PVA

PVA (polyvinyl alcohol) is a water-soluble support material. It is printed with a second extruder alongside the main plastic (usually PLA); after printing, the model is dropped in water and the PVA supports simply dissolve, leaving no marks. This lets you print complex overhangs and internal cavities that ordinary supports cannot handle.

What it is good for

• Dissolvable supports for complex geometry
• Internal cavities and channels unreachable by hand
• Perfectly smooth overhang undersides
• Dual-material printing PLA + PVA

Where NOT to use it

• Single-extruder printers — PVA needs a second one
• Supports for ABS/PC — their print temperatures differ too much
• As a structural material — PVA is brittle and water-sensitive
• Without drying — wet PVA will not print at all

How to print

• Nozzle temperature: 185–210 °C (compatible with PLA)
• Bed temperature: 45–60 °C
• Cooling: 0–50%
• Speed: 20–40 mm/s — slow, PVA is fussy
• Retraction: gentle — PVA clogs with prolonged heat
• Do not park PVA in a hot nozzle — it caramelizes and clogs

Drying and storage

PVA is one of the most hygroscopic materials — it is designed to dissolve in water. Wet PVA bubbles, clogs, and will not print.

• Drying: 45–55 °C for 6–10 hours (carefully — high heat damages PVA)
• Storage: strictly airtight with plenty of silica gel
• Signs of moisture: bubbling, clogs, ragged feeding

Pros and cons

• Fully dissolves in water with no residue
• Enables the most complex geometry
• Temperature-compatible with PLA
• Perfectly smooth support-facing surfaces

• Needs a second extruder
• Extremely hygroscopic and fussy
• Expensive
• Clogs the nozzle when overheated