The methods to address difficult mold release in vacuum casting include:

(1) Use mold release agents: Apply appropriate mold release agents on the molds before replication. Mold release agents create a thin film between the molds and silicone, reducing adhesion and making mold release easier.

(2) Optimize mold design: Consider using smooth surfaces and avoid sharp angles or grooves to reduce the contact area between the molds and silicone. Ensure the mold surface is smooth, without scratches or damage.

(3) Control silicone curing time and temperature: The curing time and temperature of silicone also affect mold release. Follow the guidance of the silicone material and control the curing time and temperature to avoid excessive curing and increased adhesion.

(4) Apply mechanical assistance: During the mold release process, apply gentle mechanical assistance, such as tapping the molds or using hand tools to gently loosen them, to help separate the molds from the silicone.