thanks for replies :D i have messed about with some of your suggestions and stumbled on a solution that works for me, it all seems a bit random but im sure there is a method in the way you lay the four blocks, whether left to right then drag towards yourself or right to left or any of the other poss...

hello :) my sons use sandbox quite a lot and are pretty good at creating some amazing stuff(for their age) but we have tried to hollow out a pyramid and it always deforms. we have tried many approaches to achieve it but always it always goes wrong, the wiki has a listing for hollowing out a pyramid ...