Parting line on the plastic injection molding  design tips :


Parting line on plastic injection-molding are a popular topic for product designers. Accordingly, this tip covers the types of parting lines you may encounter on plastic and liquid silicone rubber molded parts, and how you can properly address them.

When you are developing a 3D CAD model to be molded, you may not spend much time thinking about where its parting line will be, but it's worth noting because the location can affect your part in several ways. On some parts, the location for the parting line is obviously right down the middle, while on more complex parts, it may not be as obvious.


For example, a simple plastic cup. The outer face is formed by one mold half (A-side), while the cup's inner surface and brim will be formed by the other mold half (B-side). The parting line occurs along the outside edge of the brim of the cup. For other designs, parting lines vary with geometry. A mold yellow flower, which was used as an art piece for children, depicts a parting line along its outer petals .



Being Aware of Parting Lines

With all injection-molded parts, there are several ways to address parting line challenges. An awareness of the significance of the parting line is a good start. As stated earlier, parting line location is obvious and not a problem on many parts. For more complex parts, you may be able to use tools within some CAD packages to locate and evaluate split lines, or you can just upload a 3D CAD model online and we'll propose a parting line and suggest appropriate draft based on that orientation. Our software may also point out that the part cannot be made in a straight-pull mold and that design changes, side-actions, and/or pickouts may be required.