Model barns. Round roif

[Pramjils]

What is a good way to construct 2/32 round barn roofs. 

[Anderson Agri]

When i did one, i used a 2l coke bottle and rolled corrugated card around it and it seemed to hold shape after a while. Then glued it to a frame to keep the strength,

 

[Pramjils]

Thanks for reply. Will try this