Everything went just perfect everything from cutting the triangles to making the base ring, I was amazed about the size, it's huge. Five persons can easily stand in it at the same time.
I decided because of the rainy winters here in sweden to cover it with boat epoxy to give it maximum protection against rain and then I put on the stucco, following your description on mixing it was a piece of cake.
Because I don't have to worry about it being waterproof I put on 2 layers
of silicon reinforced mortar paint and viola it's finished. This
was probably the largest project I've done and so far it's still standing
, and having increased my astronomical observations 200%. ( I submit some
photos of it)
So I wanted to thank you again for your help .