In a perfectly multi colored part, the overlay is impossible to remove, and will tear before separating from the substrate, or even take some of the underlying material with it.
In most cases, we recommend a mechanical interlock to augment or even replace a chemical bond. This can be achieved by placing an undercut in the substrate part, or a series of reverse-tapered or counterbored holes into which the overmolding material can flow, assuring a no-fail mechanism in all but the most demanding applications. Anyway, we’ll check your design drawings and give our suggestions!
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