be great for accuracy. As it’s 3D printed, it would also be simple to create a version with a curved guide base that could fit over pipes, or other designs to fit complex geometries like roof sheeting or other corrugated materials.

Sometimes the most interesting hacks are the ones that get us thinking about our own potential projects. If you’ve got any creative tool hacks you’ve been brewing up in the lab, be sure to let us know!

A Particularly Polished ATX Bench Power Supply

Let’s be real, yanking the ATX power supply out of an old desktop computer and turning it into something you can use on the workbench isn’t exactly an advanced project. In fact, you could probably argue it’s one of the first DIY builds a budding electronic hobbyist should tackle — after all, you’re going to need a reliable bench supply if you want to do any serious work anyway.

But of course, there’s a big difference between doing the minimum and really giving something your all, and we think this ATX bench supply from [Steve Thone] of The Neverending Projects List is a phenomenal example of the latter. It not only looks impressive, but it’s been tricked out with plenty of bells and whistles to make it as capable as possible. What was once a basic 230 watt PSU pulled from an old Dell is now a piece of gear that any hacker or maker would love to have in their collection. Continue reading “A Particularly Polished ATX Bench Power Supply”