How to create Involute gear profile

This is some parts from my sources for mill's profile creation,
i hope they will be helpful for you

Spline creating example:

TColgp_Array1OfPnt2d array_zub_1 (0,8);
for (int n = 0; n < 9; n++) {
pt_spl = arhspoint(
pt_c,
(M_PI/2.0),
ra,
(k1*z),
teta
);
teta += step;
array_zub_1.SetValue(n,pt_spl);
}
Handle(Geom2d_BSplineCurve) spline_zub_1 =
Geom2dAPI_PointsToBSpline(array_zub_1);

Segment creating example:

Handle(Geom2d_TrimmedCurve) segment_zub_1 = GCE2d_MakeSegment(
arhspoint(
pt_c,
(M_PI/2.0),
rats,
(k2*z),
teta
),
pt_lzr);

Arc creating example:

gp_Circ2d circle_zub_1(gp::OX2d(), r);
circle_zub_1.SetLocation(pt_cr);
Handle(Geom2d_TrimmedCurve) arc_of_circle_zub_1 =
GCE2d_MakeArcOfCircle(circle_zub_1, pt_lzr, pt_rlp, Standard_True);

Creating mill's profile:

TopoDS_Edge edge_zub_1 = BRepBuilderAPI_MakeEdge2d(spline_zub_1);
TopoDS_Edge edge_zub_2 = BRepBuilderAPI_MakeEdge2d(spline_zub_2);
TopoDS_Edge edge_zub_3 = BRepBuilderAPI_MakeEdge2d(segment_zub_1);
TopoDS_Edge edge_zub_4 = BRepBuilderAPI_MakeEdge2d(arc_of_circle_zub_1);
TopoDS_Edge edge_zub_5 = BRepBuilderAPI_MakeEdge2d(segment_zub_2);

BRepBuilderAPI_MakeWire wire_zub;
wire_zub.Add(edge_zub_1);
wire_zub.Add(edge_zub_2);
wire_zub.Add(edge_zub_3);
wire_zub.Add(edge_zub_4);
wire_zub.Add(edge_zub_5);

Creating complete profile:

BRepBuilderAPI_MakeWire wire_profile;
Standard_Real ang_step = 2.0*M_PI/frdata.int_z0;
gp_Ax1 axis_z(gp_Pnt(0.0,0.0,0.0), gp_Dir(0.0,0.0,1.0));

for (int n = 0; n < frdata.int_z0; n++) {
TopoDS_Wire wire_rotated;
gp_Trsf transform;
transform.SetRotation(axis_z, ang_step*n*-1);
BRepBuilderAPI_Transform brep_transform(wire_zub, transform);
TopoDS_Shape rotated_shape = brep_transform.Shape();
wire_rotated = TopoDS::Wire(rotated_shape);
wire_profile.Add(wire_rotated);
}

I can mail you complete sources (GPLv2) for creating
mill's profile and building 3d model of the mill:)

P.S.: Sorry for my english :(

Hi All,
There is a good tutorial which shows step by step, how to create an involute gear using parametric modeling in CATIA V5.
Refer link http://gtrebaol.free.fr/doc/catia/spur_gear.html
The parametric equations and procedure can be very well adopted to Open CASCADE function calls. I have used the tutorial to create in CATIA. I have not used it for Open CASCADE but I am sure this can be very well adopted for programming too. Hope this helps.

Regards
N. Sharjith