Cooling of mould
What is the pros and cons of cooling a mould in water after injection/ compression?
Probably depends on a lot of factors – type of plastic, dimensions and shape of mould, etc…
I know for HDPE and PP, and probably others, the faster you cool, the less crystallization that occurs. This results in slightly weaker, but less brittle plastic.
If cooling is uneven, you can end up with warpage. Even if the mould remains in pressure to keep shape, the side that cools slower will be more crystalline than the other side, which can result in different internal stresses.
Only one way to really find out – just start tinkering.
another factor is the thermal stability of the mould. as the metal the mould is made of heats up, the size increases slightly, which leads to a larger finished part, probably not a huge problem if you are just making a planter stand or similar low precision part, but worth keeping in mind nonetheless
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