First, apply a uniform coat of ageing varnish. Then wait either 1.5-2.5 hours (for large cracks) or 2.5-4 hours (for fine cracks). The varnish must be moist to the touch but not tacky. Then apply a thin coat of Cracking Varnish in the opposite direction to that in which the coat of Ageing varnish was applied.

Why did my varnish crack?

Some of the most common mistakes that lead to cracking include applying the finish too thick (common with conversion varnish), using a hard/brittle finish over a softer/flexible finish, or using the wrong finish for the job.

What makes clear coat crack?

Environmental conditions: Excessive heat or humidity during application and curing can cause surface imperfections such as cracking. Too much, too quickly: Spraying too much material in full wet coats can lead to cracking.