SLS 3D printing is evolving fast and many issues that used to prevent companies from acquiring an SLS 3D printer are now history. Here are some of the most stubborn myths that linger on and prevent companies from revolutionizing their R&D work.
Myth 1. You don’t need an SLS 3D printer if you have an FFF printer
FFF (Fused Filament Fabrication), also known as Fused Deposition Modeling (with the trademarked acronym FDM), 3D printers are great and have become much cheaper over the past 20 years. You can use an FFF 3D printer to check if your plastic components will fit and to get a realistic 3D view of your creation. FFF prints are strong in two dimensions but weak in the third. Simply put – if you apply force to the FFF 3D printed part, it will easily break.
An SLS 3D printed part is equally strong in all three dimensions. This makes it a realistic manifestation of the injection moulded or milled final component. SLS 3D printed parts enable the realistic testing of the finished product. Simply assemble the 3D-printed part and use the end product as intended. If the SLS 3D printed part holds, your test was successful. If it breaks, you know you have a design problem.
Myth 2. All SLS 3D printers are large industrial factory machines
There are indeed very large SLS 3D printers used to produce small and mid-volume production series. But if your primary purpose with the 3D printer is to support the R&D process, there are nimble SLS 3D printers that will print parts and components of industrial standards. Depending on what print volume your biggest parts will need, you should be able to find a machine that can be brought into your office through a regular door with ease. Also, it should be possible to plug it into a domestic power outlet and run it via integrated software that makes it easy to operate.
Myth 3. You need a specialist to operate an SLS 3D printer
This myth is partly true if you need an SLS 3D printer that churns out small to medium production volumes of a part. But if all you need are SLS 3D printers to print parts for your R&D or technical development teams, there are SLS 3D printers that come with printer-specific software, adapted to the SLS 3D printer. This drastically reduces the number of settings, making them plug-and-play machines that anyone in the team can use after only an hour of introduction. This is important because anyone regularly using an SLS 3D printer will experience a rapid feedback loop when designing and printing plastic parts, making the whole team much better at plastic construction.
Myth 4. SLS 3D printers are messy
Anyone who has filled or emptied a traditional SLS 3D printer knows that these machines use polymer powder as the raw material for printed parts. This powder is ca 0.1 mm in diameter, and can easily spill all over the place. A traditional SLS 3D printing workstation is typically recognized from a distance on the powder around it. And the operators had better protective clothing if they wanted to use their clothes in a social setting later the same day.
However, modern SLS 3D printers have solved the powder handling challenges. The filling can be handled using special containers that are attached to the printer, and the powder is transported into the machine without any spillage. Also, the de-powdering of the parts after the print is finished can be handled using sealed cleaning units, which use high-pressure water that binds the powder and prevents it from entering the air.
Myth 5. SLS 3D printing is more time-consuming than FFF 3D printing
SLS 3D printing is a lot less time-consuming than FFF printing if you calculate the labour time it takes from start to finished and cleaned up part.
All 3D print jobs begin with importing 3D models and placing them in the build volume from your computer. With SLS 3D printing, you can do this job once for a (large) number of parts, depending on the size of the object is vs the available print volume. Compared to FFF printing, this is in the vast majority of cases a great time saver for SLS 3D printing. When using FFF technology you can only place a certain amount of 3D models covering the build plate but it is very hard or even impossible to “stack” or place on top of other 3D models. In SLS the powder holds the 3D models in space and therefore you can place models freely and even place an object inside another.
Filling an SLS 3D printer with powder can be quick and clean (with an integrated system), or it can be a messy task, requiring cleaning afterward. So in absolute time, loading an SLS 3D printer takes longer than loading an FFF printer. But again, with SLS 3D printing, you do prepare a job for a (potentially large) number of parts, potentially making this time a lot shorter per printed part.
Then the machine is working for you, so it doesn’t really matter how long this step takes. The truth is that an SLS 3D print job needs to cool down after it is finished, so it will take longer before you can pick up your printed part. But waiting isn’t working time.
Remove powder or support structure
Now comes an exciting step: once an FFF part has been printed, all support structure needs to be removed, and the remnants and marks that they left behind need to somehow be removed as well. This can be very time-consuming. In comparison, the SLS 3D printed part needs to have the powder removed. This can be a very quick process with the right tools. Using a machine with a sealed-off compartment that offers high-pressure water in combination with high-pressure air makes powder removal the most effective, definitely winning the day for SLS 3D printing.
In summary, SLS 3D printing is in most cases a much quicker process compared to FFF 3D printing calculated as actual work time per printed part.