Commodore SX-64 Keyboard Upgraded From Trash To Treasure

June 30, 2020 by Kristina Panos 6 Comments

Released in 1984, the Commodore SX-64 Executive Computer was one of the first ~~portable~~ luggable color computers. It cost twice as much as a Commodore 64, had a tiny 5″ diagonal screen, and couldn’t actually support both 5¼” drives as advertised. On the upside, people say it had a slightly better keyboard than its classic cousin.

[Drygol] agreed to restore the keyboard from a friend’s Commodore SX-64 sight-unseen, and boy was this thing in bad shape. Most people would probably consider the condition a shame and write it off as a lost cause, since two of the corners were missing most of their plastic. But [Drygol] isn’t most people. [Drygol] had mad restoration skills to begin with, and this project honed them to a razor’s edge.

Plenty of the other vintage computer restorations [Drygol] has done required plastic welding, which uses heat or a lot of friction to smooth over cracks. Some of those have not stood the test of time, so he’s now in the habit of stabilizing cracks with brass mesh before filling them with fiberglass putty.

The best part is how [Drygol] managed to rebuild the corners using the same methods, soldering the brass mesh at the 90° joins, and reinforcing them with thick copper wire before beginning the painstaking putty/sand/putty process. The use of blank copper clad boards as straight edges and thickness gauges is genius.

There’s a whole lot to learn here, and the adventure beings with something that probably keeps a lot of people from trying stuff like this in the first place: how do you safely remove the badges?

You’re right, plastic welding is awesome. There even used to be a toy plastic welder. But there’s no need to troll the electronic auction bay to give it a try — just use a cheap soldering iron.

Steampunk Brushless Motor Demo Pushes All The Maker Buttons

May 29, 2020 by Dan Maloney 46 Comments

We’ll be honest right up front: there’s nothing new in [David Cambridge]’s brushless motor and controller build. If you’re looking for earth-shattering innovation, you’d best look elsewhere. But if you enjoy an aimless use of just about every technique and material in the hacker’s toolkit employed with extreme craftsmanship, then this might be for you. And Nixies — he’s got Nixies in there too.

[David]’s build started out as a personal exploration of brushless motors and how they work. Some 3D-printed parts, a single coil of wire, and a magnetic reed switch resulted in a simple pulse motor that performed surprisingly well. This morphed into a six-coil motor with Hall-effect sensors and a homebrew controller. This is where [David] pulled out all the stops on tools — a lathe, a plasma cutter, a welder, a milling machine, and a nice selection of woodworking tools went into making parts for the final motor as well as an enclosure for the project. And because he hadn’t checked off quite all the boxes yet, [David] decided to use the 3D-printed frame as a pattern for casting one from aluminum.

The finished motor, with a redesigned rotor to deal better with eddy currents, joined the wood and metal enclosure along with a Nixie tube tachometer and etched brass control plates. It’s a great look for a project that’s clearly a labor of self-edification and skill-building, and we love it. We’ve seen other BLDC demonstrators before, but few that look as good as this one does.

Continue reading “Steampunk Brushless Motor Demo Pushes All The Maker Buttons” →

Brass And Nickel Work Together In This Magnetostrictive Earphone

May 21, 2020 by Dan Maloney 24 Comments

When you go by a handle like [Simplifier], you’ve made a mission statement about your projects: that you’ll take complex processes and boil them down to their essence. So tackling the rebuilding of the humble speaker, a device he himself admits is “both simplified and optimized already,” would seem a bit off-topic. But as it turns out, the principle of magnetostriction can make the lowly speaker even simpler.

Most of us are familiar with the operation of a speaker. A powerful magnet sits at the center of a coil of wire, which is attached to a thin diaphragm. Current passing through the coil builds a magnetic field that moves the diaphragm, creating sound waves. Magnetostriction, on the other hand, is the phenomenon whereby ferromagnetic materials change shape in a magnetic field. To take advantage of this, [Simplifier] wound a coil of fine copper wire around a paper form, through which a nickel ~~TIG electrode~~ welding filler rod is passed. The nickel rod is anchored on one end and fixed to a thin brass disc on the other. Passing a current through the coil causes the rod to change length, vibrating the disc to make sound. Give it a listen in the video below; it sounds pretty good, and we love the old-time look of the turned oak handpiece and brass accouterments.

You may recall [Simplifier]’s recent attempt at a carbon rod microphone; while that worked well enough, it was unable to drive this earphone directly. If you need to understand a little more about magnetostriction, [Ben Krasnow] explained its use in anti-theft tags a couple of years back.

Continue reading “Brass And Nickel Work Together In This Magnetostrictive Earphone” →

Bolts, Brass, And Machining Chops Make Up This Tiny Combination Safe

March 10, 2020 by Dan Maloney 8 Comments

Another day, another video that seriously makes us doubt whether eschewing the purchase of a lathe in favor of feeding the family is a value proposition. This time, [Maker B] shows us what the queen of machine tools can do by turning a couple of bolts into a miniature safe.

