I had 2 cracked spitfire windshields and couldn't bring myself to order a 3rd one without attempting to repair them since one was just cracked. (the other had one piece break right off and cracked the rest) After googling I found out about Acrylic Cement. Guys use it to make fish tanks out of acrylic and it works well. I bought IPS Weldon 5 Oz 16 Acrylic Cement It worked pretty well. It doesn't really act like glue, it acts more like a weld. I used it on the 2 broken windshields and I can now flex them without re-cracking them. I haven't taken a ride with them yet, but they seem to be good.