// -*- C -*-

holedist = 64;
tonguewidth = 10;
tongue2width = 15;
totaldepth = 26;
tongue2depth = 35;
thick = 4;
tabover = 7;
tabunder = 15;

tabside = 7;

tonguethick = 4;
tongue2thick = 5;
strapthick = 2;
strapwidth = 5;
ridgewidth = 2;

holedia = 3.5;

tongue2x = tongue2width - holedist;

module Tongue(tw,tt,ad,slots=2){
  y0=thick+0.1;
  yn=ad-ridgewidth-strapwidth;
  difference(){
    translate([-tw, 0, 0])
      cube([tw, ad, tt+strapthick]);
    for (yi=[0:slots-1])
      translate([-tw-1, y0 + (yn-y0)*yi/(slots-1), tt])
	cube([tw+2, strapwidth, strapthick+1]);
  }
}

module Object(){
  difference(){
    translate([-holedist-tabside, 0, 0])
      cube([tabside*2+holedist, thick, tabunder+tabover]);
    for (x=[-holedist,0])
      translate([x, -1, tabunder])
	rotate([-90,0,0])
	cylinder(r= holedia/2+0.5, h=thick+2, $fn=20);
  }
  Tongue(tonguewidth,tonguethick,totaldepth,3);
  translate([tongue2x,0,0])
    Tongue(tongue2width,tongue2thick,tongue2depth+thick,4);
}

Object();