hextile.scad

a = cos(60);
b = sin(60);
z = 0.25; // inset to connections, larger is looser. 0.2
w = 7;
hex_tile = [
  [(-1+z)*a,(2*w-1-z)*b],
  [w+(-1-z)*a,(2*w-1-z)*b],
  [w+(-2)*a,(2*w-2)*b],
  [w-z-1+(-2)*a,(2*w-2)*b],
  [w-1+(w-2-z)*a,(w-2-z)*b],
  [(w-1)+(w-z)*a,(w-z)*b],
  [(w-1)-z+(2*w)*a,0],
  [(w-2)+(2*w)*a,0],
  [w-2+(2*w-1-z)*a,(1+z)*b],
  [w-2-z+(w-1)*a,(-w+1)*b],
  [w-z+(w-1)*a,(-w+1)*b],
  [w-(1+z)*a,(-2*w+1+z)*b],
  [w-2*a,(-2*w+2)*b],
  [w-(1-z)*a,(-2*w+3+z)*b],
  [-(1+z)*a,(-2*w+3+z)*b],
  [+(1-z)*a,(-2*w+1+z)*b],
  [-w+(1+z)*a,(-2*w+1+z)*b],
  [2*a-w,(-2*w+2)*b],
  [-w+1+z+(2)*a,-(2*w-2)*b], 
  [-w+1-(w-2-z)*a,-(w-2-z)*b],
  [-w+1-(w-z)*a,-(w-z)*b],
  [-w+1+z-(2*w)*a,0],
  [-w+2-(2*w)*a,0],
  [-w+2-(2*w-1-z)*a,-(1+z)*b],
  [-w+2+z-(w-1)*a,(w-1)*b],
  [-w+z+(-w+1)*a,(w-1)*b],
  [-w+(1+z)*a,(2*w-1-z)*b],
  [-w+2*a,(2*w-2)*b],
  [-w+(1-z)*a,(2*w-3-z)*b],
  [(1+z)*a,(2*w-3-z)*b]
 ];

 union() {
  difference() {
    scale([1.5,1.5]) linear_extrude(height = 3, convexity = 200) {
      polygon(hex_tile);
    }
    
    translate([0,0,1]) linear_extrude(height=3)
      circle(15.25,$fn=6);
    translate([0,0,-2]) linear_extrude(height=4)
      circle(12,$fn=6);
  
    }
  /*
  r = 0.7;
 linear_extrude(height=0.5) {
    for (i = [-5:2:5]) {
      translate([1+a,i*b]) circle(r,$fn=6);
      translate([-1-a,i*b]) circle(r,$fn=6);
    }
    for (i = [-4:2:4]) {
      translate([0,i*b]) circle(r,$fn=6);
      translate([-2-2*a,i*b]) circle(r,$fn=6);
      translate([2+2*a,i*b]) circle(r,$fn=6);
    }
    for (i = [-1:2:1]) {
      translate([-3-3*a,i*b]) circle(r,$fn=6);
      translate([+3+3*a,i*b]) circle(r,$fn=6);
    }
  }
  */
}