The Pros and Cons of Compression Molding
1. Cost-Effective
Compression molding is often the most economical manufacturing method for producing simple, mostly flat, large parts. While some curves and pockets in designs are manageable, extreme angles and deep draws can be challenging to achieve.The lower pressures involved make tooling costs more affordable, and molds generally have a long lifespan without warping or needing replacement. To offset the costs associated with compression molding’s longer cycle times, manufacturers can use multi-cavity molds to produce several parts in a single cycle.
2. Produces Strong Parts
Compression molding creates solid parts without flow or knit lines, resulting in high structural stability.This method is also well-suited for manufacturing parts from composite materials, allowing for the easy production of durable, corrosion-resistant components and products.
3. Design Flexibility
Compression molding is an excellent tool for engineers and product developers.For instance, low-cost compression molding is ideal for prototyping. Simple compression molds can be designed in CAD software, 3D printed, and then used with a tabletop vise to form various materials. Later in this article, you’ll see an example of how OXO uses this method for prototyping.
4. Limitations
Despite its many benefits, compression molding has its limitations. It is not well-suited for manufacturing complex parts, especially those with steep angles or intricate details.Additionally, its cycle times, which can take several minutes, are slow compared to high-volume molding methods; for instance, injection molding can have cycle times of just seconds. The labor costs associated with compression molding can also be relatively high due to the lengthy cycle times, which result in increased working hours. Furthermore, flash and burrs must be manually removed from compression-molded parts, adding to the time and creating waste. Nonetheless, compression molding remains an important manufacturing method used to produce a wide range of everyday products.
