Electroplate plastic mold design
Plastic parts whether smooth electroplating and electroplating quality, first depends on the selection of plastic substrate. Plastic parts used for electroplating should ensure that their surface has no defects, no obvious directional structure and internal stress. Preparation of plastic substrate, including electroplate parts modeling design, mold design and manufacturing, forming methods and specifications.
Plastic is a nonconductor. Before conventional electroplating, a series of chemical treatments must be carried out to generate a conductive film on the surface, which is generally only 0.1 ~ 0.3um. Obviously, its electrical conductivity is worse than that of metal parts, so it is necessary to electroplate plastic parts. Under the premise of not affecting the appearance and use, the design should meet the following requirements as far as possible:
1. Please control the large end of bone position at (main glue thickness *0.4) -0.1
2. The PL line should not be exposed
3. Ear protectors need to pay attention to the structure of the inverted button.
4. The parting surface should be wider, and the PL mouth should not collapse and deform, which may easily cause electroplating effusion and affect the appearance.
5. All the Pl of the plating surface shall be left with 0.2 difference by the customer, which shall be covered by the side of the pieces. Electroplate plastic mold design
Electroplate parts one of the common problems: shrinkage.The causes of shrinkage usually have the following several points:
1. Product A side under the super thick rib.
2. Sudden change of product wall thickness.
3. Round corner shrinkage.
4. Product structure reduction.
5. Product edge shrinkage.
1. For the product structure design with ribs or hooks under side A of the product, in order to reduce the shrinkage risk, the size of the connecting part should be less than 1/3 of the product's big wall thickness, i.e. : A< 1/3b.
2. Round corners are reduced as shown in the figure below, usually because the included Angle on side A of the product is acute, and the outer round corners are relatively small.
1. Increase the outer rounded corners as much as possible, and the edge line of rounded corners should be better than the side wall, as shown in the pink line and blue line in the figure below.
2. Adjust the product side wall thickness to minimize the gap between the product diagonal and the product side thickness.
Electroplate parts common problem 2: sharp Angle.Sharp Angle will lead to electroplating when the discharge concentration, so that the product edge is not smooth and flat.
The edge Angle (A) is recommended to be not less than 75 degrees.If the edge of the product has a sharp Angle, it is recommended that the customer trim at least a small surface with a height of no less than 0.25MM, and the included Angle of the product is no less than 75 degrees.The sharp corner of the product is 8MM or so along the outer edge of the product. Electroplate plastic mold design