Openscad union not working like I thought it might

General
1

I have written a little openscad to create a gear that I wish to cut on my CNC machine.

Code: Select all

$fn=75;
GearRatio = 4;
PinionTeeth = 8;
ToothWidth=3.1;
ToothHeight=3;
ToothSlope=0.6;
eps = 0.01;
module Tooth() {
    polygon([[0,0],[0,3],[1.5,3],[3.1,2.4],[3.1,0.6],[1.5,0],[0,0]]);
    }
module BoltHoles() {
    for (BoltHole=[0:120:360]) {
        rotate([0,0,BoltHole])
        translate([0,12,0.1])
        circle(d=3.5);
    }
}
module BaseCircle() {
    difference() {
        circle(d=52);
        circle(d=18);
        BoltHoles();
    }
}
module Base() {    
    angle=(360 / (GearRatio * PinionTeeth));
    union() {
    BaseCircle();
    for (Step=[0:angle:360]) {
         rotate([0, 0, Step])
         translate([25.9,-1.55,0])
         Tooth();
        }
    }    
}
        
difference() {
    linear_extrude(6) Base();
    for (BoltHole=[0:120:360]) {
        rotate([0,0,BoltHole])
        translate([0,12,3.1])
        cylinder(h=3,d=5.5);
       }
   }

Bringing this into freecad I would expect the polygon’s around the circle to become one with the circle for it is enclosed by a union().
It does not and the polygons get cut individually. Please tell me how I can fix this?

2

My lack of Freecad knowledge caused the problem. Using PATH and how to correctly select in Freecad was the issue. Not Openscad.

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