How to Create a Counter Bore Hole Feature

Introduction

The counter bore example follows the same procedure as the other hole making features. The only difference is in the geometry selection. Follow this lesson to create a Counter Bore feature, toolpath, and NC program.

Example

Part 1) Open the Example File

1. Click FileOpen.
   
   

2. Select HoleExample.SLDPRT (C:\BobCAM Data\BobCAMV**\Examples\HoleExample.SLDPRT).

Part 2) Create a New CAM Job

1. Click the BobCAM Manager tab.
   
   

2. Right-click CAM Defaults, and click New Job.
   
   

3. In the Machining Job dialog box, leave Milling selected as the Job Type.
   
   Click to select the Start Stock Wizard check box.
   
   For this example we use the BC 3X Mill machine.
   
   

4. Click OK to create the Milling Job and open the Stock Wizard.
   
   

5. Click to skip assigning a Workpiece to the job and move to the Stock Specification page.
   
   

6. Under Stock Type, click Cylindrical.
   
   The Auto from Workspace option automatically detects the solid body and creates a bounding stock.
   
   Click Next to go to the Machine Setup.
   
   

7. For this example we use the default settings with the machining origin at the top and center of the stock.

 

Click OK to finish the Machine Setup.

Part 3) Add a Counterbore Hole Feature and Select Geometry

1. In the CAM Tree, right-click Stock and select Blank/Unblank to hide the stock.
   
   

2. Right-click Machine Setup, and click Mill Counterbore Hole.
   
   The Hole Wizard displays.
   
   

3. Click Select Geometry.
   
   

4. Click to select the two cylindrical faces of each of the three counter bore holes as shown next (six selections).
   
   
   
   

5. To confirm the selection, click OK.

 

Note that during geometry selection you can click the Select Whole Bodies check box and then just click the model.

 

When you select the geometry for a Mill Counterbore Hole feature, the software extracts all applicable features and creates a separate feature for each unique hole size.

 

Tip: After inserting a Counter Bore feature, you can modify the assigned feature geometry by right-clicking Geometry and clicking Re/Select from the CAM tree. You can also click the Geometry item to highlight the selected geometry in the graphics area.

 

Notice that the Hole and Counterbore Diameter and Depth were automatically set from selecting the cylindrical faces of the holes.

 

6. Click Next>> to go to the Feature settings.

Part 4) Define the Feature Parameters

1. The feature parameters such as the Rapid Plane and Feed Plane can be adjusted here.
   
   

2. You can use the Pick Top and Pick Bottom buttons to select geometry to set the Feature Depth and Top of Feature when needed, but no changes are needed for this example.
   
   

3. Through Hole is selected because the Drill hole goes through the part.

 

Click Next>> to go to the Machining Strategy.

Part 5) Define the Machining Strategy

1. With the Default Strategy, Counterbore Hole, selected, notice the Current Operations list.
   
   The default Operation Template contains three operations: Center Drill, Drill, and Counterbore Drill.
   
   

2. To add a chamfer operation, first click to select the Counterbore Drill operation in the Current Operations list.
   
   

3. In the Available Operations list, select Chamfer Drill, and click (Add Operation).

    

Note: When you add an operation from the Available Operations to the Current Operations, it is added below the currently selected operation.

 

Click Next>> twice to go to the Postingsettings.

Part 6) Define the Posting Parameters

1. Confirm that the proper Work Offset Number is selected for the feature.

 

Click Next>> to go to the Center Drill tool settings.

Part 7) Define the Tool  and Operation Parameters

1. Notice that the System Tool check box is selected.
   
   When using System Tool, the software searches the Tool Crib for a matching tool to set the Center Drill parameters.
   
   If the tools in the Tool Crib have a tool holder assigned in the Tool Library, it is automatically assigned in the wizard.
   
   You can clear the System Tool check box to modify the tool parameters.
   
   

2. For this example we use the default tool holder assignments that are installed with the software.
   
   

3. You can set the Tool Number, Offset Registers, and Feeds and Speeds manually by clearing the check box and typing the values, or you can use the automatically assigned values.
   
   

4. Click Next>> to go to Parameters.
   
   

5. In the Depth box, update the value to 0.065.
   
   

6. Repeat this process for the remaining operations making any necessary changes.
   
   For this example, the Use Cutting Conditions check box is selected for each operation to automatically calculate the parameters using the Cutting Conditions for the job.
   
   

7. After defining all of the operation parameters, click Compute to create the toolpath.

 

 

Editing a Feature

After finishing the wizard, you can right-click Feature Mill Counterbore Hole and click Editto modify the feature.

Part 8) Simulate the Program

1. To view the program simulation, right-click Milling Job and click Simulation.
   
   For help with using simulation, view Getting Started With Simulation.
   
   

2. To finish the simulation, in the BobCAM menu, click Exit Simulation.

Part 9) Post the NC Program

1. In the CAM tree, right-click Milling Job, and click Post.

 

The NC program displays in the Posting Manager.

 

You can right-click anywhere in the Posting Manager to access Save As or NC Editor.

Related Topics

Milling Features Overview