Inconsistent layer heights in a 3D print

An Easy Fix For Inconsistent Layers In Cheap 3D Printers

If there’s one thing you can say about [Stefan] from CNC Kitchen, it’s that he’s methodical when he’s working on an improvement to his 3D printing processes, or when he’s chasing down a problem with a printer. Case in point: this root-cause analysis of extrusion inconsistencies with an entry-level 3D printer.

The printer in question is a Cetus MK3, a printer that found its way onto many benches due to its ridiculously low price and high-quality linear bearings. Unfortunately, there’s still a lot to be desired about the printer, and its tendency for inconsistent layers was chief among [Stefan]’s gripes. Such “blubbiness” can be pinned on any number of problems, but rather than guess, [Stefan] went through a systematic process of elimination to find the root cause. We won’t spoil the ending, but suffice it to say that the problem was subtle, and could probably be the cause of similar problems with other printers. The fix was also easy, and completely mechanical — just a couple of parts to replace. The video below shows the whole diagnosis process, as well as the before and after comparisons. [Stefan] also teases an upcoming treatment on how he converted the Cetus from the stock proprietary control board, which we’re interested in seeing.

If you haven’t checked out any of [Stefan]’s other 3D printing videos, you really should take a look. Whether it’s vibration damping with a concrete paver, salt annealing prints for strength, or using finite element analysis to optimize infills, he’s always got an interesting take on 3D printing.

Continue reading “An Easy Fix For Inconsistent Layers In Cheap 3D Printers”

A stepper-powered flip clock

Steppers And ESP32 Make This Retro-Modern Flip-Clock Tick

Before LEDs became cheap enough to be ubiquitous, flip-card displays were about the only way to get a digital clock. These entirely electromechanical devices had their own charm, and they have a certain retro cachet these days. Apart from yard sales and thrift stores, though, they’re a bit hard to source — unless you roll your own, of course.

Granted, [David Huang]’s ESP32-based flip clock is worlds apart from the flip cards of the “I Got You, Babe” era. Unfortunately, the video below is all we have to go on to get the story behind this clock, but it’s pretty self-explanatory. [David] started the build by making the flip cards themselves, a process that takes some topological tricks as well as a laser cutter. 3D-printed spools are loaded with the cards, which are then attached to frames that hold a stepper motor and a Hall-effect sensor. The ESP32 drives the steppers via L298N H-bridge drivers, but it’s hard to say if there’s an RTC chip or if the microcontroller is just getting time via an NTP server.

[David] might not be the only one trying to recapture that retro look, but we’ve got to hand it to him — it’s a great look, and it takes a clever maker to not only build a clock like this, but to make a video that explains it all so clearly without a single word of narration.

Continue reading “Steppers And ESP32 Make This Retro-Modern Flip-Clock Tick”

Minimalist Robot Arm Really Stacks Up

There’s nothing like a little weekend project, especially one that ends up better than you expected. And when you literally build a robotic arm out of workshop scraps, so much the better.

Longtime readers will no doubt recognize the build style used here as that of [Norbert Heinz], aka “Homofaciens” on YouTube. [Norbert] has a way of making trash do his bidding, and has shown us all kinds of seemingly impossible feats of mechatronics with just what’s lying around. In this case, his robot arm is made from scrap wooden roofing battens, or what we’d call furring strips here in the US. The softwood isn’t something you’d think would make a great material for building robots, but [Norbert] makes its characteristics work for him, like using wax-lubricated holes for hinge points. Steppers and lead screws cannibalized from an old CNC build, along with the drive electronics, provide the motion. It’s a bit — compliant — but precise enough to pick up nuts and stack them nicely. The video below gives an overview of the build, and detailed instructions are available too.

We always appreciated [Norbert]’s minimalist builds, and seeing what can be accomplished with almost nothing is always inspirational. If you’re not familiar with his work, check out his cardboard and paperclip CNC plotter, his tin can encoders, or his plasma-powered printer.

Continue reading “Minimalist Robot Arm Really Stacks Up”

Home Automation For Fans Of Quick-and-Dirty Solutions

At Hackaday, we celebrate all kinds of projects, but we’ll have to admit that the polished and professional-looking builds tend to catch our eye a lot more than perhaps they should. There’s plenty of love to be had for the rougher builds, though, of which this quick-and-dirty home automation system is a perfect example.

Before anyone rushes to state the obvious with, “Should have used some relays,” consider that [MAKE_IT_WITH_ME]’s stated goal was to get the basics of a home automation system built with pretty much nothing but what can be found in one of those Arduino starter kits. And further, consider that landlords might not look kindly on tenants who wire a bunch of SSRs or Sonoff switches into the walls of their building. So this minimalist build is perfect for certain use cases. Its interface to the building’s electrical system is 100% mechanical, via a servo that travels along the bank of switches on a stepper-driven leadscrew. The servo has a modified horn to properly flick the rocker-style switches, and although changing from switch to switch is a bit slow, it works surprisingly well. The video below shows it in action.

