RotBot Adds A Extra Dimension To 3D Printing, With A Twist

It always seemed to us that the Z-axis on a 3D printer, or pretty much any CNC machine for that matter, is criminally underused. To have the X- and Y-axes working together to make smooth planar motions while the Z-axis just sits there waiting for its big moment, which ends up just moving the print head and the bed another fraction of a millimeter from each other just doesn’t seem fair. Can’t the Z-axis have a little more fun?

Of course it can, and while non-planar 3D printing is nothing new, [Stefan] over at CNC Kitchen shows us a literal twist on the concept, with this four-axis non-planar printer. For obvious reasons, it’s called the “RotBot” and it comes via the Zurich University of Applied Sciences, where [Michael Wüthrich] and colleagues have been experimenting with different slicing strategies to make overhang printing more manageable. The hardware side of things is actually pretty intuitive, especially if you’ve ever seen an industrial waterjet cutter in action. They modified a Prusa printer by adding a rotating extension to the print head, putting the nozzle at a 45° angle to the print bed. A slip ring connects the heater and fan and allows the head to rotate 360°, with the extruder living above the swiveling head.

On the software side, the Zurich team came up with some clever workarounds to make conical slicing work using off-the-shelf slicers. As [Stefan] explains, the team used a “pre-deformation” step to warp the model and trick the slicer into generating the conical G-code. The G-code is then back-transformed in exactly the opposite process as pre-deformation before being fed to the printer. The transformation steps are done with a bit of Python code, and the results are pretty neat. Watching the four axes all work together simultaneous is quite satisfying, as are the huge overhangs with no visible means of support.

The academic paper on this is probably worth a read, and thankfully the code for everything is all open-sourced. We’re interested to see if this catches on with the community.

Continue reading “RotBot Adds A Extra Dimension To 3D Printing, With A Twist”

Go Big Or Go Home: 0.6 Mm Nozzles Are The Future

Most desktop fused deposition modeling (FDM) 3D printers these days use a 0.4 mm nozzle. While many people have tried smaller nozzles to get finer detail and much larger nozzles to get faster printing speed, most people stick with the stock value as a good trade-off between the two. That’s the conventional wisdom, anyway. However, [Thomas Sanladerer] asserts that with modern slicers, the 0.4 mm nozzle isn’t the best choice and recommends you move up to 0.6 mm.

If you know [Thomas], you know he wouldn’t make a claim like that without doing his homework. He backs it up with testing, and you can see his thoughts on the subject and the test results in the video below. The entire thing hinges on the Ultimaker-developed Arachne perimeter generator that’s currently available in the alpha version of PrusaSlicer.

We’ve experimented with nozzles as small as 0.1 mm and, honestly, it still looks like an FDM 3D print and printing takes forever at that size. But these days, if we really care about the detail we are probably going to print with resin, anyway.

There are a few slicer settings to consider and you can see the whole setup in the video. The part where an SLA test part is printed with both nozzles is particularly telling. This is something that probably shouldn’t print well with an FDM at all. Both nozzles had problems but in different areas.

Continue reading “Go Big Or Go Home: 0.6 Mm Nozzles Are The Future”

SuperSlicer Reviewed: Another 3DP Slicer?

When you think of slicers for FDM 3D printing — especially free slicers — you probably think of Cura, Slic3r, or PrusaSlicer. There are fans of MatterControl and many people pay for Simplify3D. However, there are quite a few other slicers out there including the one [TeachingTech] has switched to: SuperSlicer. You can see his video review, below.

Of course, just as PrusaSlicer is a fork of Slic3r, SuperSlicer is a fork of the Prusa software. According to the project’s home page, the slicer does everything Prusa does but adds custom calibration tests, ironing, better thin wall support, and several other features related to infill and top surfaces. The software runs on Windows, Linux, or Mac.

Continue reading “SuperSlicer Reviewed: Another 3DP Slicer?”

Open Source CAM Software In The Browser

3D printers, desktop CNC mills/routers, and laser cutters have made a massive difference in the level of projects the average hacker can tackle. Of course, these machines would never have seen this level of adoption if you had to manually write G-code, so CAM software had a big part to play. Recently we found out about an open-source browser-based CAM pack created by [Stewert Allen] named Kiri:Moto, which can generate G-code for all your desktop CNC platforms.

To get it out of the way, Kiri:Moto does not run in the cloud. Everything happens client-side, in your browser. There are performance trade-offs with this approach, but it does have the inherent advantages of being cross-platform and not requiring any installation. You can click the link above and start generating tool paths within seconds, which is great for trying it out. In the machine setup section you can choose CNC mill, laser cutter, FDM printer, or SLA printer. The features for CNC should be perfect for 90% of your desktop CNC needs. The interface is intuitive, even if you don’t have any previous CAM experience. See the video after the break for a complete breakdown of the features, complete with timestamp for the different sections.

