Coming to a Desktop Near You
The world of 3D printing is quickly making headway on the mainstream market, and it can’t be denied that elements of the additive manufacturing world are propelling us into the future.
As these machines are becoming more popular, they are finding their way onto the desktops of fan-boys, makers, and engineers alike – providing a fairly inexpensive and quick method for prototyping and design adjustment.
The desktop 3D printer realm is a complex one, with major companies scrambling to develop their own 3D printers or buying out smaller companies for their designs. At PD&D, we were inexperienced with 3D printers firsthand, until this spring. Saelig was kind enough to provide PD&D with an Afinia H479 3D printer, which they distribute, for review.
Read: Shot in the Face
Aside from trying to load unfamiliar software onto a company computer (admin rights), the initial setup was incredibly quick and easy. The software, which is fairly intuitive, uses STL files for printing, like most desktop 3D printers. After some minor calibration work – setting the platform height, leveling, and heating up the extruder – I was printing my first model. A convenient addition to the software program is the ability to disconnect the printer once the process has started, negating any need to keep an essential laptop chained to the desk.
The Afinia printer is a classy-looking machine that is commercially designed with a sheet metal enclosure over the stepper motors and slides, and a 3D-printed housing for the extruder.
After a successful first print, the extruder wasn’t sent back to a home position, due to a coding issue. As a colleague and I soon learned, the Initialize switch on the front is not for use while there is a print on the platform – a 3D-printed skull now looks like it received a lobotomy.
The machine was immediately turned off, but the enclosure does not have any bumpers, so without power, the motors no longer held the platform, and it smashed into the base. The printer has a sturdy build, but the sound of metal smashing on a $1,000+ machine is troubling.
After some trials and tribulations with more platform leveling, the prints finally stopped lifting off the platform, a common problem with all desktop fused deposition modeling (FDM) printers, according to the online forums. The leveling process required some trial and error, but with a small platform, squaring everything up was quite simple.
The Afinia was shipped with two types of ABS material, the company’s premium ABS filament, and a standard ABS filament. The premium filament, which retails on Saelig’s website for $44.99, was precise and clean. The standard filament, which retails for $31.99, was a little sloppy, left strings on the print, and adhered to the platform less often. Needless to say, it’s worth spending the extra $13 for the premium.
The Afinia H479 is truly an out-of-the-box 3D printer that is easy to use for amateur or first-time users, but also provides the precision that would make engineers with industrial FDM printers jealous.
Bigger, Not Better
After tooling with the Afinia’s 5” x 5” platform, LulzBot sent their TAZ 3D printer for review, which boasts the largest print volume of any printer under $5,000 – 298 x 275 x 250 mm (11.7” x 10.8” x 9.8”).
Though the LulzBot TAZ wasn’t as simple to set up, it required little mechanical aptitude and no tools to get printing. Since the TAZ boasts a large print envelope, it was assumed that it would take up more space than the Afinia printer, and it certainly did. TAZ takes up a lot of desk space, but the print platform is monstrous – throughout all of the attempted prints and two spools of material, I never managed to push to the absolute limits of the TAZ’s print volume, but I still came away with some very big prints.
With such a large build platform, I thought that leveling may be more challenging than it was with the Afinia, and it was. Upon the initial test print (a small octopus), the platform seemed fine – the sea creature was even and centered. After subsequent prints, the platform began to tip forward and, the extruding nozzle gouged into the glass bed, effectively tearing up the Polyethylene Terephthalate (PET) base material with each print attempt. After diagnosing that it wasn’t a software issue, I returned the following day with a level.
The leveling process consists of bolts on any of the four corners - trying to find that perfect spot where the platform has a consistent, and level, Z-orientation. A peg on the left edge of the bracket, which moves along the Z-axis, also has to be adjusted so it hits a sensor when the extrusion nozzle is a paper’s width off of the platform – again, lots of trial and error.
Once the platform was leveled, all operated well with the TAZ, though the PLA material had a similar quality to that of the cheaper ABS from Saelig/Afinia – sticking with quality (and pricier) ABS seems to be completely justified, unless print accuracy is negotiable.
The unique thing about TAZ, is the Libre Hardware concept. The company welcomes users to improve upon and tweak the hardware – i.e. It will never be locked. Locking hardware was been a popular practice among corporations, and it manages to keep users from fiddling with the components or changing coding. In fact, LulzBot offers a bill of materials and replacement components on their website, and most of the plastic elements are 3D-printed themselves – making replacement fairly cheap and simple.
While the printer can manufacture incredibly large and precise models (down to 75 microns per layer, with the stock nozzle), the software makes it a challenge to get much done without a struggle. Like the Libre Hardware concept, the TAZ utilizes open-source software for printer interaction and model slicing. Model slicing is required once you have an STL file, so the printer can interpret how to print each layer individually, effectively layering several 2D files into a completed 3D print.
The open-source movement has much to offer, but the 3D printing software (even the software recommended by LulzBot – Slic3r and Printrun) leaves a lot to be desired. For instance, there were several files that I had hoped to print, but the Slic3r program consistently crashed while exporting g-code (the file type used by 3D printers). That’s not to mention the clunkiness of the program when changing support layout or adjusting the size of a print. Afinia’s proprietary software is easier to navigate, operate, and use to just plain print.
The TAZ did not encounter the same issues that the Afinia had with prints lifting off of the platform. The Afinia uses a heated platform, with porous holes that help prints stick, but even when leveled there were still some print-peeling issues. The TAZ uses a more standard glass heated platform that is covered with a PET material to help prints adhere to it. As an extra precaution, and as a recommendation from the many LulzBot forums, I used an ABS/Acetone slurry to keep prints from lifting. In only a few instances, the print warped or lifted off the platform once the print was started.
LulzBot, using open-ended software and hardware, fittingly produces their own filament, which includes an array of experimental materials for FDM printers. Beyond the standard ABS and PLA filaments in varying colors, LulzBot also offers a variety of unique filaments as part of the company’s lineup.
Whether you’re using a Libre Hardware printer, which will improve as time goes on, or a commercially designed, professionally distributed desktop 3D printer, it can be said with conviction that we are still in the infancy of desktop 3D printing. Both of these printers displayed great strengths, but heavy weaknesses as well. For the engineer looking to rapid prototype at their desk, these printers are good for basic concept designing and seeing a part or product first-hand. When it comes to printing parts that operate and pieces that fit together, the Afinia H479 is the way to go, but for large prints and experimental concepts, the LulzBot TAZ provides lots of freedom.