Hi Roger. I cannot remember if I discussed this issue with you at Tokoroa but thanks for the link as it confirmed how the hinging is finished at the factory. As the commentary says the builder must be careful not to cut too deep and this confirms what I thought after inspecting the wreck. All the hinges had cleanly parted along the line without any other signs such as any delamination or pulling out. The material is some type of woven fabric..
With so many models flying successfully with these type of hinges makes me believe the material is ok as long as it is not cut or scored during manufacture.................Ron