1. Choose Material for Mold Core (Note: Chinese often use imported steel for mold core)
I: Life Span: 0.5 to 1 million injections
Japanese NAK80 ( *popular choice ),
mirror finish, good for product that requires high transparency or surface quality. Similar to AISI P20+Ni, German 2738, Swedish 718 (cheaper).
II: Life Span: 1 million injections. Good for corrosive plastics (PVC,POM)
Swedish S136, expensive, mirror finish, good for product that requires high transparency or surface quality. Similar to AISI 420
German 2083/2316 (a lot cheaper)
III: Life Span: only 100 thousand to 300 thousand injections
American AISI P20 ( *popular choice ), much cheaper than NAK80 or S136. similar to Swedish 618/V007.
IV: Life Span: only good for a few thousand injections
AISI 1045,1050, the cheapest, product have rough surface, dimensions will not be precise, not recommended.
2. For mold core, use
(Cheaper)
3. Distance between cavities: (Applicable for multple cavity mold, 2.5-4.5cm) (larger than 1.5 cm) 5. Top of product to top of mould core
(usually larger than 1 cm) 6. Bottom of product to bottom of
mould core
(usually larger than 1.5 cm)
7. (common choice, "three-plate mold", higher production speed, less distortion after mold) (cheaper, "two-plate mold",cheap,need secondary process to cut plastics attached from gate)
8. Hot runner system needed? If yes,how many points per
cavity?
(usually 1~2)
(Hot runner system reduces material waste and improves production efficiency and quality for large complex product.
It's expensive.)
9. Production Cycle:
( sum of 2-5 seconds injection time, 20-120 seconds to
hold pressure and 30-120 seconds cooling. This
setting affects product price but not mold price)
