The selection of mold opening form and mold line is very important. Firstly, it is for the convenience of mold removal. Secondly, the mold line should be selected in a way that does not affect the overall effect of the product. Thirdly, it does not affect the quality of the product. For example, if the mold line position of the water feature series products is too high, more materials are needed to seal the mold line, which makes it easy for the product to crack; The fourth is to reduce the number of process operations, such as opening half of the mold.
To prevent silicone from flowing around, fix the mold with wooden blocks or wooden boards within a regular range. When opening the mold, use wooden boards and oil mud to separate the first part to be opened. It is required that there is no gap between the oil mud and the mold, and the surface of the oil mud is smooth and flat.
After the above work is prepared, apply Vaseline or spray release agent on the gypsum mold or mold. Smooth products require a clean cotton cloth dipped in Vaseline and evenly applied to the mold. Keep it for 30 minutes until the mold fully absorbs Vaseline, and then wipe the surface of the mold with a clean cotton cloth to ensure a bright surface; Products with texture only need to be evenly coated with Vaseline to adjust the silicone according to the formula. When mixing silicone, it should be stirred in an irregular direction to fully mix the curing agent and silicone, and to minimize the mixing of air into the adhesive. For smooth products, it is best to draw a vacuum once when applying the first layer of adhesive, and maintain it for 7-8 seconds when the vacuum degree is required to be -0.1Mpa.
After the silicone is prepared, the mold should be made in a timely manner. Pour the adhesive onto the highest part of the mold by dripping, allowing it to flow naturally. If it cannot flow properly, use an oil painting brush to brush it in place. If it is a mold, the silicone gel should not only fill the entire product but also be evenly brushed on the adhesive. Each product should be coated with at least three layers of silicone, each with a thickness of 1mm. During the silicone coating process, it is required that each layer is cured before applying another layer. When applying the third layer, a layer of gauze should be added on top of the second layer to increase the strength of the silicone. The thickness of the silicone part of the entire mold should be controlled within 3-4mm according to the requirements of different product sizes, and the width should not exceed 60mm of the product width. The starting time for silicone gel to solidify is 20 minutes.
1. Wash and dry the mother mold, and apply a smooth treatment (you can apply a layer of demoulding wax or apply a layer of demoulding agent)
2. Put 500-1000 grams of mold silicone rubber (mold silicone, mold rubber, silicone rubber, silicone) in a plastic bowl for later use;
3. Weigh the hardener in a weight ratio (usually 1.5-2.5%) and add it to a container for mixing, stirring thoroughly and evenly;
4. Depending on the situation (especially the first layer), add a certain amount of silicone diluent. Until evenly mixed, usually 3-5 minutes.
5. After mixing mold silicone rubber (mold silicone, mold rubber, silicone rubber, silicone) with a hardener, the reaction occurs at room temperature and releases low molecular weight alcohols. To remove the alcohol molecules from the colloid, it is necessary to bubble under negative pressure for 1-3 minutes. It is also possible not to rely on equipment (mainly depending on the mold operator's operating experience)
6. Multi layer coating film molds should be cured simultaneously inside, inside, and outside. When the amount of curing agent is relatively small, the reaction time is prolonged, the reaction is sufficient, and the colloid is good. Therefore, it is best to use less curing agent inside and more curing agent outside. When painting, wait for the first layer (inner layer) to dry before painting the second layer. The operation time is 30-50 minutes, and the demolding time is 10-15 hours. The maintenance time is 24 hours. Pay attention to painting the first and second parts.
About mold silicone rubber,Please check :
Food grade silicone rubber for mold making IOTA 1500 
