d_outer = 9.3;
d_inner = 7.5 ;
b_nase = 1.4;
h_nase = 2.5;
p_nase = 1.5;
h = 6;
r_bitting = 2.65;

d1 = 3;
d2 = 1;
d3 = 2;
d4 = 2;
d5 = 3;
d6 = 2;
d7 = 1;

$fn = 100;
difference(){
cylinder(h=h+6,r = d_outer/2);
cylinder(h=h,r = d_inner/2);   
translate([4,4,0])cylinder(h=d7,r=r_bitting);
translate([-4,4,0])cylinder(h=d1,r=r_bitting);
translate([-4,-4,0])cylinder(h=d3,r=r_bitting);
translate([4,-4,0])cylinder(h=d5,r=r_bitting);
translate([5.7,0,0])cylinder(h=d6,r=r_bitting);
translate([-5.7,0,0])cylinder(h=d2,r=r_bitting);  
translate([0,-5.7,0])cylinder(h=d4,r=r_bitting);      
}
translate([0,d_outer/2+p_nase/2-0.1,h_nase/2])cube([b_nase,p_nase,h_nase],center=true);
translate([0,0,h+6])cylinder(h=4,r = d_outer/2+1.5);