Silicone RTV ZA 12 LT for flexible moulds, wax and soap
ZA 12 LT Zhermack is a silicone rubber liquid RTV2, two-component, addition-cure, with low hardness of 12 ± 2 Shore A. After mixing base with catalyst in ratio 1:1material vulcanizes at room temperature and forms an elastic mould with very good reproduction of details.
Best TOOLS recommends ZA 12 LT especially for achieving Flexible moulds for pouring wax and soapas well as for models with fine details, delicate shapes and areas with retention.
The hardness of Shore A reduced allows the controlled deflection of the mould during the demoulding. This is important when the cast piece has thin or sensitive details and must be extracted without excessive mechanical requirements.
Recommended applications
Casting moulds for wax
ZA 12 LT is the recommendation of Best TOOLS for the manufacture of flexible molds used in wax casting.
The hardness of only 12 Shore A allows easier opening and deformation of the mould during the demoulding. This feature is useful when the wax parts contain reliefs, edges, thin elements or details that can be damaged if the mould is too rigid.
Soap moulds
ZA 12 LT is also suitable for making Flexible soap moulds, especially when the model contains decorative details, textures, inscriptions or geometry that require an elastic mould for demoulding.
The flexibility of silicone allows the removal of the mould from the piece by the controlled deformation of silicone rubber, reducing the need to force the piece.
mould with fine details and retention
High fluidity helps the material penetrate the small details of the model. The manufacturer shall declare a reproductive capacity of the details of 2 microns.
ZA 12 LT is indicated by Zhermack for duplicating models with low retention, which makes it suitable for geometry where a more elastic mould is required.
Modelism and realization of moulds
Zhermack recommends ZA 12 LT for mould-making and model-makingdue to the precise reproduction, dimensional stability and mechanical resistance.
It can be used for technical models, decorative replicas, prototypes and other applications where the geometry of the piece requires the use of a flexible mould.
Tampography and seriography on ceramics
According to Zhermack documentation, ZA 12 LT can be used in tampographydue to mechanical resistance and the property of ink transfer.
The product is also indicated for ceramic seriographywhere the manufacturer mentions the precision of reproduction, mechanical strength and laser incision.
Practical advantages
Reduced hardness - 12 ± 2 Shore A
It allows soft and flexible moulds to be made easily deformed during demoulding.
High fluidity
The material flows easily around the model and penetrates into fine details and narrow areas.
Reproduction of 2 microns
Allows high precision copying of textures, reliefs and very small details.
Breakdown of 510%
The vulcanized mould can withstand significant deformities during the extraction of the piece.
Resistance to laceration of 8 - 10 N / mm
Contributes to the resistance of the mould in the areas requested mechanically during the demoulding.
High dimensional stability
The dimensional variation declared after 24 hours is only -0,05%.
Anti-adherence effect
Volcanized Silicone shows, according to the manufacturer, a very good anti-stick effect.
Resistance to aging and high temperatures
Zhermack mentions a remarkable resistance to high temperatures and aging. The technical chart does not specify a maximum usage temperature.
Main technical characteristics
- Type: Silicone rubber addition-cure RTV2, two-component
- Mixing ratio: 1:1
- Vascosity of the mixture: 3300 - 3400 cP
- Mixing time at 23 ° C: about 1 minute
- Working time at 23 ° C: 15 - 18 minutes
- curing time at 23 ° C: approximately 120 minutes
- Model demoulding: approximately 3 hours after starting mixing
- hard after 24 hours: 12 ± 2 Shore A
- Traction resistance: 2,5 ± 0,3 N / mm ²
- Landing at break: 510%
- Resistance to laceration: 8 - 10 N / mm
- Reproduction of details: 2 microns
- Dimensional variation after 24 hours: -0,05%
Compatibility
According to the Zhermack technical file, ZA 12 LT is compatible with:
- gypsum;
- coatings;
- Polyurethane resins;
- Acrylic resins.
The manufacturer also mentions a high chemical resistance to the aggressive components of some types of resins.
