When it comes to these materials there are a few ways you can use them to make parts:
We offer all of these molding processes in our silicone manufacturing facilities in Albany, N.Y. because each one of them has their own place, and advantages, when it comes to production.
Compression Molding is the cheapest way to make a silicone molded part by far. We often recommend this for prototyping because it’s cheap and you can use either one of HCR or LSR materials. Some silicone manufacturers will tell you this method is labor intensive, and it is — a manufacturer must hand-load silicone into a two-plate mold before applying heat and pressure. While it is not suited to high-volumes, compression molding can be ideal for small volumes where precision is not the focus i.e. prototypes. The parts rarely look pretty, so we do not recommend this method for precision molding.
Transfer molding using HCR materials, and so milling is required before molding. Milling is a manual process and requires several end-over-end passes. It is used to freshen material, eliminating crepe hardening/structuring.
While Transfer molding is faster than compression molding, its cycle times are slower than Injection molding. Using HCR during transfer molding, most molds will not produce flash free parts, so this process also requires demolding and deflashing. Peroxide cured parts also require post-baking
Injection molding is by far the most efficient process and is geared towards high volume silicone manufacturing. It has a low labor content — the process is selectively automated to ensure efficiency — and so it’s by far the most popular choice of our partners. While this method is the most cost effective it’s worth noting initial set up is the costliest, which is why this makes the most sense for larger volumes. The parts injection molding produce are pristine and precise, which is a strong draw for businesses making pet, infant, or healthcare related products.