We’ll state right up front that this build doesn’t source all its material from a single bolt. It’s more like two bolts and a few odd pieces of brass, but that doesn’t detract from the final product one bit. [Maker B] relieves the two chunky stainless steel bolts of their hex heads and their threads on the lathe, forming two nesting cylinders with a satisfyingly tight fit. A brass bar is machined into a key that fits between slots cut in the nesting cylinders, while discs of brass form the combination dials. Each disc is stamped around its circumference with the 26 letters of the alphabet; we thought the jig used for stamping was exceptionally clever, and resulted in neat impressions. The combination, which is set by placing a pin next to a letter in each disc, protects the admittedly limited contents of the tiny safe, but functionality is hardly the point. This is all about craftsmanship and machining skills, and we love it.

If you’ve sensed an uptick in resource-constrained builds like this lately, you’re not alone. The “one bolt challenge” has resulted in this wonderfully machined combination lock, as well as the artistry of this one-bolt sculpture. We’re all in favor of keeping the trend going. Continue reading “Bolts, Brass, And Machining Chops Make Up This Tiny Combination Safe” →

Single Bolt Transformed Into A Work Of Art

March 1, 2020 by Dan Maloney 24 Comments

Every once in a while, this job helps you to discover something new and completely fascinating that has little to do with hacking but is worth sharing nonetheless. Turning a single brass bolt into a beautiful Cupid’s bow is certainly one of those times.

Watching [Pablo Cimadevila] work in the video below is a real treat, on par with a Clickspring build for craftsmanship and production values. His goal is to use a largish brass bolt as the sole source of material for a charming little objet d’art, which he achieves mainly with the use of simple hand tools. The stave of the bow is cut from the flattened shank of the bolt with a jeweler’s saw, with the bolt head left as a display stand. The offcuts are melted down and drawn out into wire for both the bowstring and the shaft of the arrow, a process that’s fascinating in its own right. The heart-shaped arrowhead and the faces of the bolt head are bedazzled with rubies; the technique [Pablo] uses to create settings for the stones is worth the price of admission alone. The complete video below is well worth a watch, but if you don’t have the twelve minutes to spare, a condensed GIF is available.

[Pablo]’s artistry reminds us a bit of this not-quite-one-bolt combination lock. We love the constraint of sourcing all a project’s materials from a single object, and we really appreciate the craftsmanship that goes into builds like these.

Continue reading “Single Bolt Transformed Into A Work Of Art” →

Bend It Like Bhoite: Circuit Sculptures Shatter The Bounds Of Flatland

December 27, 2019 by Dan Maloney 5 Comments

As electronics hobbyists, we live in a somewhat two-dimensional world. Our craft is so centered around the printed circuit board that our design tools are specifically geared to spit out files tailored to the board house, who can then ship us a study in fiberglass and copper. We daub on flux and solder, add components, apply heat, and like magic, our circuits come to life, all within a few millimeters above and below the PCB.

Breaking out of this self-imposed Flatland can be therapeutic. At least that’s how Mohit Bhoite sees his free-form circuit sculptures, which he spoke about at length at the Hackaday Superconference this year. By way of disclosure, I have to admit to being a longtime fan of Mohit’s work, both at his day job as a designer at Particle, and with his spare time hobby of creating sculptures from electronic components and brass wire which can be followed on his Twitter feed. He ended up joining us for a circuit sculpture Hack Chat just before heading to Supercon, too, so not only was I looking forward to meeting him, I was sure his talk would reveal the secrets of his art and give me the inspiration to start doing some of my own. I wasn’t disappointed on either score.

Continue reading “Bend It Like Bhoite: Circuit Sculptures Shatter The Bounds Of Flatland” →

Are You Getting Your Money’s Worth From Threaded Inserts?

December 12, 2019 by Dan Maloney 14 Comments

Have you ever wondered whether it’s worth the time and expense to install threaded inserts into your 3D-printed projects? [Stefan] from CNC Kitchen did, and decided to answer the question once and for all, with science.

If this sounds familiar, it’s with good reason: we covered [Stefan]’s last stab at assessing threaded inserts back in March. Then, he was primarily interested in determining if threaded inserts are better than threads cut or printed directly into parts. The current work is concerned with the relative value of different designs of threaded inserts. He looked at three different styles of press-in inserts, ranging in price from pennies apiece to a princely 25 cents. The complexity of the outside knurling seems not to be correlated with the price; the inserts with opposed helical knurls seem like they’d be harder to manufacture than the ones with simple barbs on the outside of the barrel, but cost less. And in fact, the mid-price insert outperformed the expensive one in pull-out tests. Surprisingly, the cheapest inserts were actually far worse at pull-out resistance than printing undersized holes and threading an M3 screw directly into the plastic.

[Stefan] also looked at torque resistance, and found no substantial difference between the three insert types. Indeed, none of the inserts proved to be the weak point, as the failure mode of all the torque tests was the M3 bolt itself. This didn’t hold with the bolt threaded directly into the plastic, of course; any insert is better than none for torque resistance.

We enjoyed seeing [Stefan]’s tests, and appreciate the data that can help us be informed consumers. [John] over at Project Farm does similar head-to-head tests, like this test of different epoxy adhesives.

Continue reading “Are You Getting Your Money’s Worth From Threaded Inserts?” →