When you’re looking to optimize the use of your desktop 3D printer, it’s wise that you begin your journey by running a variety of tests to affirm the relationship between the machine and the material being used. A number of companies are dedicated to providing test models to help observe the aesthetic or functional aspects of the filament used.
Some researchers and companies, such as 3D Matter, have developed a rigorous process to compare the mechanical properties of different types of filaments. To test geometrical accuracy and visual quality of the filament, 3D models like 3DBenchy allow users to observe the aesthetic quality of the print. Even 3D printing manufacturers like Ultimaker have come provide sample files like the “Ultimaker Robot” with their 3D printers.
To help consolidate and optimize the vast range of filament tests, 3D printing filament expert Ian Hiscocks wrote his own brief guide on the most critical testing methods, entitled “Building a Robot Army”.
In this study, Hiscocks provides a comprehensive and compact methodology to test and enhance the visual quality of different 3D printing materials. Here’s a quick look at his filament testing procedure.
To start, Hiscocks first uses the “Ultimaker Robot”, a 26 x 15 x 25mm model that takes just about 50 minutes to print. A simple starting point, this Robot model has various features that includes angled overhangs, bridging, some fine details such as the ears and antenna. For those without an Ultimaker 3D printer, you can download a number of versions of this testing model on youmagine.com. In Hiscocks case, with a number of different filaments at his disposal, he soon had an entire army of robots, the best of which he kept for a reference model.
“Repeating the same tests for the next filament, and the next,” Hascock writes. “Testing different colours and makes, finding the ideal settings for each, temperatures, speed, and flow. All using either the original at 100um layers, or at 200um for flexible filaments, or one with a large brim for ABS testing.”
To find the ideal print temperature, Hiscocks employs the “Quick Temperature Filament Test” by Arjan.
This is a test piece that reduces the temperature every 10mm by 5°C, while each file tests a temperature range of 20°C. “I have a range of files for this spanning the temperature ranges from 170°C to 270°C for various materials, and checking out the finished print you can select the ideal temperature to a few degrees to print with,” Hiscocks explains.
The next test he runs is on the flow rate, which at the moment is a “Volume Flow Test” designed for the Ultimaker 2 by Arther.
“This is a test piece that prints at a static temperature increasing feed rates starting at 3mm3/s up to 10mm3/s and from this you can get a feel for how it will print as the speed increases and if you may need to increase the temperature,” said Hiscocks. At the moment, Hiscocks is working to design a simple set of stepped test pieces that will allow him to test the print speeds and flow rates that will keep an even speed.
Ian Hiscocks also utilizes the 3DBenchy torture test model, as well as the “Treefrog” by Morena Protti, which isn’t designed to be a torture test piece, but still manages to push visual boundaries of your 3D printer.
“3DBenchy is another great all round torture test piece,” Hiscocks said. “Testing the overhangs, bridging and fine details with the added benefit of being able to take measurements and compare them against the standard model dimensions, which also can measure shrinkage.”
The ‘Treefrog’ is a neat 3D model with overhang slopes on the belly and legs, retractions between the legs and body, while the slope of the back shows off layering quality. The model also has some fine detail, and on a high quality print you will be able to see the definition of the nostrils. Using special filaments like Glow, Thermo- or UV- reactive are kept by Hiscocks so he can test their reactions.
Hiscocks has performed an abundance of these tests, the outcome of which has gone to a good humanitarian cause. The majority of his test pieces are given away to children and people with interest in 3D printing. He also keeps a Ultimaker Robot of each material and color for his archive, as each model is the ideal size to keep in storage. Hiscocks currently utilizes an enhanced Ultimaker 2, and has created a number of robots in different scales and with different nozzle sizes.