Ramp Rough Turning Operations

Tooling for Ramp Rough Turning

The following tooling may be used:

• External and Internal insert-holders with round inserts.

Note that the following attributes may influence machining (they are located on the Insert-holder's Technology tab):

• Trailing angle
• Leading angle
• Max Recessing Depth
• Max Boring Depth.

These attributes take tooling accessibility into account and may reduce the machined area.
However, you can use the Insert-Holder Constraints option on the operation editor to either ignore or apply these tooling attributes. You can replay the operation to verify the influence of these attributes on the generated tool path.

Note that the Insert-Holder Constraints setting does not influence the Entry Flank Angle defined in the operation editor.

Geometry for Ramp Rough Turning

Part and Stock profiles are required. They can be specified as follows:

• select edges either directly or after selecting the By Curve contextual command. In this case the Edge Selection toolbar appears to help you specify the guiding contour.
• select the Sectioning contextual command. Please refer to Sectioning for details of how to use this capability.
  Please note that the sectioning selection method is not associative.

The End Limit option allows you to specify a point, line, curve or face to relimit or extrapolate the selected part profile. If a face is specified, the end element is the intersection of the face and the working plane. The position of the end of machining is defined with respect to this element by one of the following settings: None / In / On / Out.

The Stock Extension distance

allows you to extend the stock in the machining direction and, to any desired length. This can be useful in Rough turning scenarios, where you want to machine beyond the stock profile. This extension is taken into account for toolpath computation when an End limit element is defined and used on the operation (when End limit mode is different from None).

The extension distance defines the extended domain for toolpath computation. Note that the end limit is respected only when it is specified (according to the In / On / Out mode) inside the extended domain.

The figures below show that an End limit is defined (selected and mode different from None) and a Stock Extension distance is defined (greater than 0).

The tool moves beyond the stock (extension distance). This distance defines the machining domain extension for toolpath computation.

Note that in this particular case, the limit is not reached (In / On / Out) because it is outside the extended machining domain.

Relimiting the area to machine by means of limit elements

If you specify a point, it is projected onto the part profile.
A line through the projected point parallel to the radial axis delimits the area to machine.

If you specify a line, its intersection with the part profile is calculated (if necessary, the line is extrapolated).
A line through the intersection point parallel to the radial axis delimits the area to machine.

If you specify a curve, its intersection with the part profile is calculated (if necessary, the curve is extrapolated using the tangent at the curve extremity).
A line through the intersection point parallel to the radial axis delimits the area to machine.

Orientation for Ramp Rough Turning

The following Orientations are proposed: Internal, External and Frontal (for Face Roughing only).

The selected Orientation defines the type of geometric relimitation to be done between the stock and part geometry in order to determine the area to machine. Selected part and stock profiles do not need to be joined (see the following figures).

External Ramp Rough Turning

Internal Ramp Rough Turning

Frontal Ramp Rough Turning

Frontal machining is proposed for face Ramp Rough Turning. In that case, the minimum and maximum diameters of the area to machine are determined by the stock profile dimensions.

For example, in the following figure the area to machine is relimited by the spindle axis because the stock profile is also relimited by the spindle axis.

Part and Stock Offsets for Ramp Rough Turning

• Stock offset: specifies a virtual displacement of the stock profile.
• Part offset: specifies a virtual displacement of the part profile.

  

• Axial part offset: specifies a virtual displacement of the part profile along the spindle axis direction.

  

• Radial part offset: specifies a virtual displacement of the part profile in the radial axis direction.

  

• End limit offset: distance with respect to the end element (only if end element is a line or a curve, and when In or Out  is set for end element positioning).

Offsets can be positive or negative with any absolute value. The global offset applied to the part profile is the resulting value of the normal, axial and radial offsets.

Location and Limits for Ramp Rough Turning

The following machining Locations are proposed:

• Front, the part is machined toward the head stock
• Back, the part is machined from the head stock.

