ROBO 3D R1+ clamps for no glue, no hairspray build plate

These are quick connect 'clamps' to hold down what I consider (at this point) the ultimate build plate.

These clamps go on the back of the glass plate and secure the added plate in place (as seen in the photos)

Intrigued by the build plate types like the Fleks 3D, but being cheap - I read in one review about using Lexan. So, I picked up a couple of sheets (11x14 @ ~$8ea) at my local Homedepot and did some testing.

I found that using a orbital sander with 100 grit paper and 'roughing' up