VERO UK TRAINING MATERIAL

Version 20

Cutting a 4 axis part

Cutting a 4 axis part

Things that will be covered in this section.

• Defining stock and the piece

• Using feature recognition to cut apertures in solid model

• Applying no core operation

• Use dynamic section to create 4 axis profiles

From the menu select file > Open

Navigate to the following location and open the file - 4ax_featrec.wkf

The file contains two solid bodies; the stock material and the part to machine. Within the cam navigator we need to define which solid is which in order to use for kinematic simulation later in this section.

Open the CAM navigator; Select Machining > CAM Navigator,

Define the stock model in the model manager; right hand click on the model manager branch and select add model

The Type can be changed to Stock from the drop down menu, the Ok button is then clicked and the model selected.

Select the outer most solid (highlighted below):

The piece manager stays active in order to select other geometry for the stock; this is not required for this example, so close the piece manager with the X.

In the model manager, the stock is now defined. In order to aid selection, the stock model can be hidden by clicking the tick next to the stock model.

The part to be cut can now be seen on the screen:

The piece can now be defined; select the add model option as before but now select the type to be Piece, OK the dialog as before and then select the remaining model from the screen:

The model for the piece and stock are now defined in the model manager.

There are several operations to perform in order to create the part. Before this can be done we need to create the features to be cut.

Using Feature recognition to create machinable features

Right hand click on the model manager and select; Run Recognition:

Tip! - pressing the “R” key on the keyboard also runs the recognition.

The system will now process the entire model and detect features; this may take a little time. The progress is shown in the process manager window that is displayed:

The system should recognise several features and add these to the model manager. Selecting each feature in the list highlights the feature on the screen.

The recognition will find the outer tapered profile and the four 2mm holes. However the tapered internal feature has not been detected and will therefore need to be defined manually.

Extracting profiles from a solid body

The internal aperture can be defined as a feature manually. As the aperture is a 4 axis cut, the feature will need to de defined using two profiles.

The upper profile can be created quickly using the profile from face.

Select the profile from face command; Wireframe > profile > profile from face

Select the top face of the model;

Retain the inner loops should be set, as this is the profile that we require.

OK the dialog and several profiles will be created.

Use the delete command to delete the outer profile and hole profiles that are not required.

NOTE:- This is easier if the filter is set to select profiles only

Rotating the model so that you can see the underside of the part, shows that the lower profile cannot be created from a face. It is also not possible to create a profile at Z0. Therefore the quickest way would be to slice the part in the XY plane and create a profile at a Z height where creating a section would produce a closed profile.

Using the dynamic section command to create the lower profile

Open the dynamic section command: Analysis menu > dynamic section dialog

The dynamic section dialog creates section in X, Y, Z or in a customise plane. Select the Z axis and move the slider so that you can see the highlighted position:

Select the select section plane button;
and select the following point:

The section plane will relocate to that the select position and the lower profile geometry will be seen:

Use the create section command button to create the geometry at the section plane;
the body will need to be selected.

The profile is then generated.

The upper and lower profile can now be used to create a 4 axis feature.

In order to see the newly created geometry, the piece can be hidden by unticking the box next to the piece entry in the model manager.

The dynamic section command has produced some additional unwanted geometry that can be removed using the delete function:

The lower geometry was created as segment lines and arcs using the dynamic section; therefore it needs to be converted into a profile.

The closed profile command is used to create a profile from the line\segments or arcs; select wireframe > profiles > closed profile or the
button.

Select the first line:

And then use the automatic button;
to “close” the profile.

Confirm the profile creation; selecting yes.

In order to cut the 4 axis aperture, a feature needs to be created from the two profiles

Add a 4 axis feature using the command from the right hand click menu in the model manager:

Select the lower profile:

And then select the upper profile:

The properties of the feature can be defined:

Note! - The feature is defined as a pocket and the height has already been set; do not change this. Select OK to create the feature.

The model manager now shows the new feature as a 4 axis pocket.

Selecting it in the list will show the rendered image of the feature. This will show that the feature in this case is twisted.

The reason for the twisted feature is that the start positions for the upper and lower profiles are at completely different locations.

This needs to be modified so that the feature is cut correctly.

The start positions are edited by double clicking the feature in the model manager. The properties of the features are shown:

Then select the add\ edit constraints button,

Then use the Change profile start point button.

The lower profile can be edited by selecting it and then defining the start point; a position half way along the line segment can be picked:

Use the same method to define the start point for the upper profile; this should b defined at the following position:

Close the features properties dialogs

All the features are now ready to be machined.

Machining the hole features

A no core (pocketing) operation is to be added to the hole features. Select the add operation command from the right hand click menu on the feature:

Tip! The 4 hole features are the same size and therefore they are grouped together under one branch. The operation can be added to all the holes by selecting add operation with this branch selected.

The operation dialog is shown; select the wire erosion operations and then the 2 axis operation.

Note!

- Only the 2 axis operation is available as the holes are only 2 axis features.

- If you have not set a default machine, you will be asked to choose one before continuing to the next stage.

When the first operation is added the project settings must be set:

Select the piece material.

The reference piece and stock are already defined. The wire type can also be set.

OK the dialog and the operation is created. It is shown and edited from the wire tab of the CAM navigator.

Double click the Wire operation to edit the parameters of the operation.

To change the operation to a pocketing operation, activate the no core option. The stepover distance and type of pocket mode for round holes can be set:

Tip! The spiral pocketing mode may give you better finish as it will not leave marks where the wire moves out.

Select three cuts; be aware the first cut only is the pocketing operation. Subsequent cuts are profiling passes to finish the aperture. Therefore an offset must be applied to the first pocketing operation.

Machining the outer profile and the manually defined 4 axis feature

Now add another 4 axis operation to cut the outer profile and the manually defined outer feature

The start hole positions may also require changing.

Note! The programming planes are taken from the feature but these can be modified to be the same as the previous operations;

Running Kinematic simulation

Once all operations have been added the kinematic simulation can be used to fully simulate all operations and show material removal.

To run simulation, select the Kinematic simulation icon from the right hand click menu;

Now the simulation screen will appear:

There are many options on the kinematic simulation; these will be shown to you by your instructor.

Additional Examples - try it out!

Open the file brov.wkf

Use feature recognition to find features

Add operations to the part

Run kinematic simulation

Open the file wire4.wkf

This part shows that although the upper and lower surfaces are complex the recognition will find the wire-able feature

Open the file 4AX_SOLID.X_T

Open the file RAIL.wkf

Define the work holding as obstacles

Add operations to the features created on this part.

Open the file vane.X_T

Try to use feature recognition; if this is not successful try to use the dynamic sectioning dialog.

Open the file insert.X_T

This one also may require sectioning before trying to create operations.

VERO UK

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