Design Guidelines: Overmolding & Insert Molding
Our basic guidelines for overmolding and insert molding include important design considerations to help improve part manufacturability, enhance cosmetic appearance, and reduce overall production time.
Size
Maximum Dimensions
| SIZE | 18.9 in. x 29.6 in. x 8 in. |
|---|---|
| VOLUME | 59 cu. in. |
| DEPTH | 4 in. from parting line |
| Up to 8 in. if the parting line can pass through the middle of the part | |
| PROJECTED MOLD AREA | 175 sq. in. (plastic) 48 sq. in. (silicone rubber) |
| SIZE | 480mm x 751.8mm x 203.2mm |
|---|---|
| VOLUME | 966837 cu. mm |
| DEPTH | 101mm from parting line |
| Up to 203.2mm if the parting line can pass through the middle of the part | |
| PROJECTED MOLD AREA | 112903 sq. mm (plastic) 30968 sq. mm (silicone rubber) |
Height may be limited if using a silicone as the overmold material, and deeper parts are limited to a smaller outline. Minimum part volume is 0.025 cu. in. (40.98 cu. mm). With substrate molds, we can maintain a machining tolerance of ±0.003 in. (0.08mm) with an included resin tolerance that can be greater but no less than 0.002 in./in. (0.002mm/mm). With thermoplastic overmolds, tolerances remain the same as substrate molds, however, if the overmold is LSR, then tolerances shift to 0.025 in./in. (0.025mm).
Insert Molding Capabilities
Instead of a mold that produces a final part using two separate shots like ovemolding, insert molding generally consists of a preformed part—often metal—that is loaded into a mold, where it is then overmolded with plastic to create a part with improved functional or mechanical properties. We currently accept inserts from PEM, Dodge, Tri-Star, Spirol, and Tappex. A complete chart of stocked inserts at Konlida is available here.
One way insert molding is used is with threaded inserts, which reinforce the mechanical properties of plastic parts’ ability to be fastened together, especially over repeated assembly. Bushings and sleeves are another great way to increase part durability for mating components that need more abrasion resistance due to moving parts.
