Liquid mold silicone is widely used in handicrafts, figurine models, lighting accessories, electronic potting, architectural decoration, and small-batch prototyping. However, during actual mold-making, customers sometimes encounter reproduction failures—such as bubbles on the mold surface, incomplete detail reproduction, tearing during demolding, obvious dimensional deviation, or insufficient mold service life. These problems are often not caused by a single factor but are related to master part preparation, material selection, mixing and degassing, pouring method, and curing conditions.

Bubbles appearing on the mold surface are one of the more common issues. Bubbles may originate from air entrained during mixing, or from gas adsorbed on the master surface or air remaining in pores. If stirring speed is too fast or edge scraping is insufficient, air is easily entrained in the material; if vacuum degassing time is insufficient, bubbles are difficult to fully remove; if the master surface is porous or structurally complex, air may also become trapped in detail areas. To address such issues, one can start by reducing stirring speed, extending degassing time, optimizing pouring position, and pre-treating porous masters.

Incomplete detail reproduction is typically related to material flowability, viscosity, working time, and master condition. Silicone with excessively high viscosity may struggle to flow into fine textures; if working time is too short, the material begins to thicken before complete filling; dust, oil contamination, or mold release agent residue on the master surface also affects reproduction results. For masters with fine textures, numerous undercuts, or complex structures, selecting grades with better flowability is recommended, and confirming the master surface is clean and dry before pouring.

Mold tearing during demolding is mostly related to hardness selection, parting design, and demolding operation. If mold hardness is too low while the reproduced part is relatively heavy or structurally complex, tearing may occur from pulling during demolding; if parting line design is unreasonable and undercut areas cannot be smoothly released, damage risk also increases. Excessive force during demolding or forced pulling from weak points similarly easily causes damage. It is recommended to evaluate master structure before mold-making, reasonably set parting surfaces, and adopt slow, uniform separation during demolding.

Dimensional deviation is typically related to shrinkage rate, mold support, and curing conditions. Liquid mold silicone may undergo certain volumetric changes during curing; if material shrinkage control is unstable, dimensional deviation will occur in reproduced parts. For products with high dimensional precision requirements, materials with lower shrinkage and better batch consistency should be selected, with dimensional verification conducted during initial mold-making. In addition, if the mold lacks sufficient outer support, deformation may occur during pouring, also affecting finished product dimensions.

Insufficient mold service life may be related to material tear resistance, temperature resistance, use count, and cleaning methods. Some molds develop surface hardening, cracking, deformation, or detail blurring after repeated use, possibly because the material is unsuitable for the current pouring system, or the mold has been subjected to prolonged high stress during demolding. For molds requiring multiple reproductions, attention should be paid to tear resistance, media resistance, and dimensional stability, and use under high temperature, strong solvents, or improper cleaning conditions should be avoided.

After a reproduction failure, it is not recommended to simply change materials; instead, the entire process should first be reviewed. Checks can be conducted item by item from six aspects: master condition, material selection, mixing ratio, degassing time, pouring method, curing conditions, and demolding operation. When necessary, retain failed samples and communicate specific phenomena with suppliers—such as bubble locations, tear locations, dimensional deviation direction, and areas of missing reproduction—for more accurate cause identification.

Liquid mold silicone mold-making is a systematic endeavor. Material performance is important, but process details are equally critical. By standardizing master preparation, reasonably selecting hardness and viscosity, controlling mixing and degassing, optimizing pouring methods, and improving demolding operations, reproduction failure rates can be effectively reduced, and reproduction precision and mold service life improved. For first-time use or products with complex structures, it is recommended to conduct small-sample testing first and proceed to batch reproduction only after confirming process stability.

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