FRP mannequin mold making process
A. Original mold material
The master mold is the most important prerequisite for manufacturing high-quality FRP molds. The choice of the base material of the original mold is mainly determined by the type and size of the mold, and the experience obtained when making different types of molds. Based on the principle of layering thermodynamics, to eliminate defects such as different densities, joints, and screw holes on the surface of the original mold, a layer of material with uniform heat transfer speed and a certain rigidity must be used as the surface treatment material. On this kind of substrate, an easy-to-polish material is used to modify the accuracy and smoothness of the contour size of the original mold surface, and an air-drying gel coat with a high-gloss surface is used to obtain a high-brightness original mold surface. The accuracy, smoothness, and brightness of the contour size of the original mold surface directly determine the quality of the FRP mold. To ensure the accuracy and smoothness of the contour dimensions of the original mold surface, materials with the following characteristics are required:
1 (Air-dry jet type, can quickly accumulate a certain thickness
2 (Low clearance hole, easy to polish and shape
3 (Good temperature resistance
To ensure the high brightness of the original mold surface, materials with the following characteristics are required:
1 (air-dry jet type
2 (low clearance hole, easy to grind
3 (Good temperature resistance
4 (Surface is smooth and delicate
B, the requirements of the mold release material
1 (Ensure demolding
2 (Does not affect the surface brightness of the original mold
3 (The release material is not transferred to the mold
C. Material of mold:
The most important measure of the level of mold production is the brightness, smoothness, gloss, and surface porosity of the surface of the mold gel coat. This is determined by the level of technology. The length of the mold surface quality retention time, which is commonly referred to as the mold life, is determined by the mold material properties.
Mold gel coat:
Mould gel coats currently include vinyl mould gel coats and meta-benzene unsaturated polyester mould gel coats.
The resin structure of the mold gel coat gives the final mold surface mechanical strength, brightness, weather resistance, chemical resistance, and flexibility. The operation process of the mold gel coat is a crucial step in mold manufacturing. The mold gel coat is the entire mold. All the post-layup layers and structural skeletons serve the mold surface gel coat layer.
Mold gel coats require higher usage and curing conditions than general product gel coats. High-quality mold surfaces require very precise mold gel coat operations and mixing processes.
Therefore, the performance of mold gel coat materials, environmental control equipment, and technological level are the key to determining mold making. Mold gel coat construction technology and equipment
Using spray equipment to coat the mold gel coat is an important part of the mold manufacturing process. Two types of spray equipment can be selected, one is the equipment typically used for product gel coat spraying, and the other is an air atomizing pressure spray can. Both types of equipment produce high-quality gelcoat surfaces. However, you must consider the following points when operating:
For typical gel coat spray equipment, the curing agent is injected into the raw material by means of internal or external mixing. These spray guns are easy to use and are usually more efficient than watering cans. However, it should be noted that if there is a deviation in the proportion and distribution of the curing agent, a problem with the transmission system or a poor distribution of the fan-shaped mixture may cause defects in the gel coat.
Many mold makers choose to use an air atomizing watering can to eliminate deviations in the production process. In the watering can gun, the curing agent is manually mixed to ensure accurate proportions. In addition, the distribution of the fan-shaped mixture produces a very fine atomization effect, but the spraying speed is slower than the pumping system, and its working time is limited by the gelation time of the raw material.
Before using, use a pneumatic stirrer to thoroughly stir each barrel of mold gel coat and ensure that all the materials in the barrel are completely mixed. You cannot use manual mixing methods, and do not reduce the completeness of mixing because you are afraid of air mixing into the mold gel coat. Make sure that the gel coat on the bottom and the side of the bucket can also be completely mixed. Then, before use, allow the gel coat to stay for a few minutes to restore its own viscosity and defoaming.
Verify that the temperature of the gel coat is in the range of 23-28 ° C. If it is not in the range, measures should be taken.
c. Test and select the performance of curing agent in different types of materials and in different processes.
d. Gel time
The next step in gel coat quality inspection is to verify the gel time, which will prove whether the mold gel coat is within the specified range. Verifying gel time is a simple process and requires no equipment.
1.The test sample should reach the standard test temperature of 25 ° C;
2.Add the specified amount of curing dose and mix well;
3. Record the time from when the curing agent is added to the gel.