PM Sent.
If you download a program called OpenSCAD, it's no more complicated than this bit of code:
$fn=32;
module blade(){
linear_extrude(twist=-120,height=5,slices=$fn*2,center=true) square([0.5,10]);
}
module blades(numblades){
deg=360/numblades;
for (i=[0:numblades-1]) {
rotate([0,0,deg*i])render()blade();
}
}
module whole(){
union(){
intersection(){
blades(5);
rotate_extrude(center=true)translate([5,0,0])scale([1,0.3,1] )circle(r=5,center=true);
//cylinder(r=20,h=1,center=true);
}
cylinder(r=2,h=5,center=true);
}
}
whole();