Jo Sonja's Crackle Medium is a transparent medium used to create fine, crackle finish over completed acrylic paintings. This medium dries clear and will produce a 'cracked varnish' effect like that found on old porcelain. Once dry, this medium is intended to be sanded smooth and antiqued to highlight crazed areas.
- Prepare piece and paint in the usual manner. Allow to dry.
- Using a soft brush, apply an even layer of Jo Sonja's Crackle Medium over the surface where the crazing effect is desired. The brush should be used similar to a palette knife, laying on the medium instead of 'brushing' it out. After it is applied to the surface, overbrushing or reworking produces very fine, wispy crackles.
- Crackling will occur if room temperature is moderate to warm. Do not touch during the drying process. If surface is uneven when dry, lightly sand.
- Medium will be cured when completely dry. To emphasize the crazing, brush a darker colour thinned with either Jo Sonja's Flow Medium or Jo Sonja's Retarder into the cracks. Use a soft cloth moistened with Retarder to remove excess colour.
- Practice on a sample piece is recommended before attempting a project.
Thicker applications of Jo Sonja Crackle over fresher paint will create larger crackle patterns.