Home / Tools / Scrap and Regrind Planning for Injection Molding

Injection molding guide

Scrap and Regrind Planning for Injection Molding

How to separate yield arithmetic from material qualification when using regrind.

The engineering question

Measure good output, reject output, runner recovery, and purge independently. Then apply only the grade- and specification-approved regrind percentage to a defined blend.

What to document

Supplier processing guidance shows that regrind must be clean, appropriately dried, and limited by grade and quality requirements.

Practical workflow

Connect Scrap Rate, Regrind Blend, and Masterbatch Dosage.

Validation boundary

Use manufacturer documentation, grade-specific supplier data, controlled process records, and trials for any equipment, quality, material, or commercial commitment. A static calculator is a transparent starting point, not a simulation or approval.

Reference

BASF Ultradur processing notes