- translate([botleft[0], botleft[1], 0])
- cube([size[0], size[1], tile_th]);
- translate( [ botleft_post[0], botleft_post[1], -tile_th ]
- + 0.5 * [ post_dia, -post_dia, 0 ] )
+ translate(concat(botleft, [0]))
+ cube(concat(size, [tile_th]));
+ translate( concat(botleft_post, [-tile_th])
+ + 0.5 * [ post_dia, post_dia, 0 ] )