Plastic Molding Engineering Co-Op - Spring 2027
Posted Sep 18, 2026 · We last checked this listing on Oct 6, 2026
Likely interview questions for this role
Written from this job description, not a generic list. Each one notes what the interviewer is really checking.
About your past
Tell me about a time you tracked down the root cause of a problem, in a lab, a project or a job.
What they are checking: Whether they dig past the first answer, which is how defect analysis is done well.
How careful are you with documentation? Tell me about a time accuracy in records mattered.
What they are checking: Whether they can keep the precise records that validation work on medical parts demands.
Tell me about a team you worked on where you had to learn from people more experienced than you.
What they are checking: Whether they can absorb guidance and work alongside engineers and technicians without needing constant direction.
What interests you about molding high-precision medical components specifically?
What they are checking: Whether they are drawn to this work for real reasons, which predicts how engaged they will be.
What would you do
You notice a defect during a trial that the engineer didn't mention. What do you do?
What they are checking: Whether they speak up about what they see, since a co-op's fresh eyes are useful only if they share them.
About the work
What do you know about how injection molding works, from resin to finished part?
What they are checking: Whether they understand the basic process well enough to contribute to mold trials from the first week.
What is a short-shot study, and what does it tell you about a mold?
What they are checking: Whether they grasp how fill studies reveal flow and imbalance problems, which is listed daily work.
If a multi-cavity mold is filling unevenly, what could cause that?
What they are checking: Whether they can reason about imbalance from runners, gates, temperature and tooling rather than guessing.
What do IQ, OQ and PQ mean, and why would a medical component maker care about them?
What they are checking: Whether they understand process validation and why regulated products require documented proof the process works.
What is a process window, and how would you help find one during a mold trial?
What they are checking: Whether they understand that a robust process makes good parts across a range of settings, not one magic point.
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As published by Flex.