If you've been reading The Ruins lately, you might think I'd put my 3D printing hobby on hold, since I've been focusing exclusively on amateur radio. But, not only have I still been printing, I've made some significant investments in my set-up. Seizing on the opportunity to work from home full time, I finally gave-up the lease on my city apartment of the past nine years -as much as I loved it- and moved to a more spacious home (station, outpost, lair etc). Here, I have a basement workshop to set-up my lab. And, I used the space to replace my old Sermoon V1 with two awesome, but very different, printers: The Creality K1 Max, the high-end workhorse, and The Creality Ender 3, a different thing entirely.
I cannot stress enough how different these two printers, the K1 Max on the higher-end of the newest crop of 3D printers, and the Ender 3 being one of the cheapest printers available, and rapidly becoming outdated. However, working with both of these machines, as well as engaging with the greater 3D printing community online, I've learned a lot and boosted my skill and expertise to the next level.
If you recall from my previous articles on 3D printing, I basically stuck to making toys and cool models, and doing very little with the slicing software other than scaling, splitting and adding details to existing models and .stl files. Yes, I could adjust the supports and adhesion when necessary, but I mostly stuck with the recommended factory settings. After I moved, and my Sermoon V1 broke down, I started browsing the Reddit 3D printing communities, and noticed just what a wide range of print-qualities, and styles, were actually out there. I had assumed things like layer-lines, seams, and bumpy or grainy prints were standard, but even the basic store-brand slicing software has a lot of options to mitigate, or even totally hide some of the tell-tale signs of 3D printing, making a model look like it was cut strait from marble.
Leveling has always been important, as I first found out, but temperature, print speed, material selection, and even the texture and cleanliness of your build plate can have a drastic impact on the quality of your print. Having two printers, one of which prints up to 10 times faster than my old one, makes it much easier to test new settings. Seeing and tweaking the print settings on my models makes a difference between one test print and the next. Without going into everything, I'll detail the major aspects of what I learned below...
Printer Quality Simply put, the higher the quality of your printer, the better your models will look with less effort. That doesn't mean a less expensive printer won't create beautiful, professional quality models, just that the cheaper models require more work and time from the user to achieve the same result.
The Creality K1 Max, which retails for about $800 USD, is one of Creality's best printers, and it's light years ahead of my other printers. Of course, the trade-off is that it costs twice as much as the other two combined. It supports just about every material type for stereolithography (SLA) printing, and as long as the temperature settings are correct, it will produce quality-looking prints for each. This, compared to the Ender 3, which only supports PLA filament out-of-the-box, and my previous Sermoon V1, which supports PLA and ABS (but seemed to clog and fail repeatedly when using the more robust ABS plastic). Most notably the K1 Max prints way faster, with no loss in quality. It also offers LAN (over-network/WiFi) printing, and a built-in camera so you can monitor larger projects remotely, and easily pause or cancel them if something goes awry.
Perhaps it's best feature is true auto-leveling. Unlike my other printers, which I level manually, continually making sure each corner of the printing surface is perfectly level -to a paper-thin threshold -with screw knobs, the K1 Max uses a laser beam fixed to the extruder to perfectly re-level itself before each print.
Adhesion & Support This was obvious even as a novice printer. Without bed adhesion, glue, a textured build-plate or a brim around the bottom edges of your print, you could see corners of your print warping, or even the whole model slide off the surface. And, supports are often necessary with large over-hangs which will collapse if there's not a temporary support structure holding it in place.
Basic slicing software, such as Creality Print and Cura UltiMaker, will alert you if there's a danger of an over-hang collapsing or an adhesion issue, then add the recommended accommodations, but often these standard recommended support and adhesion tools ruin the quality of the print itself. For example, an adhesive brim may not totally tear away after printing, leaving unsightly plastic burring from the bottom edges of your model, and some supports leave marks after being removed, or worse, are so stuck on the model, they break it when detached. Sometimes these safety features are so over-done, it's worth risking a failed or collapsed print just to go without them.
However, with more experience on the slicing software, there are details I've become more accustomed to "fine-tuning." For example, you can adjust the spacing and perforation connecting the superfluous support and adhesion structures so they still hold the print safely, but remove easier with minimal scaring to the details of the actual model. After more time printing, I often dispense with the standard settings, and set my own preferences as I know more precisely how well my printers hold certain over-hangs, and how well certain sizes and shapes stick to the build plate. Often, zero or minimal superfluous structures are needed, but it took some time before I became confident abandoning the standard settings which are there for good reason.
Cooling A good cooling fan, and well programed "slice" or .gcode file, which tells the printer how exactly to print your shape or model, are important parts of the process. Just about every SLA printer will have a model fan which cools the model and the extruder nozzle throughout the print. Using the advanced settings, you can choose when, during your print, to employ the fan for the best result. Basic settings will engage the fan once the nozzle gets to a certain temperature. But, when slicing, you can also choose to employ the fan at critical points such as when the print handles overhangs. This way unsupported filament gets "frozen" in place, rather than melting downward when there's nothing beneath it. You can also employ the fan after the first few layers of a print, so it holds in-place steadily before continuing onto subsequent layers.
Ironing & Z-seam positioning One inescapable reality of 3D printing, is the noticeable texture of prints compared to conventional manufacturing. SLA printing is done in layers, leaving a visible, lined texture throughout most prints, and a seam where the printer stops one stream of filament and adds another. In many cases these tell-tale signs of a 3D print are subtle, and sometimes add character to the print, but when it's important for the product to have a smooth seamless surface, your slicer application has ironing and seam-hiding options to program into your model's gcode.
Ironing, as the name suggests, is just like a clothing iron. It's essentially a finishing option where the heated nozzle will go over the top or all visible layers of the model one or more times without extruding filament in order to smooth the final product. The quality on the ironing job will depend on the quality of the printer as well as the material and color you're using. For example, a graded, silky color may not look as good flattened as it does printed naturally, and certain types of material, like darker ABS colors are prone to show signs of swirling, melt lines, where the ironing takes place. So like other advanced settings, it's best to try different tests with each print to get the best result.
Additionally, most slicers will allow you to position the Z-seam -the visible line along which the nozzle stops and reverses direction- on the back of a model or even at a natural angled corner so it's not as visible. You can also stagger the reverse positions on each layer, so there is no single seam. However, sometimes this stagger can result in bumps or blemishes as the seam starts and ends at various points along the print, rather than hidden along one edge.
There is no perfect finish-type for all prints and models, and many
people will still sand, paint and polish their models post-print to get
it just right.
Stay tuned for future editions of the Fabrication Lab where I'll cover more topics, including a review of the Creality K1 Max and Ender 3; an article on using third-party upgraded parts for the Ender 3, including an all new MicroSwiss replacement extruder, and a deep dive into CAD modeling on Rhinoceros software and creating a new stl file from scratch. I'll also post some of my very own 3D designs made with Rhino 8.
