Quoted from ravve:Ok, thanks. I suppose u mean ball hangs between the protector edge and playfield? But as I am designing it myself, I figure I can make the cutting so that it goes all the way to wood, covering the whole playfield, unlike a traditional protector that has larger hole cuts to perhaps make installation easier?
Then again, I am only speculating as I never done any protector instals before.
The reason for the large hole cut outs is not just to make installation easier. Plastic expands faster than wood when it heats. If you have the plastic protector go underneath all of the posts, it will be fastened down to the playfield in many places and will not be able to expand and contract. I tried this once and the plastic protector literally bowed upward in the middle of the playfield after the game warmed up. There was at least a half inch gap if not more between the protector and the playfield. This cause the ball to roll like a roller coaster. Rather than re-cut the plastic, I replaced every bulb in the game (it was a Bally EM) with LEDs to cut down on heat. I also put in powerful fans drawing air into the game which created airflow through the cabinet and out the backbox. That made it so the game never heated up at all inside when it was being played and successfully prevented the protector from rising off the playfield.
So a big part of making a plastic protector is making it so that it is not screwed down. It needs to be able to be slid a couple of mm in each direction or you will have problems. In general, I would also make sure the game is 100% LEDs anyway.