Orientation and Location settings determine the way the program closes the area to machine.  The following options allow you to restrict the area to machine that is pre-defined by the stock and part. You may want to restrict this area due to the physical characteristics of the tool and the type of machining to be done.

Minimum Machining Radius

Maximum Machining Radius (for internal machining)

Note that Max Boring Depth is defined on the tool.

Axial Limit for Chuck Jaws (for external or frontal machining): Offset defined from the machining axis system.

Machining Strategy Parameters for Ramp Rough Turning

Path Definition for Ramp Rough Turning

• Machining tolerance
• Max Depth of Cut
  This option is used to specify the maximum distance between passes.
• Under Spindle Axis Machining
  For Face Ramp Rough Turning, this option allows you to request machining under the spindle axis.
• Machining Direction (only for Face Roughing with Frontal machining)
  You can specify the machining direction with respect to the spindle axis by means of the To/From Spindle Axis choice.
• Entry Flank Angle
  The insert geometry is taken into account to avoid collision by reducing the maximum slope on which machining can be done. Defining a Entry Flank Angle on the operation allows you to further reduce the area to machine.
  
  Note that a leading angle can also be defined on the insert-holder to define the maximum slope on which machining can be done. In this case and if the Insert-Holder Constraints setting is applied (see above), the angle that reduces the slope the most will be taken into account.
• Start pass mode is defined by one of the following settings:  Chamfer, Rounded, None.
• If Rework mode is set, the following options are available:
  • Distance before Rework Plunge
  • Angle before Rework Plunge.

Lead-in and Lift-off for Ramp Rough Turning

These options allow penetration into the workpiece at a reduced feedrate in order to prevent tool damage.

• Lead-in Distance
  Defined with respect to the cutting direction. It takes the stock profile and stock clearance into account. The tool is in RAPID mode before this distance.

• Lift-off Distance and Lift-off Angle
  These parameters define the lift-off vector at the end of each pass with respect to the cutting direction.

Feeds and Speeds for Ramp Rough Turning

Speed unit can be set to:

• Angular: spindle speed in revolutions per minute
• Linear: constant cutting speed in units per minute

then you can give a Machining Speed value.

The following feedrates can be set to either Angular units (length per revolution) or Linear units (length per minute):

• Machining
• Lead-in
• Lift-off
• Plunge
• Light loading
• Air cutting.

Feedrates in units per minute are also available for air cutting (for example, during macro motions and path transitions).
Note that RAPID feedrate can be replaced by Air Cutting feedrate in tool trajectories (except in macros) by selecting the checkbox in the Feed and Speeds tab page .

Dwell setting indicates whether the tool dwell at the end of each path is to be set in seconds or a number of spindle revolutions.

Please note that decimal values can be used for the number of revolutions. For example, when machining big parts that have a large volume, it can be useful to specify a dwell using a value of less than one revolution (0.25, for example).

Tool Compensation for Ramp Rough Turning 

You can select a tool compensation number corresponding to the desired tool output point. Note that the usable compensation numbers are defined on the tool assembly linked to the machining operation. If you do not select a tool compensation number, the output point corresponding to type P9 will be used by default.

Approach, Retract and Linking Macros for Ramp Rough Turning

The following Approach and Retract macro modes are proposed: Direct, Axial-radial, Radial-axial, and Build by user. The selected macro type (Approach or Retract) defines the tool motion before or after machining.

Various feedrates are available for the approach and retract motions (RAPID, lead-in, lift-off, and so on). Local feedrates can be set to either Angular units (length per revolution) or Linear units (length per minute).

Linking macros, which comprise retract and approach motion can also be used on Ramp Rough Turning operations.
Approach and retract motions of Linking macros are interruptible. It can be useful to interrupt an operation when the foreseeable lifetime of the insert is not long enough to complete the machining.

See Define Macros on a Turning Operation for more information.