3D Printed Earth Clock Is Cute Replica Of Our Delicate Planet

May 22, 2021 by Lewin Day 10 Comments

Plenty of clocks around us are useful for telling us the precise hour, minute, and second of the day. However, few can give us an intuitive sense of how far away we are from the enveloping cloak of night. This 3D printed Earth clock built by [Simon Rob] promises to do just that.

The build consists of an Arduino Nano driving a stepper motor, which turns a 3D printed model of the Earth through 360 degrees each day. The Earth is rotated within a black shroud such that the current portion of the Earth seeing sunlight is the visible section on the clock, while the rest is hidden from view. There’s a three-stage planetary gear reduction which turns a date wheel connected to the black shroud so that the clock remains accurate throughout the year. The gear ratio isn’t perfect — [Simon] calculates its drift to be 20 hours over a year -but it’s close enough for the clock’s given purpose of being a cool thing.

The clock looks great, and a lot of that is down to [Simon]’s careful work painting the Earth to match the real thing based on Google’s satellite maps. Incidentally it’s not the first Earth clock we’ve seen, either. We might just have to get building one for our own coffee table at home. Video after the break.

Continue reading “3D Printed Earth Clock Is Cute Replica Of Our Delicate Planet” →

Lithophane Lamp Has Us Over The Moon

May 21, 2021 by Lewin Day 7 Comments

Lithophanes are artistic creations which rely on the varying thickness of a material that is then backlit to reveal an image. While these were often made in porcelain in the past, these days we have the benefit of 3D printing on our side. The principle can be deftly applied to everything from flat planes to spheres, with [Tiffany Lo] demonstrating a great application of the latter with her 3D printed moon lamp.

The basic concept is to take a 2D image of the lunar surface, and then use it to generate a height mapped sphere for 3D printing. When lit from within, the sphere will appear as per the surface of the moon. The sphere geometry was generated with the Lithophane Sphere Maker online tool combined with NASA data of the moon intended for computer graphics purposes. The sphere was then printed on a typical FDM printer before being assembled upon a base with LEDs inside for backlighting.

The result is an attractive moon lamp that both recalls the heavy rock that follows us in a tidally-locked orbit, and yet can be switched off at night to make it easier to sleep. Unfortunately, it’s impractical to turn off the shine from the real moon, and we suspect nobody is working on the problem.

We’ve seen other moon lamps before; they’re a great starting point because the moon’s greyscale tones work well as a lithograph. More advanced techniques are likely necessary for those eager to create lamps of the gas giants; if you’ve done so, be sure to drop us a line.

3D Printing Omni-Balls For Robot Locomotion

May 20, 2021 by Lewin Day 6 Comments

Wheels are all well and good for getting around, but they only tend to rotate about a single axis. Omni-wheels exist, but they’re still a little too pedestrian for [James Bruton]. His latest project involved 3D printing custom omni-balls which roll in all directions. (Video, embedded below.)

The omniball concept comes from earlier work by Osaka University, which also produced a treaded tank-like vehicle by the name OmniCrawler as well. The spherical design, fitted with an axle and casters as well, allows rotation in multiple directions, allowing for a platform fitted with such omni-balls to easily rotate and translate in all directions.

[James] set about creating his own version of the design, which relies on grippy TPU filament for grip pads to give the 3D printed hemispheres some much needed grip. There’s also bearings inside to allow for the relative rotation between the hemispheres and the internal castor, necessary to allow the wheels to move smoothly when sitting on either pole of the hemispheres. Skate bearings were then used to assemble three of the omni-balls onto a single platform, which demonstrated the ability of the balls to roll smoothly in all directions.

While it’s just a demonstration of the basic idea for now, we can imagine these balls being used to great effect for a robot platform that needs to navigate in tight spaces on smooth surfaces with ease. The mechanical complexity of the omni-balls probably negates their effective use in dirtier offroad contexts, however.

We’ve seen [James]’s work before too – such as his compliant leg design for walking robots, and his active gyroscope balancer last week. When does [James] sleep?

Continue reading “3D Printing Omni-Balls For Robot Locomotion” →

Toolchanging Printers Get A Nozzle Hanky Like No Other

May 18, 2021 by Sonya Vasquez 7 Comments

When it comes to toolchanging 3D printers, idle nozzles tend to drool. Cleaning out that nozzle goo, though, is critical before switching them into use. And since switching nozzles can happen hundreds of times per print, having a rock-solid cleaning solution is key to making crisp clean parts. [Kevin Mardirossian] wasn’t too thrilled with the existing solutions for cleaning, so he developed the Pebble Wiper, a production worthy nozzle wicking widget that’s wicked away nozzles thousands of times flawlessly.

