kerf = 0.02;
thickness = 0.17;

sf = 96;

squareSize = 2 + kerf;
ligatureWidth = 0.75;

desiredSpacing = 0.125;
slotLength = 0.5 - desiredSpacing / 2;

chamferSize = 0.05;

mm_per_inch = 25.4;

module slotCutout() {
    square([thickness - kerf, slotLength * 2], center=true);
    rotate([0, 0, 45]) square(thickness - kerf + chamferSize, center = true);
}

module squarePiece () {
    difference() {
        square(squareSize, center=true);
        for(i = [0:3]) {
            rotate([0, 0, 90 * i]) translate([0, squareSize/2]) slotCutout();
        }
    }
}

module straightLigature() {
    intersection() {
        squarePiece();
        square([squareSize, ligatureWidth], center=true);
    }
}

module xLigature() {
    union() {
        straightLigature();
        rotate([0, 0, 90]) straightLigature();
    }
}

module lLigature() {
    ss = squareSize - (squareSize - ligatureWidth) / 2 ;
    intersection() {
        xLigature();
        translate([(squareSize - ss) / 2, (squareSize - ss) / 2]) square([ss, ss], center=true);
    };
}

module tLigature() {
    ss = squareSize - (squareSize - ligatureWidth) / 2 ;
    difference() {
        xLigature();
        translate([0, -ss]) square(squareSize, center = true);
    }
}

scale([sf, sf]) translate([1, 1]) {
    
    translate([0, 0]) squarePiece();
    translate([20, 12]) xLigature();
   
    for(x = [0:5]) for(y = [0:3]) {
       translate([x * 2.125, y * 2.125]) squarePiece();
    }
    
    translate([12.25, 6.375]) rotate([0, 0, -90]) for(x = [0:3]) for(y = [0:5]) {
       translate([x * 2.125, y * 0.8625]) straightLigature();
    }
    
    translate([-0.625, 12.375]) rotate([0, 0, -90]) for(x = [0:2]) for(y = [0:3]) {
        translate([x * 1.8, y * 2.5]) {
            lLigature();
            translate([0.875, 1.5]) rotate([0, 0, 180]) lLigature();
        }
    }
    
    translate([10, 8.125]) for(x = [0:3]) for(y = [0:1]) {
        translate([x * 2.25, y * 2.375]) {
            tLigature();
            translate([0.875, 1.5]) rotate([0, 0, 180]) tLigature();
        }
    }
    
    translate([20, 0]) for(x=[0:0]) for(y=[0:4]) {
        translate([x * 2.125, y * 2.125]) xLigature();
    }
    
};