� Process Advantages◦ Once process settings are finalized, process can operate automatically with minimal human labor, except for secondary finishing.

◦ Process is capable of extremely complex shapes, although this must be balanced against higher tooling costs and more complicated operation and maintenance.

� Process Advantages◦ Because of the high pressures involved, process is capable of reproducing an excellent – even mirror surface finish, depending on finish on tooling.

� Process Disadvantages◦ Compared to other plastics processes, tooling costs are high.

◦ Some part details, such as undercuts, are not easy to construct in the mold.

◦ Parts with high levels of residual stresses can continue to shrink or warp for several days after molding.

� Process Disadvantages◦ It can take a long time to build the molds because of the tighter tolerances and making sure that the mold can withstand the high pressures that are needed for the process.

◦ It is hard to predict accurate shrinkage. Depending on how the part is processed, the shrinkage can be changed. The process has a huge effect on the parts final dimensions.

� Competing Processes◦ Except for large parts, hollow parts can be assembled from several injection molded parts.

� The traditional hollow parts processes are Blow Molding, Rotational Molding, and Twin-Sheet Thermoforming.

◦ Injection molding can make equivalent parts at higher tolerances, assuming volumes justify higher tooling and extra assembly costs, and aesthetic standards will allow a welded area around the part.