I have never built a bow without heating it. Riser glue ups 120 degrees max. for 2 to 3 hrs.. Limbs or full lgth. bow 160 to 180 degrees for 4 hours then let cool for 4 hrs it the box. I have not had a bow fail using this method and hope I never do. Built my first bow in 1973 with this method and it still shoots today. Back then fiberglass came in colors of black, white, brown and green. No clear, and it had a peal off backing with a weave under it and I used Urac 185 as a glue. Urac in not sutable for gluing up limbs without the weave type glass. Urac is a great glue for wood to wood but not if you use glass or micarta in the riser for accent stripes. Just my 2 cents worth.