Let me share with you some of my experiences using PVA in AMS.

1. PVA must be dried:

You can use Sunlu S4 filament dryer or eSUN ebox lite for baking. It is recommended to put a thermometer and hygrometer in the baking machine to detect the actual humidity. Baking with a humidity of 15%~20% will be fine.

!!warning!!

Moist PVA will cause the filament to get stuck by the AMS internal hub motor, stringing, support lack of material, and reduce adhesion.

2. PVA is the same as TPU. The printing speed cannot be too fast. There is no need to change the printing speed of slices setting. You can limit the printing speed by setting the maximum volume flow rate.

The calculation formula is

maximum volume flow rate = layer height × nozzle diameter × printing speed (0.2mm × 0.4mm × 80mm/s = 6.4mm^3/s)

3. The length of PTFE tube should be moderate

The PTFE tube from the AMS Hub to the extruder interface cannot be too long or too short, because the AMS Hub detects the filament feeding status through the Hall sensor in it. We usually use PLA, PETG, Because ABS and other wires have a certain degree of hardness, they can smoothly push the Hall sensor back to the correct position. However, PVA is a soft wire and will bend and deform in the PTFE tube, causing the Hall sensor to The magnet of the nozzle cannot be pushed back to the normal position. At this time, the AMS Hub will determine that the residual wire in the nozzle cannot be squeezed out, and the material will be advanced and unloaded again. If it is repeated 5 times without success, the printer will pause and display " Extrusion failed, please check whether the extruder is blocked."

4. PVA filament setting

The maximum temperature in the Filament setting and the temperature of the build plate must be the same as the main material.