@jean lemire said: Hi folks. Here is a trick that allows a regular positioning around a circle (radial array), without any calculation. ... Just ideas. That's pretty sexy but what I had in mind was using a shaped standard size brick - much like blocks of ice Inuit cut to build igloos (at least in my mind's eye). In this case I can only envisage setting the first block of each ring (including correct tilt) and then using radial copy. The number of copies are guessed and the surplus deleted + 1/2 if any need to be cut to fit and to maintain bond. Of course you will end up with an ocular hole as discussed in other dome related topics. As you say just ideas.