3D Printing Material Guide – What to Know About PVA

Polyvinyl Alcohol or PVA is a soft and biodegradable polymer that is extremely sensitive to moisture. PVA’s vulnerability to moisture is so extreme that it has actually become its main selling point. When exposed to water, PVA dissolves; this makes it a fantastic support material. It can be printed to provide full support for extremely complicated geometry and then trivially removed with no effort and leaving no marks.

Hardware requirements

• Bed Temperature: 45-60 °C
• Heated Bed: Optional
• Build Surface: PEI, Painter’s tape
• Extruder Temperature: 185-200 °C
• Part Cooling Fan: Required

Best practices and tips

With PVA’s extreme sensitivity to water, it must be stored in a dry box. For this, you want an air-tight container with a desiccant to preferentially absorb any moisture. If possible, you should use a dry box that features a filament guide tube, so it never has to be taken out.

If your PVA filament has already been affected by moisture, you’re likely to hear a crackling and popping sound when printing as the water evaporates. The resulting prints will have bubbles and holes; this may not sound like much of an issue for dissolvable support material, but it can also affect the main print material’s surface quality.

You can dry a wet filament in a dehydrator or in a low-temperature oven. However, if you do so, be very careful to keep the temperature below the glass transition temperature of the filament.

As PVA is expensive, it can be tempting to use it sparingly as a support material. While you don’t have to print large solid blocks of PVA, you will get the best results when you provide your main print with proper support. The best way to do so is to configure your slicing software’s support density settings to find the best of both worlds.

Advantages

• Water-soluble support material
• Doesn’t require special solvents to dissolve
• No additional hardware required

Disadvantages

• Extremely moisture sensitive
• Expensive
• Requires careful storage

Conclusion

This information should give you a great starting point for PVA printing. Have you got any specific projects for which you’re planning to use PVA? If so, let us know down below.