Two timelines on a log scale: acrylic becomes dry to the touch within minutes to a few hours and keeps hardening for up to about a year; oil is wet for about two days and keeps hardening for decades.

Concept · Working With Each

Open Time

Open time is how long paint stays wet enough to move around on the canvas.

Acrylic is dry to the touch in minutes to a few hours; oil takes about two days. That window decides how a painter works.

  • Oil invites wet-in-wet: new color worked into paint that is still wet, for soft blends.
  • Once acrylic has set, the next color sits on top with a clean edge.
  • Acrylic can be blended wet too, but only quickly.

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