Wax and soap are recommended applications by Best TOOLS for ZA 12 LTEspecially due to the hardness of Shore A reduced and the flexibility of the mould obtained.
Recommended complementary products
- Mixture container - for controlled dosing and homogenization of the two components.
- Precision scale - helps respect the mixing ratio 1: 1.
- Mixture spatulas - useful for mixing the base with the catalyst.
- Vacuum chamber and pump - recommended when you want to reduce the air in silicone.
- Sulphur-free modeling plastic - useful for preparing models and making separations to certain types of moulds.
- SEPARATOR AGENT ZHERMACK - auxiliary product for applications where the controlled separation between compatible surfaces is necessary.
Common questions about ZA 12 LT
Conclusion
ZA 12 LT Zhermack is an RTV2 silicone of addition with low hardness, high fluidity and very good capacity to reproduce details.
For Best TOOLS clients, his main recommended use is the achievement of Flexible moulds for pouring wax and soap, especially when the pieces have fine details, reliefs or geometry that require an elastic mould for demoulding.
Simple mixing ratio 1: 1, working time of 15-18 minutes at 23 ° C, hardness of 12 ± 2 Shore A and elongation at break of 510% make ZA 12 LT an application-oriented product in which mould flexibility is an important selection criterion.
For complete technical values of the product see the "Specifications" table and for examples of use see the "Video" table.
How to use ZA 12 LT
Before dosing, mix the two components separately. This operation is recommended by the manufacturer to avoid the effects of possible sedimentation.
Weigh equal amounts of base and catalyst, respecting precisely the ratio 1:1.
Mix the two components approximately 60 secondsUntil you get a uniform color. Clean during mixing the wall and bottom to avoid areas with unmixed material.
After mixing, pour the silicone slowly, preferably from one point. Manufacturer recommends casting from a height of approximately 30 cm.
When the equipment is available, vacuum processing is recommended for reducing the air in the material.
At 23 ° C, the declared working time in the technical characteristics is 15 - 18 minutes, and the curing takes place in approximately 120 minutes.
The model can be separated from the mould at approximately 3 hours since start of mixing.
Important limitations and recommendations
Respect ratio 1: 1. The change in the ratio between the base and the catalyst can influence the reaction time and the final characteristics of the silicone.
The surfaces that come into contact with the material must be clean, dry and fat-free.
For demoulding, the manufacturer recommends the introduction of an air jet between the model and the mould. Avoid mechanical force using spatulas or other instruments that can damage or deform the mould.
The technical chart provided does not indicate a maximum operating temperature. For this reason, no thermal limit should be assumed based on the general statement of resistance to high temperatures.
Storage
ZA 12 LT has a declared validity term 18 monthswhen stored correctly at temperatures between 5 ° C and 27 ° C.
After use, close the containers thoroughly. Do not reverse the caps between the base and catalyst container, as contamination of the components should be avoided.
Preparation and application
- Mix the base and catalyst separately until uniform before weighing. The model must be clean, dry and free of grease; substances containing sulphur may inhibit curing.
- Weigh equal amounts: 100 parts base and 100 parts catalyst. Do not alter the catalyst quantity to speed up or slow down curing.
- Mix thoroughly until uniform, including the sides and bottom of the container. Avoid leaving any unmixed areas.
- Pour in a thin stream into one corner of the mould and allow the material to cover the model gradually. The data sheet recommends vacuum degassing to reduce bubbles.
- Observe the product-specific times and the temperatures at which they are specified. Demould after curing without forcing the mould or using sharp objects.
- Close containers tightly after use and do not swap the base and catalyst lids.
Consult the safety data sheet and batch label before use.
![[ZA 12LT-2Kit] ZA 12 LT](/web/image/product.image/1414/image_128/%5BZA%2012LT-2Kit%5D%20ZA%2012%20LT?unique=bc6b764)
![[ZA 12LT-2Kit] ZA 12 LT](/web/image/product.image/1414/image_1024/%5BZA%2012LT-2Kit%5D%20ZA%2012%20LT?unique=bc6b764)
