what you need to do when the silicone molds appear...

1. It may be cuased by an inexact mixing ratio of catalyst in silicone rubber.  Not adding catalyst following standard, the silicone molds might appear to un-cured.    2.  Didn't mix the silicone with hardness evenly and completely.     3. When working temperature is lower than 0 ℃, catalyst and silicone won't cause reaction.      4. Addtion cured silicone mold touched tin element of condensation type silcone.     Solution:    Operating silicone under room temperature, mixing catalyst into silicone with right exact mixing ration and stir the mixture completely and evenly before using it.     Meanwhile, never let your addtion cured silicone touch condensation type silicone products.