I have made eggs with large paper mache base (both Hobby Lobby and Michaels and other craft stores carry the blank brown paper molded eggs, large and small). The large ones gave me a little bit of a problem because the clay shrank more than the base and they tended to crack. I was a little worried that the polymer clay would shrink around this ostrich egg and show cracks as well.
Before I cured this egg i did use my blade to put a hairline cut down some portions of the pattern hoping to encourage the clay to split there so that I could repair it as part of the design. In fact however, the polymer clay did not shrink over this base…. I do not know why there was a difference in the brown paper egg and the ostrich egg, but that was my experience (again, a first try). You can have a custom ostrich egg, flower petal, polymer clay cane ostrich egg, to purchase HERE.
