Tutorials:-Working with Power MILL " PART II" Machining Setup

Sourbh

10 Aug, 2013 02:31 AM

Here is the Next Part of Working with Power Mill..

Follow the Steps and You will found your way with Power Mill.

Some text are Referenced from Book and Online Training Tutorials

Thanks and Enjoy..!!

1. Step 1:

   **Setting up direct access to regularly used files**

   To Import a Model the user can select File > Import Model from the top pulldown menu. A selection of sample model files are supplied and installed with PowerMILL in a default directory called Examples. These are directly accessed via the icon in the Import Model form.

   Alternatively, regularly used models can be accessed quickly with the user definable buttons and on the Import Model form.

   •From the Main pulldown menus select Tools - Customise Paths.

   •Select the option File Dialog Button 1 followed by the Add path to top of list icon and browse to:-
   D:\users\training\PowerMILL_Data\Models.

   •Repeat the last process, but this time set File Dialog Button 2 to provide direct access to:- D:\users\training \PowerMILL_Data.

   Note:- Outside the training environment the location of the PowerMILL_Data directory will depend on where the user has installed it!

   

2. Step 2:

   **Loading a Model into PowerMILL**

   •From the Main pulldown menus select File - Import Model.
   •Use Shortcut Button 1 or browse to d:\users\training\PowerMILL_Data\Models

   Note: A variety of different types of Model format can be Imported into PowerMILL. These can easily be discriminated on the form using the filter Files of type to widen or narrow the choice for file extension.

   •Click on the file name speaker_core.dgk and then select the Open.
   •Select View from top (Z) followed by Resize to fit from the Viewing toolbar to the right of the graphics area.

   The model will be displayed (as shown) in the PowerMILL graphics area looking down the Z-axis with X aligned from left to right and Y from bottom to top.
   In most cases the X dimension of a machine tool table will be greater than Y in which case the longer side of the component may be in excess of the travel limits in Y.
   If this is the case it will be necessary to align the component with the longest side along X to ensure that it can be positioned within the travel limits.

   

3. Step 3:

   **Viewing the Model* *

   Although the model is displayed it is a good idea to look at it from all angles to fully understand its size and features.

   •Select an isometric ISO 1 view.
   Although it is possible to rotate the actual component this is not generally regarded as the ideal approach.
   An additional moveable datum (Workplane) will be created and rotated through 90 Degrees to effectively create the condition that the longer side of the component is parallel with the front of the machine.
   The original coordinate set-up can then easily be re-activated for tasks such as checking dimensions.

   

4. Step 4:

   **Orienting the Model – creating the machining datum using a Workplane**

   A Workplane will be created and rotated through 90 degrees about Z to effectively arrange the longest lower front edge of the model to be aligned to the front of the machine tool i.e. along the X-axis.

   •Right click over Workplanes in the PowerMILL explorer and select Create Workplane.
   Workplanes are alternative or additional component datums that can be moved and/or orientated within the global environment. They are frequently used in 3 Axis machining and are an essential item in the application of 3plus2 and 5-Axis machining strategies.

   The Workplane creation and editing form will appear.
   For easy identification it is recommended to appropriately rename any entity created in the Explorer.
   •In the form modify the default Name to Datum.
   •Set the Active Workplane to Datum.
   The next step will be to rotate the new Active Workplane to indirectly re-orientate the model.
   •Enter Angle 90.0 before selecting the Rotate - Around Z icon.
   •Accept the form
   •Select a View from top (Z) and observe the effect of the rotated, Active Workplane providing a more suitable machining position for the model.

   It will not always be necessary to create and rotate or move a Workplane after import into PowerMILL. It depends on the original, orientation of the model when exported from the CAD software.

   

5. Step 5:

   **Examination of Model Properties**

   Information regarding the model dimensions in relation to the world datum (Transform) or (if present), an Active Workplane can be obtained.

