Radial Tessellation

ilox_radial places interlocking cell pairs on a hexagonal lattice with rotational symmetry: cell A instances (green) sit on hexagon centers over one substrate, cell B instances (blue) on the triangulated midpoints under the other, so pressing the two substrates together engages every cell at once.

Source: examples/simpleUsage/simpleUsageRadial.scad

use <../../iLOX.scad>;

// Width / height of the unit cell
width = 5;
height = 10;

// Division line as [x, y] points
div = [ [ 0.5, 0 ], [ 0.3, 0.1 ], [ 0.3, 0.4 ] ];

// Gap between the interlocking cells, in mm
clearance = 0.2;

// Voids cut out of the cell: a list of polygons
voids = [ [ [ 0.7, 0.8 ], [ 0.7, 1 ], [ 0.3, 1 ] ] ];

// Rings of hexagons in the lattice
levels = 4;

ilox_radial(width = width, height = height, div = div, clearance = clearance,
            voids = voids, levels = levels, part = "both");

Key parameters:

div — the division line that splits the unit cell into the two interlocking halves.
clearance — the gap between the two halves in mm, measured normal to the division line. A feature of the line too small for the clearance, such as a barb narrower than it, is lost in the offset, and the gap there is wider.
tip_clearance — optional gap between each cell’s tip and the opposite substrate, in mm, below half the cell height; defaults to clearance, and 0 gives full-height cells. A large value can cut a cell short of interlocking, and a clip just above a horizontal face can leave a thin ledge.
part — "both" to view the joint, or "A" / "B" to export one printable half (print B upside down).
levels — how many rings of hexagons the lattice grows outward; at least 2, since the B cells sit between the A cells.

Each cell is a hexagonal extrusion of its half of the unit cell, and each B cell faces three A cells one width apart, across flat sides, so the gap between them is clearance as in the 2D cell. Cells of the same half sit corner to corner, √3 × width apart, so a cell whose profile reaches past 0.75 × width merges with its neighbours into one web.

Set show_ucell = true in the full example file to inspect the 2D unit cell with ilox_cell_designer before tessellating it.