This is the thread I was looking for last year and couldn't find it again.
I saw the pictures in passing and was looking at how you are finishing the edges of the plexi on the router table. That method has to be the most unsafe method ever of finishing off an edge.
Like most fabrications with tools and materials, there are many methods or ways to complete an operation. Any and all power tools can be and are dangerous if not used poperly.
The operation you are talking about is done this way for a specific reason!
By using this method to SIZE the sheets. you end up with in this case 4 sheets that are all EXACTLY the same size in height.
No other way to do this.
The real fun is when you do this with 1" thick sheet material that weighs 200 lbs and cost big $$$$ . The HOBBY table saw / router table you see in pictures can not complete that work with the precision required.
A 4'x8'x2" thick router table with 4ft and 8ft fences is used, and yes you have to trap the material in order to mill it to exact size. Takes time and care but imho its easy and safe as any other shop operation.
You want to see some unsafe shop work stay tuned. Making small parts with big power tools is imho the dangerous work. Milling big sheets of plastic is easy and safe compaired