ZA 13 MOULD WT 45
ZA 24 CONCRETE
ZA RTV 3060
A number of special formulas have been developed for this application, guaranteeing excellent dimensional stability over time and a high degree of chemical compatibility with the majority of concretes.
Zhermack poly-addition silicones stand out for their compatibility with concretes, fluidity, tear strength, resistance to alkaline environments, very accurate reproduction of detail and easy separation from the countermould (self-separating).
For correct use and to obtain the final product characteristics, you should use poly-addition silicones at a ratio of 1 part A-base:1 part B-cat (in weight). The surface must be completely clean. The solidification times of the silicones indicated in the data sheets refer to a standard temperature of 23°C. Temperature variations may affect solidification speeds, given that the hardening process is slower at temperatures below 23° C.
Once the products have been poured, the components should be mixed vigorously until a homogeneous compound is obtained, then poured onto the original model from a recommended height of about 30 cm. Once the silicone rubber has hardened to form the mould, this can be used to reproduce the original object a number of times by pouring the concrete into the mould.
Store the products at a temperature of between 5°/25°C and to close the bottles tightly after use.
Maintaining a vacuum over the silicone is fundamentally important to avoid "porosity" in the mould which could cause problems of dimensional stability later.