Whether you choose unsaturated or epoxy casting resin, it is normal to have unevenness after the resin is cured. This is because the volume of the resin shrinks. But sometimes it is very small, and the specific effect is directly related to the quality of your resin. Low shrinkage and low exotherm casting resins can achieve more ideal results. Since a flatter and higher gloss effect is generally required, it is recommended that you grind and polish it.
There may be several reasons for pits after the crystal resin is cured:
1. Uneven curing: If the crystal resin is not evenly distributed during the curing process, some areas may not be fully or fully cured. This may be caused by uneven resin coating, insufficient resin or incomplete mixing. Incompletely cured areas will form pits.
Solution: Make sure the resin is evenly coated, the ratio of mixed resin and curing agent is correct, and cure according to the specified curing time and temperature.
2. The presence of bubbles: When the crystal resin is cured, if there are air bubbles that are not eliminated, pits may be left after curing. Air bubbles can form in the resin or on surfaces that come in contact with the resin.
Solution: Use vacuum degassing equipment to thoroughly degas the resin before applying it. Make sure to apply the resin on a flat surface and gently heat the resin surface using a degassing device or a heat gun to help bubbles escape.
3. Improper surface preparation: If the substrate surface is not properly prepared before applying the crystal resin, it may result in insufficient adhesion between the resin and the substrate, and pits may form after curing.
Solution: Make sure the substrate surface is clean, smooth, and properly prepared, such as sanding, cleaning, and degreasing, before applying the resin.
4. Improper curing conditions: The curing process of crystal resin is affected by factors such as temperature, humidity, and curing time. If the curing conditions are not appropriate, it may result in incomplete or uneven curing, resulting in pits.
Solution: Follow the correct curing conditions, including temperature, humidity, and curing time, as recommended by the manufacturer. Make sure to cure under suitable environmental conditions.
If pits occur, repair methods can be attempted, such as using clear filler resin or re-applying the crystal resin. However, the best solution is to avoid pits during the production process and ensure uniform curing of the crystal resin through correct operation and curing conditions.