$fn = 40;
// this is not a proper drawing yet, but it should be a working universal joint for 5 mm shaft
base();
//translate([0,0,25])rotate([0,180,90])base();
//translate([0,0,12.5-5.3/2])connector();
// the parts:
module base() {
  difference() {
    intersection() {
      union() {
          
        cylinder(d = 10, h = 7.5);
        translate([-5, -2.5, 0])cube([10, 5, 12.5]);
        translate([-5, 0, 12.5])rotate([0, 90, 0])cylinder(d = 5, h = 10);
      }
      cylinder(d = 10, h = 30);
    }
    cylinder(d = 6, h = 7.5);
    translate([-2.7, -5, 6.5])cube([5.4, 20, 20]);
    translate([-5, -5, 7.5])rotate([0, 90, 0])cylinder(d = 5, h = 10);
    translate([-5, 5, 7.5])rotate([0, 90, 0])cylinder(d = 5, h = 10);
    translate([-5, 0, 12.5])rotate([0, 90, 0])cylinder(d = 2, h = 10);
    translate([-5, 0, 3])rotate([0, 90, 0])cylinder(d = 2.5, h = 10);
  }
  difference(){translate([0,0,-16])cylinder(d=10,h=16);
  translate([0,0,-16])cylinder(d=6,h=16);
       translate([-5, 0, -12])rotate([0, 90, 0])cylinder(d = 2.5, h = 10);
  }
}
module connector() {
  difference() {
    hull() {
      cylinder(d = 5.3, h = 5.3);
      translate([-5.3 / 2, 0, 5.3 / 2])rotate([0, 90, 0])cylinder(d = 5.3, h = 5.3);
      translate([0, 5.3 / 2, 5.3 / 2])rotate([90, 0, 0])cylinder(d = 5.3, h = 5.3);
    }
    translate([-5.3 / 2, 0, 5.3 / 2])rotate([0, 90, 0])cylinder(d = 1.6, h = 5.3);
    translate([0, 5.3 / 2, 5.3 / 2])rotate([90, 0, 0])cylinder(d = 1.6, h = 5.3);
  }
}