Cavity
Cavity is the upper half of the injection mold usually the show surface of the finished product but is mainly concave.
Molds are designated as a single cavity or multi-cavity. The lower half of the mold is called CORE.
Cavity in mold design
Below are photos to show the cavity(s) in mold designs.
Cavity in actual plastic molds
Below are photos to show the cavity(s) in actual injection molds.
Cavity in design for manufacture
Plastopia use different cavity steel for specific production life. Below is a list for the mold steel we frequently use.
You will be also see them in our quotation.
Cavity steel
Plastopia use different cavity steel for specific production life. Here is a list for the mold steel we frequently use.
You will be also see them in our quotation.
| Material | Applications | Rockwell Hardness | Surface Finish |
| H-13 Steel | Post-hardened steel for high volume molds | 48-52 Rc | Up to SPI A-1 |
| Nak 80 Steel | Pre-hardened tool steel for middle volume molds | 38-41 Rc | Up to SPI B-2 |
| P-20 Steel | Pre-hardened tool steel for middle volume molds | 28-32 Rc | Up to SPI B-2 |
| 718 Steel | Tool steel for low volume molds | 28-32 Rc | Up to SPI B3 / C-1 |