Insert Molding in a Small to Medium Volume World

One of the more challenging issues encountered for injection molding is interrupting the injection cycle.

Molten plastic likes consistency. Consistent temperature, consistent cycle time, consistent viscosity.

Cycle time gets impacted when you need to add time to place objects, (inserts, rings, electrical contacts, pins, etc.) into the mold. In some cases, the part will be encased in plastic (magnets and sensors). In most cases, the insert will have to contact the other side of the mold upon closure, “shutting off” the flow of plastic at one end and allowing access to the insert in the finished part. Which is a challenge in itself, as most “inserts” are not made to tight tolerances, while molds typically require tight tolerances.

So, if you want to incorporate fasteners or higher level capabilities into your plastic/composite components, insert molding is another level up in injection molding and certainly something you need to consider in your sourcing effort.

PlastiCert has been insert molding our entire 40+ year history. We have done both encapsulation and flush mounting for threaded inserts.

Frame with 42 inserts                             Velocity wheel with magnet inserts and metal axle pin                       High temp Eng Resin with threaded inserts 

housing bezel with inserts for display mounting

Mold design and build for insert molding DEMANDS experience, to plan for and manage the various insert inconsistencies. PlastiCert has that experience and having both the mold design/build AND injection molding under the same roof is a major advantage in getting to production on time.

The biggest issue is managing the variables that plastic hates so much, time and temperature. Cycle time ALWAYS needs to be consistent, whether your molder is insert molding or not. Insert molding just adds another variable to the cycle time that takes experience and engineering to accommodate.

You can automate insert molding, as always the end-of-arm tooling will be the key aspect. If you are ordering small to medium volume, that cost will be prohibitive. Using an injection molder like PlastiCert, deeply knowledgeable in the impact of inserts on cycle time AND experienced in low and medium volume programs, is necessary for successful product launch!

So, when evaluating a potential injection molder and insert molding is within your possible needs, make it part of your evaluation. Assess their history and experience with diverse kinds of inserts and longevity of the programs they insert mold.

Which means, give PlastiCert a call. We have been doing insert molding with MANY types of inserts for our history.