With a little inspiration from [BigBrain3D’s] retractable purge mechanism, [Kevin] is first purging tools onto a brass brad. Rather than have filament extrude into free space, it collects into a small bloblike “pebble” that cools quickly into a controlled shape. From here, after one quick flick with a servo arm and a small wipe with a silicone basting brush, the nozzle is ready to use. The setup might sound simple, but it’s the result of thousands and thousands of tests with the goal of letting no residual ooze attach itself to the actual part being printed. And that’s after [Kevin] put the time into scratch-building his own toolchanging 3D printer to test it on first. Finally, he’s kindly made the files available online on Github for other hackers’ tinkering and mischief.

So how well does it work? Judging by the results he’s shared, we think spectacularly. Since adopting it, he’s dropped any sacrificial printing artefacts on the bed entirely and been able to consistently pull off stunning multimaterial prints flawlessly with no signs of residual nozzle drool. While toolchanging systems have been great platforms for hacking and exploration, [Kevin’s] Pebble Wiper takes these machines one step closer at hitting “production-level” of reliability that minimizes waste. And who knows? Maybe all those pebbles can be sized to be ground up, remade into filament, and respooled back into usable filament?

Continue reading “Toolchanging Printers Get A Nozzle Hanky Like No Other” →

Putting 3D Printed Chain Through Its Paces

May 15, 2021 by Lewin Day 15 Comments

One of the more frustrating things facing makers in decades past was the problem of power transmission. Finding things like belts, pulleys, sprockets, and chain for your projects could be difficult, particularly if you lived far from the shipping radius of suppliers like McMaster-Carr. These days, there’s no need to fuss, because you can simply 3D print whatever you need, as [Let’s Print] demonstrates by whipping up some chains.

The chains are a mixed design, combining plastic inner and outer links with bolts and nuts to fasten them together. [Let’s Print] tries out several combinations of ABS, PLA, and PETG, running them on 3D printed sprockets and determining that they are all functional, albeit at minimum load. The chains are also put through tensile testing by attaching a heavy brake disc to a length of chain and dropping the weight to see at which point the chains snap.

We’d love to see more 3D-printed chains; all-plastic snap-together designs, or even those that print pre-assembled are particularly tantalizing ideas. We’d also enjoy more testing done with the chain under some proper torque loads, rather than just spinning freely.

We’ve seen work from [Let’s Print] before, too – in the case of this awesome water pump. Video after the break.

Continue reading “Putting 3D Printed Chain Through Its Paces” →

A Stackable Planetary Gearbox You Can Print At Home

May 14, 2021 by Lewin Day No comments

In one little corner of YouTube is a small but vibrant community sharing videos about gearboxes of their own design, particularly those with very high ratios or other quirky features. Adherents of the subculture are known as gearheads, and [Let’s Print] is among them. His latest creation is a 3D printed planetary gearbox design with a focus on easy assembly and versatile ratio choice. (Video, embedded below.)

The gearbox came about as [Let’s Print] grew weary of designing bespoke geartrains for each of their individual projects. The planetary design they landed on has the benefit of being stackable, with each reduction block fitted adding a 1:3 stepdown to the train.

For testing purposes, four stages were ganged up for a total reduction ratio of 1:81. The resulting gearbox was able to lift 40 kg before its output coupler failed, no mean feat for some plastic squirted out of a hot nozzle. It’s a common problem with huge ratio gearboxes made out of plastic – often, the very components of the gearbox can’t hold up to the huge loads generated.

Regardless of the limitations of the material, we’re sure the gearbox will prove useful in future projects from [Let’s Print]. We’ve seen other tough 3D printed gearbox builds before too, such as this anvil-lifter from the aptly-named [Gear Down For What]. Dive into the online gearbox subculture yourself.

Continue reading “A Stackable Planetary Gearbox You Can Print At Home” →

3D Printing Restores Bandsaw

May 13, 2021 by Al Williams 24 Comments

A great addition to a home shop is a bandsaw, but when [Design Prototype Test] got a well-used one, he found it wasn’t in very good shape. The previous owner put in an underpowered motor and made some modifications to accommodate the odd-sized blade. Luckily, 3D printing allowed him to restore the old saw to good working order.

There were several 3D printed additions. A pulley, a strain relief, and even an emergency stop switch. Honestly, none of this stuff was something you couldn’t buy, but as he points out, it was cheaper and faster than shipping things in from China. He did wind up replacing the initial pulley with a commercial variant and he explains why.

Continue reading “3D Printing Restores Bandsaw” →