Did the wood break across the panel or split length wise?
Your panel may have been stronger if the strips were parallel to the edges. I understand why you didn't and you probably would have had no issue with the way you did them if one side would have been glassed before or after you cut the panel to shape. Not knowing the exact shape you wanted may have made that impractical.
I love cedar because it is so pretty and light weight. It is brittle and not very strong. Finding clear wood is also hard. Fiberglass and epoxy can make it doable, almost required.
Your panel may have been stronger if the strips were parallel to the edges. I understand why you didn't and you probably would have had no issue with the way you did them if one side would have been glassed before or after you cut the panel to shape. Not knowing the exact shape you wanted may have made that impractical.
I love cedar because it is so pretty and light weight. It is brittle and not very strong. Finding clear wood is also hard. Fiberglass and epoxy can make it doable, almost required.