hello,
i am dasol who are making a plastic product in korea.
I’m trying to understand which type of plastic can easily make and safe and there are three things which are PP, HDPE, PET

Basically, my heating process is that I heated first and put it out from the oven, and mixing and compressing.
with this kind of process, PP, HDPE is good enough. but there is one problem about flat.

you can see the picture, the face is rugged not flat.
i’d like to ask about this to all of plastic armies!
how should I make it flat? is it heating problem? or compressing problem?

also, PET is very hard to press with out heating.
when is put out from the oven, it’s going to hard very fast.
do you have any idea of make PET still melt when it put out from the oven?

i am looking forwards your response.
thank you for reading.

Dasol