Step 6: Thixotropic layer
The better way to do this it to add a thickening agent to your silicone and brush it on. I used glass beads to achieve the same effect. BE SURE TO USE THE CORRECT RESPIRATORY PROTECTIVE EQUIPMENT WHEN USING GLASS BEADS. The dust from this stuff is glass, don't breathe it in!
Mix the glass beads into the silicone while mixing parts A and B. If you are using silicone thickener then add some pigment to give you contrast as in the last pour. I did not use pigment and the glass beads changed the color enough to cause the same effect.
Apply the thickened silicone at all the thin/weak areas of your mold with a bristle brush. Once again, use the heat gun to get the thickened silicone to run a little and remove any topical air bubbles.