I started discussing this idea in MDF first of all in the CAD forums 2D Drawings Gallery - Tessellated I - my simple technical drawing, coloured artfully - because initially I only had computer graphics images to show for my efforts - but I didn't get any replies to my topic there. At last I have a physical model made and some real images and a video to show you so, being as how that's not really a 2-D drawing nor a CAD image of any kind, I am starting this new topic in the main design forum to see if anyone here will reply? 3-Dimensional model video Tessellated I or H bricks and tiles for stronger, lighter assembled structures (YouTube) This video shows my model of the 3-dimensional shape of a simple structure composed of 6 bricks or tiles, each of which, when viewed from one-direction anyway, are a 2-dimensional "I"-shape (equally when rotated by 90 degrees "H"-shaped). This model has been made from aluminium tubing and in order to distinguish one brick from another they have been coloured using marker pens - so there are two bricks coloured blue, two coloured green and two coloured red. This colouring was necessary for clarity because otherwise the permanent joints within bricks (which are only an artifact of the method to make a brick from square tubing) might be confused with the simple touching surface where two neighbouring bricks abut, abutting securely but without being in any way stuck by glue etc. This 3-Dimensional model reveals a further design feature of the I or H brick and tile structures, which secures the bricks and tiles together in 2 further dimensions, some such feature being necessary because the 2-D I or H shape in of itself only secures the bricks together in 1 dimension. This feature is revealed here to be nothing more complicated than dowels or fixing rods which run in the vertical direction of the Is (or the horizontal direction of the Hs) through shafts in the Is' bases and tops and which serve to lock the tops and bases of neighbouring Is together, preventing movement radially from the dowels. These dowels may henceforth be referred to as "Mazurka Dowels" named after the username of a scientist in an internet science forum who first correctly anticipated this feature of my 3-D design and its function to hold the structure together in all 3-dimensions, in a reply post to my topic there describing in detail only the 2-D tessellation, suggesting somewhat vaguely that some such design element was required for a good 3-D design with a view to seeing who would suggest the solution I had thought of first. As I explained in that topic I could hardly call those dowels the "Dow dowels" there being too many dows in that name and anyway, my name can be used to reference this particular shape of I or H tile and brick and structures composed of them, as per "Dow tile" "Dow brick" "Dow I-tile" "Dow H-brick" "Dow I-H-brick" "Dow I-H-brick structure" "Dow I-structure" etc. I did mention possible materials and applications in the other topic in the 2-D drawing gallery forum if anyone wants to contribute ideas here or there about any of that I'd welcome your input. Thanks.