Tolerances you have to know!

Dimensional Tolerances for Rubber Molded Components

Unlike rigid machined materials, thermoset moulded elastomers do not lend themselves well to the same level of tolerance. 
Being thermally moulded, elastomers are subject to many variables. Temperature, cure time, mould tolerance, mould registration, compound variation, and shrinkage are almost need to be considered by mould makers.

Tolerances, you need to know!

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Need to remind when design SOFT RUBBER components!

If peoples ignore elastomers of the characteristics is more various change than plastic parts when process. If design tolerances are harsh require a high precision as a plastic part, the outcome is always a lot of uncertainty there.