Here is the result of the molding and casting of my tiny skulls.
Here is some photos of the whole process:
1- The molding material is Smooth-On Rebound 25, a popular 2 parts rubber like molding product. Simply mix equal parts of liquid from bottle A and B, stir and brush on the item in several coats to make a mold. If the items are small enough (like my skulls), it can safely be poured on the sculpts in 1 step (no layering).
2- I pinned the skulls to a piece of styrofoam and used some Magic Sculpt at the base of each skull to have a leak-proof “seal”. I used toothpicks and more Magic Sculpt to make “channels” through witch the resin will flow: it makes the casting part of the process a bit easier.
3- A frame was made out of Lego blocks. Then the pink molding stuff was poured on the skulls.
5- For the actual casting, I used Smooth Cast 320 resin, also made by Smooth On. It is a 2 parts resin that cures super fast (15 minutes) and doesn’t smell.
6- Mixed in equal parts from A and B bottles (I use cheap plastic syringes sold in drug stores for measuring medication). The mix has the consistency of liquid honey. I poured it in the mold and used a toothpick to gently stir it and “brush” it in the cavities to avoid the formation of air bubbles.
7- The resin turns white and starts to cool down (it gets quite hot while curing). I don’t actually wait 15 minutes to unmold: it is more like 10-12 minutes. The resin is still soft and I find it easier to unmold and to trim the flashing when the resin is not 100% cured. Once totally cured, this stuff has the consistency of hard plastic and can be sanded or cut, but it is more difficult.
Ok… Just a few thousands more and I will be able to recreate this as a diorama 🙂Return of the King – skull avalanche (youtube)