All the required features for laser cutting are present, and it supports a drag knife. If you want to build an assembly from layers of laser-cut parts, Kiri:Moto can automatically slice the 3D model and nest the 2D parts on the platform. The slicer for 3D printing is functional, but probably won’t be replacing our regular slicer soon. It places heavy emphasis on manually adding supports, and belt printers like the Ender CR30 are already supported.

Kiri:Moto is being actively improved, and it looks as though [Stewart] is very responsive to community inputs. The complete source code is available on GitHub, and you can run an instance on your local machine if you prefer to do so. Continue reading “Open Source CAM Software In The Browser”

Rarely Adjusted Slicer Setting Makes A Difference

When you 3D print something, you probably adjust the layer height based on your desired print quality. Speed is another parameter that many people adjust. But what about extrusion width? The parameter is there, but most people leave it at the defaults. [Stephan] wondered about it, and after running some tests, made a video you can see below trying to determine if it affected strength and print quality.

The tests were pretty straightforward. Some Benchys and other test pieces at each setting were observed and — in some cases — destroyed. He ranged the width from 90% to 250% of a 0.4mm nozzle. Important to note, his results are from a nozzle that has a flat lip around the aperture. If yours doesn’t look like that, you will see different results.

Continue reading “Rarely Adjusted Slicer Setting Makes A Difference”

There’s More To The 3D Print Than The Eye Can See

If you thought CADing designs for 3D printing was hard enough, wait until you hear about this .stl trick.

[Angus] of Maker’s Muse recently demoed a method for creating hidden geometries in .stl files that are only revealed during the slicing process before a 3D print. (Video, embedded below.) The process involves creating geometries with a thickness smaller than the size of the 3D printer’s nozzle that still appear to be solid in a .stl editor, but will not be rendered by a FDM slicer.

Most 3D printers have 0.4 mm thickness nozzle, so creating geometries with a wall thinner than this value will result in the effect that you’re looking for. Some possible uses for this trick are to create easter eggs or even to mess with other 3D printing enthusiasts. Of course, [Angus] recommends not to use this “deception for criminal or malicious intent” and I’d have to agree.

There’s a few other tricks that he reveals as well, including a way to create a body that’s actually a thin shell but appears to be solid: great for making unprintable letters that reveal hidden messages.

Nevertheless, it’s a cool trick and maybe one of those “features not bugs” in the slicer software.

Continue reading “There’s More To The 3D Print Than The Eye Can See”

3D Printering: The Past And Future Of Prusa’s Slicer

If you own a desktop 3D printer, you’re almost certainly familiar with Slic3r. Even if the name doesn’t ring a bell, there’s an excellent chance that a program you’ve used to convert STLs into the G-code your printer can understand was using Slic3r behind the scenes in some capacity. While there have been the occasional challengers, Slic3r has remained one of the most widely used open source slicers for the better part of a decade. While some might argue that proprietary slicers have pulled ahead in some respects, it’s hard to beat free.

So when Josef Prusa announced his team’s fork of Slic3r back in 2016, it wasn’t exactly a shock. The company wanted to offer a slicer optimized for their line of 3D printers, and being big proponents of open source, it made sense they would lean heavily on what was already available in the community. The result was the aptly named “Slic3r Prusa Edition”, or as it came to be known, Slic3r PE.

Ostensibly the fork enabled Prusa to fine tune print parameters for their particular machines and implement support for products such as their Multi-Material Upgrade, but it didn’t take long for Prusa’s developers to start fixing and improving core Slic3r functionality. As both projects were released under the GNU Affero General Public License v3.0, any and all of these improvements could be backported to the original Slic3r; but doing so would take considerable time and effort, something that’s always in short supply with community developed projects.

Since Slic3r PE still produced standard G-code that any 3D printer could use, soon people started using it with their non-Prusa printers simply because it had more features. But this served only to further blur the line between the two projects, especially for new users. When issues arose, it could be hard to determine who should take responsibility for it. All the while, the gap between the two projects continued to widen.

With a new release on the horizon that promised to bring massive changes to Slic3r PE, Josef Prusa decided things had reached a tipping point. In a recent blog post, he announced that as of version 2.0, their slicer would henceforth be known as PrusaSlicer. Let’s take a look at this new slicer, and find out what it took to finally separate these two projects.

Continue reading “3D Printering: The Past And Future Of Prusa’s Slicer”