[Chiuso] NylonX  

NylonX

Over the last week, I've been making a serious effort to evaluate the filament NylonX sold by MatterHackers. I mostly print functional parts, in the past using PLA. My objective with NylonX is to make parts that have a more professional appearance and better heat resistance, while maintaining strength and rigidity.

In most ways, NylonX has met my objectives. The parts look great, although bridging suffers significantly. I haven't had problems with blobs, stringing, clogging or warping. While these parts are not as stiff as PLA, they are stiff enough for the majority of my applications, and NylonX parts are much tougher. 

In comparing appearance, my PLA parts were printed with Prusament Galaxy Black (my new favorite PLA). Like carbon fiber filaments, Galaxy Black PLA does a great job of hiding the layer lines and improving the appearance of the top/bottom faces. It does this with a flat black color and little white speckles. PLA parts in the comparison were printed on Prusa's textured PEI bed, while NylonX parts printed on smooth Garolite. As a result, the bottom faces of the PLA parts looked better than those in NylonX, largely because of the textured print bed. The other faces, both in NylonX and Galaxy Black all looked great. I would say it is subjective as to which looked best. The NylonX parts looked significantly better in all ways than PLA parts printed with traditional black PLA.

To test tolerance to heat, I placed two identical parts at the bottom of my PrintDry dehydrator (set at 170⁰F), one part printed in PLA, the other NylonX. After heating for an hour, the PLA part was easily deformable, while the NylonX part remained stiff.

To my surprise, the standard print times for the NylonX were not very much different than for the PLA. But while I would be comfortable using the printer's LCD screen to crank up the print speed to 150% for the PLA, I would not do so for the NylonX.

I printed the NylonX using an Original Prusa i3 MK3S (which includes an all-metal hot end). The only modification to the printer was that I changed the nozzle to a 0.4mm E3D V6 hardened steel nozzle. To ensure that the filament was dry, I used a PrintDry dehydrator, both to dry the filament before printing and as the filament dispenser while printing.

Slicing was done with PrusaSlicer version 2.1.0. My profile for printing NylonX was created by starting with Prusa's profile for Taulmen Bridge (a nylon based filament). Then made these changes in the Filament Settings tab:

• Extrusion multiplier: 1.05
• Density: 1.0
• Extruder temp first layer: 260
• Extruder temp other layers: 260
• Bed temp first layer: 60
• Bed temp other layers: 60
• Max volumetric speed: 4

In the Print Settings tab, I used Prusa's standard 0.20mm Quality MK3 setting. Note that no changes to printing speeds were made, as setting the Max Volumetric Speed had the desired effect of slowing things down a bit.

Before starting this project I learned that getting nylon to stick to the print bed is a problem. The wisdom from the web suggests that printing on a Garolite bed solves this problem, and I found that to be true. I love Prusa's auto-leveling print bed based on their magnetic steel sheets and PINDA probe. Unfortunately, most Garolite print surfaces are too thick to work with Prusa's system. 

Fortunately I found a guy that sells a Garolite print surface specifically for the MK3. Check it out here: 

https://www.etsy.com/listing/669225246/phenolic-le-generic-garolite-original

I purchased the $57 version of this build surface that comes assembled on a steel base. As recommended, I first thoroughly sanded the Garolite with 800 grit sandpaper. Calibrating the first layer height was done in the traditional manner, but I did notice that I only moved the print head down 0.3mm. This makes me think that some users may need to move the PINDA probe down 0.5mm to keep the print head from crashing into the bed. 

Before each NylonX print, I cleaned the Garolite surface with isopropyl alcohol. Parts stuck nicely to the bed while printing, finished parts were easily removed after letting the bed fully cool. (In setting the first layer height, be careful not to have the print head too close to the bed, or removing the parts from the Garolite can be difficult)

In conclusion I found NylonX easy to print and the parts looked great. The parts seem strong and tough, although less stiff than PLA. They are much more tolerant of heat. Bridging with NylonX is a concern, but this might be solved by fiddling with the fan settings. Because nylon is so hygroscopic, significate measures must be taken to keep it dry. While this is doable, it is also a nuisance. I'm not overly cost-sensitive, but it is worth noting that NylonX costs $0.12/cm3, while Galaxy Black is only $0.04/cm3.  A final concern is that it may be best to print nylon with ventilation as it has been reported that gives off styrene, a possible carcinogen.

One thing I do miss with NylonX is the textured bottom surface by using Prusa's Textured PEI build plate. I think next I will experiment with Priline's Polycarbonate Carbon Fiber filament which can be printed on the textured PEI bed.