|Using a pressure chamber dramatically improved my resin casting.|
Getting into resin casting can be a difficult thing, with so many details to consider
(what silcone and resin to use, how to create effective vents, etc.), that it is easy to get overwhelmed. I found one of the trickiest elements was determining how pressure and vacuum chambers can be used to improve the process. Both are used to reduce bubbles in the final product, but since they work in very different ways, each is suitable for a different aspect of the process. A vacuum chamber is used to physically remove bubbles from a material (and all the air from the chamber itself) by creating a vacuum, while a pressure chamber shrinks any bubbles present in the material via pressure. Because the mixing process of silicone introduces air bubbles into it, a vacuum is applied to the mixture before
using it (pouring it) to create a mold. This is possible due to the slow curing time of most silicone (~5 hrs). Resin, however, solidifies much more quickly (~15 min.), making a vacuum not a viable way for removing the bubbles in resin before injecting it into the mold. Instead, the mold is placed in a pressure chamber after
the resin is added, to shrink any bubble to a negligible size. Although using both strategies are not absolutely necessary for creating molds and using them for casting, from experience, it dramatically improves the final product. I currently use both, and they allowed me to nicely cast the true-scale Space Marine that I recently built
. In this post, I wanted to talk about both vacuum chambers and pressure chambers, and how they were important for dramatically improving my resin casting abilities.