$ErlenMeyerID_W = 30; //Widest 
$ErlenMeyerID_N = 28.5; //Narrowest
$ErlenMeyerID_L = 22; //Length

$GGTaper_W = 19;
$GGTaper_L = 22;
$GGTaper_N = 16.8; //http://www.magafor.com/841/uk.htm 1:10 taper

difference()
{
cylinder(h=$ErlenMeyerID_L,d1=$ErlenMeyerID_W,d2=$ErlenMeyerID_N,center=true,$fn=100);
cylinder(h=$GGTaper_L,d1=$GGTaper_W,d2=$GGTaper_N,center=true,$fn=100);
//cylinder(h=$ErlenMeyerID_L+1,d1=$GGTaper_N,d2=$GGTaper_N,center=true,$fn=100);
}