Apply Crackle Size Step 1 before Crackle Step 2 to increase the size of the cracks you get. Size needs to set up first and get tacky before applying Crackle (about 30 minutes). After Crackle is applied, it is best to let it dry naturally to get the crackled effect. This can take up 5 hours or more depending on humidity. These products are self-cracking and will not crack the paint applied beneath it. The finish is clear and durable. Glaze Couture can be applied after the Crackle dries.