Table of Contents
PVA - Polyvinyl Alcohol
Polyvinyl Alcohol is a water soluble, bio degradable and bio compatible material found commonly in pill casings and detergent capsules. As a filament PVA is typically used as a support material in multi material systems like a tool changing FDM 3D printer due to its unique property to fully dissolve in water. How ever this ability is also a disadvantage since PVA demands to be kept in a dry environment or the entire spool could be waterlogged in a matter of minutes.
Advantages
- Water soluble.
- Can be used for casting.
Disadvantages
- Water soluble.
- Not suitable for mechanical parts.
Variants
PVA filaments only come in natural coloration and does not contain fill additives such as glass fibers.
Baseline Printing Recommendations
These numbers are provided as a baseline, and need adjustment and calibration for your specific printer/filament/color combination.
Variant | Hotend Temperature | Heatbed Temperature | Chamber Temperature | Optimistic Usable Temperature | Drying Temperature |
---|---|---|---|---|---|
PVA | 220 | 60 | Not required | 70 | 80 |
Other notes
It is ideal to print PVA from a dry box with a bowden tube and a fresh silica gel packet to delay the ingress of moisture into the material.
If PVA filament soaks too much moisture, upon printing the material will turn white out of the hotend and loud crackling can be heard as the moisture evaporates from the material.
Additionally if the filament has soaked too much moisture, for example the spool was left unattended to outside of a dry box for a week then hydrolysis will degrade the material substantially and individual strands of the spool can fuse together upon attempting to dry it.
PVA becomes flexible when it is wet.
Print at slow speeds for best results.
For optimal bed adhesion it is recommended to apply a thin layer of glue stick.