   •In the explorer Right click over Models and select Properties.
   The values in this form can be copied (Ctrl C) and then pasted (Ctrl V) into other forms.
   The Workplane is moved up in the Z plane so that it is situated at the maximum height of the model.
   The form shows that the current maximum Z value is 115.47048mm. It will be necessary to move the Workplane by 115.47048 to position it at the maximum height of the model.
   Highlight the Maximum Z value (115.47048) by swiping over it with the left mouse button and press Ctrl C on the keyboard to Copy the value to the buffer.
   •Eject the Model Properties form by clicking X in the top right corner.
   •In the explorer Right Click over the Workplane named (Datum) to access the local pull down menu.
   •Select Edit - Workplane to open the form (above right) and use Crtl V to replace the previously stored value (115.47048) into the Distance box before selecting the Relative Position - Along Z icon.
   •Accept the form.
   •Select a Y- view.
   The Workplane is now in position on the top of the model.
   

   

6. Step 6:

   **Minimum Radius and Draft Angle shading views**

   Visual checks can be made quickly with the use of two shading options found in the views menu on the right hand side of the screen.
   It is useful to know before generating tools and toolpaths what the minimum radius is on the model and also whether there are any undercuts or draft angles
   •Open the Shading Toolbar by clicking the small arrow as shown above.
   •Select the Minimum Radius Shade icon on the toolbar.
   Any internal radii that are smaller than the specified Minimum Tool Radius will be shaded RED. The settings are located in the explorer - Model pull down menu in Drawing Options.
   Examine the model to identify areas that are inaccessible to the specified radius (shaded Red)
   The two internal radii can be seen shaded red visually identifying that they will not be machined to their correct size if the default value tool was used.
   The specified Minimum Tool Radius can be modified to suit in the Drawing Options area within the Models menu in the explorer.

   •In the explorer Right click over Models and select Drawing Options
   •Change the Minimum Tool Radius value to 5.
   The shading on some parts of the model has changed from Red to Green signifying that from a finishing viewpoint these local areas are fully accessible to a Dia 10 Ball Nose cutter.
   •Change the Minimum Tool Radius value to 2.
   All of the red areas have now disappeared which suggests that the maximum tool size guaranteed to access all areas of the component would be a Dia 4 Ball Nose cutter.
   The model can also be visually inspected for the size of draft angles and undercuts.
   •Select the Draft Angle Shade icon on the shading toolbar.

   The model is shaded in three different colours, red, green and yellow.
   The red areas represent angles equal to or less than the current Draft Angle specified in the Drawing Options form (default is 0).
   The green areas represent angles above the current Warning Angle specified in the Drawing Options form (default is 5).
   The yellow areas represent the areas between the current Draft Angle and Warning Angle.
   On this particular model the yellow areas represent angles between 0 and 5 degrees.
   • To check for undercuts change the Draft Angle to –0.2 and the Warning Angle to 0.2.
   All of the red areas have disappeared and all that remain are green and yellow. If any red areas remain then these would indicate an undercut situation greater than –0.2 degrees.
   The yellow areas indicate on or near vertical faces because the difference between the Draft and Warning Angles is so small.
   •Accept the Drawing Options form
   •Select the Draft Angle Shade icon again to turn off the shading.
   •Make sure the Wireframe icon from the View toolbar is on so the model is displayed in Wireframe only.

7. Step 7:

   **Measuring the model**

   The user may require dimensional information relating to certain features on the model. A measuring tool is provided in PowerMILL that allows the user to snap in the graphics area to obtain dimensions based on points lines and arcs.
   Before any such measurements can be taken the PowerMILL, Snap Filter will need to be modified.
   •From the top Pull Down menus select Tools > Snap Filter and use the left mouse key to untick - Anywhere
   If Anywhere is unticked then measurements can be only be snapped onto the remaining ticked entities and not in free space
   •Zoom into the area shown by the arrow below
   The gap at the bottom of the slot will be measured to determine its size and depth.
   •From the Main toolbar select the Measure model icon.
   The Model Measurement for appears defaulted to Line. An Anchor Point is required to commence measuring.

