Going off some things mentioned in the “clark foam is over” thread, what are some of the basic changes a shaper should make in respect to curves etc when comparing a PU board to EPS?
If you use 2# EPS or more, and just plan on laying up glass, you don’t have to change much at all in the curves. You can usually go 1/4 to 1/2" thinner than your PU shape would be so that it flexes.
Using 1 or 1.5#, go thinner and add extra layers of glass top & bottom. Otherwise it’ll be corky. Pinch the rails a little more too, so they can be buried if needed. But your templates & rockers will be fine.