u/Firstmold

We normally start with the shot size and V/P transfer position, then try adjusting the injection speed, pressure limit, melt temperature, or mold temperature. We’ll also check the material, barrel, and nozzle for feeding or plasticizing issues.

If none of that works, we may have to modify the venting, gate, or runner. But mold changes can be a hassle. Anything else worth trying first?

Two-color injection molding is not just about appearance.
One of the first things to check is whether the two plastics can actually bond well.

If the material pairing is wrong, the part may look acceptable at first, but later fail during use, assembly, bending, or temperature changes.

I’m sharing a simplified compatibility reference here as an early screening tool. It is not a final material approval guide, but it can help narrow down options before tooling.

For people working with 2K / two-shot molded parts, which material combination has given you the most trouble?