Manual model design silicon

Brief description of manual molding silicone rubber
Manual mold silicone is a flowable liquid, and the quality has nothing to do with the color. It consists of two components. Part A is a flowable liquid silicone rubber, part B is the curing agent. Firstly, after dealing with the original model, take some liquid silicone rubber , add 2%-3% curing agent of the amount of silicon, and mix them evenly. Then after vacuum-pumping the mixture, you can pour it into the mold frame. The silicone mold will cured in 2-3 hours.
Note: The time for vacuum-pumping should be less than 3-5 mins ,otherwise, once the silicone rubber has cross-link reaction during vacuumizing, it will not be operated.

Applications of manual molding silicone rubber
Manual molding silicone rubber is mainly used for model design of manual mold, PVC plastic molds, cement products, low melting point alloy molds, alloy toys, plastic toys, electronics, handicrafts, stationery, large-scale sculpture, reproduction of cultural relic, shoe sole molds, pad printing allocation, Electronic equipment antivibration, etc.

Brief features:
1. Good elasticity 2. Non deformation 3. Heat resistance 4. Low shrinkage.

Model code:
HY-528# is applicable to make molds of smaller products and the reduplication will be 2-3 times.
HY-540# , compared to other two types, for its moderate hardness and better quality & performance, its reduplication will be 20-30 times.
HY-570# is applicable to large size products duplications and Electronic equipment antivibration.

Operation Instruction for Manual Mold Silicone rubber:
1)Correct mixing ratio
Component A is silicone rubber, and component B is curing agent or vulcanizing agent, usually the mixing ratio will be 2-3%. Such as to 100G silicone rubber should be added 2G catalyst and then mix them totally(Note: the weight of the silicone and catalyst should be weighted correctly. According to local weather, the mixing ratio can be 100 to 2 under room-temperature 25 0C; if the local weather is about 10 0C, then the maximum mixing ratio should be 5%; When local temperature is -5 0C, no reaction will happen between the silicone and hardener; once the temperature of local weather is 38-45 0C, the mixing ratio of silicone and curing agent should be 1 %).
2)Preparation of the Original molds
Firstly, you should deal carefully with the Original mold or the products you want to be molded. If no polishing of the Original mold or the products you want to be molded, the surface of it is not so smooth or perfect, then the products made out of silicone molds will be not up to standard.
3) Vacuum-Pumping Process
mix the silicone and catalyst with a standard mixing ratio and then do the process of Vacuum-Pumping. Bubbles will come out during the mixing of the silicone and hardener, if without Vacuum-Pumping, the bubbles cannot be released from the mixture, as a result, there will be many bubbles in the finished silicone mold. Then the mold has a worse tensile strength which will affect the reproduction times. Such an unsmoothed silicone mold will affect the quality of the production directly.

Frequently asked questions of manual molding silicone rubber
1. How to deal with the bubbles during the mixing process?
It depends on your practical situation. Firstly you can deal the mixture with a vacuum machine if you have one; If no such machine, you can reduce the mixing ratio of the hardener from 4% to 1%-2%.Then in the prior period of the reaction of the mixture will be slower, then the air in the mixture will exhaust by itself for a longer curing time to release the bubble.
2. what should you do for imcomplete curing after the mold is finished?
Two causes lead to this problem: 1 Inexact mixing ratio, not to weigh following the standard ; 2 The mixture of the silicone and catalyst is not mixed evenly. You should avoid this kind of problem ,otherwise there will be a waste of silicone mold.
3. The solutions of the sticky of the silicone mold?
The main reason for this problem is that you do not handle the products or original molds well, then you should deal with the original mold or products carefully before molding. Such as for the products with a complicated
pattern or a unsmoothed surface, you should polish and clean the products after which it will be molded ,then spray the release agent. Normally, the release agent can be Vaseline , detergent. liquid wax Etc. In practical process, you can brush different release agent according to different material.
The second reason is that the operator pour the silicone into the mold when the mixture is mixed evenly, then the finish silicone mold will partialy cured.
4. What should you do for deformation of the silicone mold ?
It should deal apart according to the size of the products, In principle, the hardness of the silicone should be consistent to the size of the products. For the small size products with detailed patterns, the soft silicone can be applicable which the shore A should be 15-20 for easy demoulding and not damage of the patterns. Other wise harder silicone should be needed for large size products, such as products with size 50cm will need harder silicone with 40-50 shore A , then no-deformation. If Large products but features detailed patterns then 30 shore A silicone will be workable.(The process should be a layer silicone add a layer fiber glass or cloth..).The outer of mold can be plaster, glass fiber reinforced plastic(unsaturated resin and fiber glass) to protect the products from deformation.