Question about pressing a warped board flat: 8 hours under weights vs 30 minutes with a heat gun
I had a 6 by 9 inch cover board that warped after I glued on the spine cloth last Tuesday in my garage in Dayton. First I stacked about 40 pounds of old textbooks on it for 8 hours. Still bowed, maybe a quarter inch gap at the corners. Then I tried my heat gun on low from about 10 inches away, 30 minutes total with a flat board on top. Dead flat, no scorch marks. The heat softened the glue just enough to let it settle. The weights alone could not pull it back because the glue had already set cold. Has anyone else had luck with heat instead of long pressing for small warps? I am worried it might make the board brittle down the road, so I want to hear if this bites me later.