The following tips will help ensure a higher rate of success when printing e-NABLE devices. In addition to the information below, you may want to watch the recording of Jeremy Simon’s presentation on 3D Printing Best Practices for e-NABLE Volunteers: [https://youtu.be/V6iVqB8ynYA](oembed:https://youtu.be/V6iVqB8ynYA) --- # Print Orientation and Positioning Many of these devices require some attention when printing. Because 3D printers fabricate objects from thin layers of plastic, there is a grain to the structure of the printed parts, much like there is grain in wood. Many of the parts used in the e-NABLE hands need to be printed in a particular orientation so that the “grain” of the print is oriented to maximize the strength of the part. For instance, most gauntlet designs need to be printed with the two arms in contact with the build platform. While this does require some amount of support material, it aligns the layers of the print with the directions of loading during use. **Incorrect orientation:**  *While this minimize support material, this orientation makes the now vertical arms quite weak.* **Correct orientation:**  *Proper gauntlet placement: both arms on the build platform for maximum strength.* It is also important to make sure that all parts are placed flat on the print bed surface to ensure proper bed adhesion. **Incorrect placement (not touching build plate):**  *If the object is not placed directly onto the build platform before slicing, it will likely not stick properly and will result in a poor surface finish or a failed build.* **Correct placement (touching build plate):**  *It is important to make sure that the bottom surface of each part of the print is firmly secured to the build platform, both for the success of the print and for the surface finish on the bottom face of the object.* # Materials Materials are still an area of active exploration. e-NABLE members are currently fabricating hands using PLA, ABS, Nylon, PETG, PLA+, Tough PLA, and others, each of which has specific printing requirements. Branebot put together a great Instructable describing [the process of printing a Cyborg Beast in Nylon and dying it](http://www.instructables.com/id/Techniques-for-3D-printing-in-Nylon/?ALLSTEPS). ### *Recommendations for PLA:* * Extruder: 180-230C (depends heavily on type of machine) * Bed: 0-60C ### *Recommendations for ABS:* * Extruder: 230-240C (depends heavily on type of machine) * Bed: 80-110C ### *Recommendations for Nylon:* * Extruder: 240C * Bed: 80C (PVA/Elmer’s glue stick helps with adhesion) * Retraction: 4mm or greater (based on MendelMax running Repetier firmware and * Nylon filament must be kept desiccated when not in use. # Calibration Dimensional accuracy is very important for these hands as there are a lot of moving parts that need to fit together precisely and with minimal play. The following resources can guide you through the calibration process for most desktop 3D printers: * [FDM Test Part with quantitative scoring methodology](https://www.thingiverse.com/thing:3193789) * [Solidoodle calibration guide on Instructables](http://www.instructables.com/id/How-to-calibrate-the-Extruder-on-your-3d-Printer/) * [RichRap’s RepRap calibration guide: Slic3r and extruder](http://richrap.blogspot.com/2012/01/slic3r-is-nicer-part-1-settings-and.html) * [RichRap’s Slic3r calibration guide: filament and printing](http://richrap.blogspot.com/2012/01/slic3r-is-nicer-part-2-filament-and.html) # e-NABLE Quality Specification In order to maintain quality prints across many different types of printers, we ask for volunteer fabricators to target the following quality specification: * No large gaps in between shells. The print must be “water-tight” * Layer height between 0.1mm and 0.25mm * No experimental, scented, or chemically-treated filament * Parts must be fabricated according to the above orientation guidelines * Printer must be properly calibrated to achieve the dimensional tolerances necessary for functioning hands