While we can see it possibly working as-is for Decora-style switches that are seen in some markets, we’d think some mods would be in order for the more standard toggle-style switch — perhaps a finger extending out from the horn, along with a second servo to tilt the whole assembly away from the wall to allow it to clear the switch bats.

Continue reading “Home Automation For Fans Of Quick-and-Dirty Solutions”

Rock-A-Bye Baby, On The Mechatronic Crib Shaker

While an engineering mindset is a valuable tool most of the time, there are some situations where it just seems to be a bad fit. Solving problems within the family unit would seem to be one such area, but then again, this self-rocking mechatronic crib seems to be just the cure for sleepytime woes.

From the look of [Peter]’s creation, this has less of a rocking motion and more of a gentle back-and-forth swaying. Its purpose is plainly evident to anyone who has ever had to rock a child to sleep: putting a little gentle motion into the mix can help settle down a restless infant pretty quickly. Keeping the right rhythm can be a problem, though, as can endurance when a particularly truculent toddler is fighting the urge to sleep. [Peter]’s solution is a frame of aluminum extrusion with some nice linear bearings oriented across the short axis of the crib, which sits atop the whole thing.

A recirculating ball lead screw — nothing but the best for [Junior] — and a stepper drive the crib back and forth. [Peter] took care to mechanically isolate the drivetrain from the bed, and with the selection of the drive electronics and power supply, to make sure that noise would be minimal. Although thinking about it, we’ve been lulled to sleep by the whining steppers of our 3D printer more than once. Or perhaps it was the fumes.

Hats off to [Peter] for a setup that’s sure to win back a little of the new parent’s most precious and elusive commodity: sleep.

CNC Scroll Saw Add-On Cuts Beautiful Wooden Spirals

If there’s one thing that woodworkers have always been good at, it’s coming up with clever jigs and work-holding solutions. Most jigs, however, are considerably simpler and more static than this CNC-controlled scroll saw add-on that makes cool wooden spirals a snap.

As interesting as the products of this setup are, what we like about this is the obvious care and craftsmanship [rschoenm] put into making what amounts to a hybrid between a scroll saw and a lathe. Scroll saws are normally used to make narrow-kerf cuts in thin, delicate materials, often with complicated designs using very tight radius turns. In this case, though, stock is held between centers on the lathe-like carriage. The jig uses a linear slide driven by a stepper and a lead screw to translate the workpiece perpendicular to the scroll saw blade while a geared headstock rotates it. Starting with the blade inserted into a through-hole, the saw slowly cuts a beautiful nested spiral down the length of the workpiece. An Uno, a GRBL shield, and some stepper drivers let a little G-code control the two axes of the jig.

The video below shows it in action; things do get a bit wobbly as the cut progresses, but in general the jig works wonderfully and results in some lovely pieces. At first we thought these would purely be objets d’art, but then we thought about this compression screw grinder for DIY injection molding machines and realized these wooden screws look pretty similar.

Continue reading “CNC Scroll Saw Add-On Cuts Beautiful Wooden Spirals”

Clock-of-Clocks Adds Light-Pipe Hands For Beauty And Function

We’ve gotten used to seeing “meta clocks,” clocks that use an array of analog clock faces and piece together characters using the hands of the clocks. They’re very clever, and we always like to see them, especially when they come with detailed build instructions like this one does.

What’s also nice about [Erich Styger]’s “MetaClockClock” display is the twist on the original concept. Where most clock-of-clocks depend on the contrast between the hands and the faces of the analog movements, [Erich] added light to the mix. Hidden inside the bezel of each clock is a strip of RGB LEDs; coupled with the clear acrylic hands of the clock, which act as light pipes, each clock can contribute different shapes of different colors to the display. Each clock is built around a dual-shaft stepper motor of the kind used in car dashboard gauges; the motors each live on a custom PCB, while the LEDs are mounted on a ring-shaped PCB of their own. Twenty-four of the clocks are mounted in a very nice walnut panel, which works really well with the light-pipe hands. The video below shows just some of the display possibilities.

[Erich] has documented his build process in extreme detail, and has all the design files up on GitHub. We won’t say that recreating his build will be easy — there are a lot of skills needed here, from electronics to woodworking — but at least all the information is there. We think this is a beautiful upgrade to [Erich]’s earlier version, and we’d love to see more of these built.

Continue reading “Clock-of-Clocks Adds Light-Pipe Hands For Beauty And Function”