Thank you Gaieus, Remus and Anssi,

It's surely the co-planar surface problem (Z fighting) since I remember re-drawing the same surfaces somewhere. Will re-examine the drawing and find out.
Thanks a lot
Bye
Mario

Hello Folks,
Quite often I get triangular flashes of colour, strange shapes, etc. that force me to move back and find some angle that moves them out of sight.
Can you tell me what causes them, what I may be doing wrong, etc ?
Thanks
Mario

Thanks a lot Jim, you'll have understood that I am a beginner with Sketchup. Have already tried your suggestion and solved the problem.
I understand that Dynamic Component is supplied with the more professional Sketchup version and would make things easier.
An incentive to purchase in the next future I hope.
Bye
Mario

Hello everybody,
So far to obtain wavy valances for awnings I must go through an endless repetition of the Arc command.
I've tried saving a valance as a component but since shapes and dimensions change with each face and awning it is not practical.
Can anyone advise about how to obtain such shapes by using a more functional and less time-consuming method??
Thanks
Mario