Step 6: Construction 6
The lenses of the safety glasses are polycarbonate which means you can cut a square hole out of one of them with a Dremel with a cutting disc in it and the lens will not shatter.
Measure twice, cut once. I marked up the square hole using black insulation tape strips and then moved them around over and over until exactly right before cutting anything.
I glued thin clear plastic to sides of prism and then cut them down little by little so that when they were stuck to lens of glasses the prism was held at exactly the right angle for you to see the screen properly while wearing the glasses. This stage needs to be done very slowly and carefully in small increments to get it right.
I used plastic glue very sparingly in places and a hot melt glue gun also (with care).
Once the prism unit was mounted I reassembled the display components back into the top of it. It all clips together although very delicate. Tiny blobs (and I mean really tiny) of hot melt glue stop it coming apart when assembled.