[midlife]

Rick,
Some rubbers like silicone can be almost liquid in their uncured form, and can be injected into the mold. Rubbers like the EPDM used for the knobs are "rubbery". They are almost as hard as the cured rubber, except if you stretch it it won't spring back. These rubbers are usually compression molded or transfer molded.
For compression molding weighed out chunks of uncured rubber are placed in the mold cavity. The mold is then closed, and the rubber cures under heat and pressure.
With a transfer mold, the slug of rubber is placed in a pot in the top mold half, and a piston squeezes the rubber into the cavities.


Yes, the parts are still available elsewhere for $26.00. I don't know if they are the original OEM, or reproductions like mine.