I am about halfway in building a 16 foot high tower made of simple bricks. It is basically a hollow skyscraper 6 inches square, with the walls two studs thick. To steady it, it is built around a steel pole anchored top and bottom. I've built it up row by row, but now given its height, I want to assemble sections of it on the ground and add them to the top. Each section is about 10-15 rows high, same square footprint. But I have unable to add sections of more than 2 rows at once. With larger heights I can not seem to apply enough pressure to get the bottoms to seat on top of the last built row. The lego are so precise that tiny displacements can't seem to be overcomed. The added bulk piece just won't marry the lower piece, unless I add them a row at a time.
How are extremely large Lego sculptures made? Are they just made by adding pieces row by row incremently? Or do they have a way to add an assembled piece to an existing piece? I even tried using plates on top row and a plate on the bottom row of new piece but could not get the plates to marry with more than a few rows on top. Any suggestions?