Re: Fletcher Arrow
I can't really remember, but I think it expands 10/1 to 20/1. We used it in 2005.
Manufacturer is Scott Bader Co Ltd, Wellingborough, NN29 7RL 01933 663100, perhaps they can provide a spec. sheet.
If I am right, all your foam will be above the deck/floor. If you could cut and sandwich Kingspan/Xtratherm or similar polyurethane foam sheet to fit and wedge or strap it VERY FIRMLY in place, I would consider that instead.
Windshield. We made one out of Polycarbonate sheet, and heat moulded it (using old radiant electric bar fires), bending it over a former made of corrugated cardboard. It wasn't perfect, but good enough for our project. The main risk is that Polycarbonate is hygroscopic (absorbs water), and it need to be heated to a bit below 100C for a day or so before heating to over 100c for bending, otherwise lots of little bubbles will appear in the sheet. Piccy attached of finished article, bonded to the boat by a wide strip of old tyre inner tube and cyano.
Hope this helps,
O-G