   •The PowerMILL Calculator form will open in Line measurement mode. Using the left mouse button drag a window around (or snap) point 1 shown below to display the XYZ coordinates in the form.
   Drag a window around (or snap) point 1.

   The Anchor Point is now selected and is represented by a small circle.
   The x, y and z values seen in the above form are relative to the Active Workplane ‘Datum’.
   •Drag a window around (or snap) point 2 to obtain the final ‘point to point’ measurement information.

   A temporary line appears connecting the two points, and the information relating to the line is displayed in the form.
   Minimum Radius is measured via the Circle tab combined with snapping three points on the model.
   •Select the Circle tab on the Model Measurement form and zoom into the area shown below.
   •Select three points along the arc either by dragging a small window around, or snapping onto each one as shown below
   A temporary circle will appear after the third point is selected as shown
   The Circle measurement form will display details of the arc as shown.
   •Close the Model Measurement form.
   

   

8. Step 8:

   **PowerMILL Panes**

   On the left hand side of the screen above the explorer are the PowerMILL panes.

   The standard format pane is denoted by the PowerMILL symbol and contains the explorer tree categorised into NC Programs,Toolpaths, Tools, Boundaries, Patterns, Feature Sets, Workplanes, etc.

   The second pane is the HTML browser used for viewing HTML files or Help files and the third pane opens the PowerMILL Recycle Bin.

   

9. Step 9:

   **Setting Feed rates**

   Feedrates can be set individually for the current tool and toolpath or loaded from a database of predefined values. At this stage we will look at setting the feedrate individually.
   The Tool Database will be covered later in the course.
   •Click the Feeds and Speeds icon on the top toolbar to raise the Feeds and Speeds form.
   In the Cutting Conditions section of the form, enter a Spindle Speed of 1200 and a Cutting Feed Rate of 400 (as shown above).
   •Accept the form.
   •Save Project As - D:\users\training\PowerMILL-Projects\Spkr-Core (but do not close).

   

10. Step 10:

    **Tool and Holder Definition**

    •Open the Tip Radiused tool form.
    •In the (above) default Tip form define a Dia 50 Tiprad 6 - Length 125 - Named D50T6 - Tool Number 6.
    •In the Shank form, click the Add a shank component icon and enter Upper/Lower Diameter 50 and Length 125.
    The Overhang is the vertical distance from the bottom of the holder to the tip of the cutter.
    • In the Holder form, click the Add holder component icon entering Upper Diameter 120 - Lower Diameter 80 - Length 125 and Overhang 250.
    •In the Holder form, click the Add holder component icon entering an Upper/Lower Diameter 120 and Length 100.
    •Close the form
    The way in which the tool is displayed can be controlled by right clicking on TOOLS in the tree browser pane and selecting Shaded.

    

11. Step 11:

    **Material Block Definition**

    •Calculate a 3D working volume (Block) to actual model dimensions using the Defined by - Box option
    The default option for Block is Box (A rectangular volume). Other options include Cylinder (a Cylindrical volume), a Triangle model (Casting) available in PowerMILL PRO only, and Picture/Boundary (Extruded 2D wireframe contours).
    The dimensions of the Block can be entered manually or calculated directly to the Type of entity:-
    Model, Boundary, Pattern, or Feature.
    The Opacity slider controls the degree of shading (clear to dense).
    

    

12. Step 12:

    **Rapid Move Heights**

    •In the Rapid Move Heights form click the Reset to Safe Heights tab and ensure that in the Incremental Heights area that Rapid Move Heights uses the Skim option.
    The Skim option enables safe rapid moves between tool tracks within the Block volume.

    

13. Step 13:

    **Start and End Point **

    •In the Start and End Point form use the default settings :-
    Start Point - Block Centre Safe and End Point - Last Point Safe.

    • Select Save Project to update the saved PowerMILL Project (Do not close the Project).
    Note: The Project is stored in:-
    D:\users\training\PowerMILL-Projects\Spkr-Core