Rapid Tooling – some Injection Molding experiences


Rapid Tooling is a simplified injection molding mold. A better understanding of injection molding, will be good for cost saving and shortening lead time.  We organized some injection molding experiences, which confronted before. Just in occasions, they would be helpful for our customers when conducting product development.



  • FR resins (for example fire retardant ABS), if parts in this type of materials, it will be very difficult molded in snow white (similar as Mac Charger white), because of their natural colors. After adding fire retardant additive, FR resins would be a bit yellow in natural.
  • PC, polycarbonate, we would NOT suggest for using at frame covers, which with an open window in the center of the part. It’s because of its flowing property. Melting line will be easy to happen at frame part, if molded in PC (with bad flowing ability), melting line would be more serious. It would be better at using PC/ABS, or ABS.
  • POM, is NOT adhesive with other material in normal. It’s NOT suitable for common over-molding (hard-component with soft-component covered), while good for moveable over-molding. For example, the connection part between legs and body, hand and body of a Barbie doll. POM is also very good for bump-off, for trial of challenging undercuts.
  • If for enclosures (front cover & back covers), both with a same molding color, we would suggest to put them in a family mold, if without tooling structure concerns. Just in case slight color variance, at different molding situation, or at different batch of production.
  • Glass fiber additive can help parts stronger and more stable, and less shrinkage in thick sections. But please be careful at the parts with bad flowing ability, for example with PC. It will easily cause molding issues, for example short shot. Also, if for cosmetic parts, please be notified that there will be glass fiber mark at the top surfaces.
  • Injection molding resins will shrink in property. Different materials are with their own shrinkages. If for materials trial, or material testing with rapid tooling, kindly please note that different material may with different shrinkage, then cause dimensions variance. Try to find a series testing materials with close shrinkage, before tool building start.
  • Undercuts, normally would need sliders, lifters, or manual inserts for de-molding. If without cosmetic concern, we would suggest adjust them as shut-off structure, as many as possible. It can help saving tooling cost significantly.



Much more rapid tooling and injection molding experience and knowledge, we will try to organize and sort them out, clearly and understanding-easily at our website www.dankemold.com.  Meanwhile, if you have any manufacturing enquiries at plastic injection molding, or an on-going job need free design for manufacturing analysis, please feel free to contact Danke Mold via info@dankemold.com.  We will response in 12 hours.