OpenSCAD Custom Shim Generator

shim.scad

/*
  This script generates a custom shim based 
  on the given parameter values
*/

$fn=50;

internal_diameter=4;
external_diameter=8;
height=4;

Shim(internal_diameter, external_diameter, height);

module Shim(int_diam, ext_diam, height){
    assert(int_diam < ext_diam);
    assert(height > 0);
    
    difference(){
    cylinder(h=height,d=ext_diam);
    translate([0,0,-1]) cylinder(h=height+2,d=int_diam);
    };
}