If you are a small repair shop owner, and you have a lot of different models of phones to repair, you will feel that it is very annoying when you need to change the metal molds again and again.
There is a good news in the engineering improvement that I have to tell you.
You will not need a metal mold for the grid to grid glass laminator, instead of a metal mold, you just need some plastic molds like the following
You can use a plastic mold for the alignment, put your LCD in the plastic mold, put the OCA on the glass, and peel off the OCA protective film, then put the glass on the LCD and press a little bit to make sure the OCA stick to the LCD, then they basically become an unit, you can put it between 2 soft airbags under the vacuum environment.
This kind of plastic mold is much cheaper than the metal mold, one plastic mold is around 4 USD, it is very affordable.