Compression Machine

I have a question about the compression machine (oven)

How much pressure do you add with the jack? And I guessing that as the plastic melts you keep turning the jack to add pressure?

So I was thinking if we added weights to the top of the frame so it pushed down rather than up, the pressure would be added slowly and constantly and there by making it a set and forget process.

Also could you add multiple moulds to the oven at the same time there by getting more output for the same energy input?

Great questions! It is a pity that nobody has answered them.
(trying to get someone to respond now)