Know Your Filament - Nylon
What is Nylon?
Nylon is a synthetic plastic called Polyamide. Nylon is strong, durable and a tad bit flexible in thin wall. Nylon is hygroscopic, this means that it absorbs moisture. This can be helpful as printed parts are easily post-processed with fabric dyes and spray paints to alter the final aesthetics of the product. But it also makes nylon prone to absorbing moisture from the air, thus affecting its performance.Since nylon has such a unique durability to flexibility ratio, it is often used for functional parts. Think of prosthetics, medical equipment, connectors and living hinges.
Nylon 3D printing can be achieved with Fused Deposition Modelling (FDM), selective laser sintering (SLS), and MultiJet Fusion (MJF).
Pros & Cons
Nylon Printing Techniques:
Basic setting of printers:
- Nozzle Temperature:220°C to 270°C
- Bed Temperature:75°C to 90°C
- Print Speed: Around 40 mm/s (may vary)
Use all-metal hot ends:
Most 3D printers come standard with hot ends that use PTFE. PTFE begin to breakdown above 240°C and will burn. For successfully printing with nylon filament, you need a hot end that reaches temperatures of at least 250°C. Most 3D printers can easily be upgraded with an all-metal hot end in order to print at temperatures above 240°C (extrusion temperature). Before replacing your current printer's hot end, make sure to print the correct mount to attach the hot end to your 3D printer.
Like with any other filament, the bed surface to print nylon is very important. For nylon, glass plates are the build surfaces I have seen produce the most consistent successful results. With the addition of a PVA glue stick, glass surfaces provide the bed adhesion necessary to bind prints to the build surface for a smooth 3D printing experience.
One of the challenging aspects of using Nylon is the need for a special storage system. Unlike other filaments, you cannot keep the filament spool exposed to the air for extended periods of time. Nylon easily absorbs moisture from the environment. Printing the moist filament will result in print quality issues like a foggy rough surfaces or even tiny holes or bubbles on the exterior. These printing issues can also significantly decrease the strength and performance of the printed parts. The typical solution for this issue is to remove the Nylon spools from the printer once you are done, and store the spools in an air-tight container along with some desiccants to remove the moisture from within. If you do not want to constantly mount and remove your filament spool, there are also commercially available storage containers that will keep the filament dry, while allowing it to feed out of a hole in the container.
Use enclosure to prevent warping
Some high-temperature Nylons are prone to warping due to the large temperature change between the extruded plastic and the ambient environment. Heated beds can reduce the warping to some extent, but using a printer that has a heated chamber or enclosure would be the ideal solution. Keeping the air around your part at a temperature of about 45 ºC will help eliminate warping by reducing this temperature variation.