Do resin prints need to be cured after washing?

Yes. A washed print is only partly cured: its surface can stay tacky and its strength is lower until it is exposed to the right light for the time the resin maker advises. The part should be dry before curing, especially after a water wash.

Resin printing has two finishing steps after the print leaves the platform, and they only work in order.

Washing removes uncured resin

A freshly printed part is coated in liquid resin. Washing — in isopropyl alcohol for standard resins, in water for water-washable ones — removes that coating. The resin maker states which liquid to use and for how long.

Curing finishes the chemistry

Inside the part, the resin has been cured just enough to hold its shape. Post-curing with ultraviolet light completes the reaction: the surface loses its tackiness and the part reaches the strength its maker describes. The curing time and wavelength advice come from the resin label or data sheet.

Why drying comes between the two

A part that still holds alcohol or water can cure unevenly, and water-washable resins in particular can crack later if they are cured while wet inside. Letting the part dry fully before curing avoids that.

After curing

Supports come off more cleanly before curing on some resins and after it on others, and makers differ in their advice. Sanding, filling and priming follow once the part is cured. Cured resin dust from sanding still calls for a mask and for wet sanding where possible, and the washing liquid and any uncured waste are handled as the resin maker describes.