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Example: Back Spotting
The following illustration shows an example of setting up a Back Spotting tool based on geometry to be machined, and specifying the start and end depth for a Back Drill NC sequence.
1. Specify the following values for the tool parameters:
Cutter_Diam 2.4
Length 4
Csink_Angle 30
Cutting_Offset 0.4
Body_Diameter 1.3
Insert_Length 0.6
2. Select the hidden surface (1) as start surface.
3. Type an offset value of 0.75 to specify drilling depth.
The resulting sequence of tool motions is shown in the following diagram.
For Back Countersink drilling, you have to specify a start surface and a countersink diameter, similar to regular countersink drilling. The illustration below shows a Back Countersink NC sequence performed with the same tool as in the previous example.
1. Select face (1) as the start surface (similar to the previous example).
2. Type 2.2 for countersink diameter.
You can also use the Auto Chamfer option for Back Countersink drilling, in which case the system will automatically include all holes with chamfers that can be machined with the current tool, that is, with the chamfer angle corresponding to the Csink_Angle of the tool.