Apostila PowerMILL 5.5 - 5 Eixos

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PowerMILL 5.5 - Five Axis

Course

Delcam plc, Talbot Way,

Small Heath Business Park, Birmingham, B10 0HJ.

www.delcam.com

Training Centre Customer Support

Tel: 0121 683 1050 Tel: 0121 683 1010

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Important Notice

This document is supplied as part of a Delcam Training Course. It is not intended to be distance learning material: rather as an aid for Tutors when presenting material to course delegates and as a subsequent aid memoir to those delegates.

Delcam does not accept responsibility for any personal belongings / valuables whilst on the premises. Delegates are advised to keep their belongings on their person at all times.

Delcam plc. has no control over the use of the software described in this document and cannot accept any responsibility for any loss or damage howsoever caused as a result of using the software. Users are advised that all results from the software are checked by a competent person in accordance with good quality control procedures.

The software described in this document is furnished under a license agreement and may be used only in accordance with the terms of such license.

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PowerMILL5.5 - Five Axis Contents

Chapters

Page Number

1. 3+2 Axis Machining and Drilling 1 - 22 2. Five Axis Tool Alignments 23 - 42 3. Surface Projection Finishing 43 - 52 4. Five Axis Pattern Finishing 53 - 68 5. Five Axis Profile Finishing 69 – 74 6. Five Axis Embedded Pattern Finishing 75 - 78 7. Swarf Finishing 79 - 86 8. Rotary (4th Axis) Machining 87 - 92 9. Positional Tool Movements 93 - 94 10.Tool Axis Limits 95 - 110 11.Toolpath Simulation 111 -116 12.Appendix 117 -122

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1. 3 + 2 Axis Machining

Introduction

On a 3 + 2 Axis Machine it is possible to index the head and/or bed to realign the tool prior to performing standard X Y Z transitions. This is achieved either by manual adjustment or as part of the cnc control.

It is possible for customers who do not possess a PowerMILL Multi-Axis licence to create 3+2 strategies by using individual Workplanes to control Tool Alignment and output ncdata via the NC Preferences form with the Automatic Tool Alignment set to Off.

It is however both faster and easier to create 3 + 2 toolpaths if the Multi-Axis licence is available as it provides access to a larger range of options with minimal dependency on individual Workplanes. Either way PowerMILL enables components normally requiring a series of separate 3-Axis operations to be machined in one set-up. This could include direct machining of undercut features or sidewalls deeper than the maximum tool length.

It is essential to apply suitable Toolpath - Leads, Links, and Extensions to eliminate any potential gouges.

3 + 2 Axis - Machining Example

• Delete all entities and Import the 3plus2b.dgk model from the directory

five_axis/3plus2_as_5axis.

• Select an Isometric view and consider the machining options. Note the relatively

high sides of the component and the orientation of the three recesses making it impossible to machine aligned to the Z-Axis alone.

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• Create another Workplane and move it by a distance of Z175 to clear the top of the component and Rename it as ztop175_A.

• Activate the Workplane - DATUM.

Note: Workplane alignment for compound angles is easier to achieve using PowerSHAPE (If familiar with the commands). A limited functionality version called the PS-Sketcher is accessible as standard from PowerMILL. Create a simple, two point Pattern to enable access to the PS Sketcher, Select the model and Insert - PS Sketcher. Create, reposition, and re-orientate Workplanes dynamically as required. Otherwise use the long method from within PowerMILL as described below.

• Create a new Workplane and Rename it as x0el30_B (This will be activated). • Using the Model Measurement tool , snap or box the wireframe defining the

centre of the recess base positioned along the X-Axis. The form will display the

current coordinates at this point (shown below left). Do not close the form as data is to be individually copied and pasted into the Workplane - Edit – Move By

options.

• Reposition the Workplane centrally at the bottom of the recess using values

copied from the Measuring tool form via the PowerMILL Calculator (X move

data shown above right).

• Move the Workplane along X by Pasting the value into the Box (above right) opened by clicking X0el30_B - Edit -Move By and then repeat the whole

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• Use the Model Measurement tool to select the bottom and top coordinates of the line running up the pocket (Defined from O to X below). This will provide angular

data to enable a Workplane - Rotation about the Y-Axis (XZ Angle) such that the Z-Axis is normal to the pocket (add a negative sign if necessary).

• Then align it about the Z-Axis (normal to the base of the recess) ensuring that the

X-Axis is pointing in the anticlockwise direction as viewed from the top of the

component (If not already the case).

• Create another Workplane for the 2nd recess and rename it as x120el30_C. • Activate the Workplane - DATUM then Select and Rotate the Workplane -

x120el30_C around the Z-Axis by 120 degrees

• Repeat for the 3rd recess, rotating a copy of the Workplane a further 120 degrees and renaming it as x240el30_D.

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• The component is now ready to be machined creating separate strategies relative to the 4 different tool alignments A, B, C, and D. (Workplanes ztop175_A,

x0el30_B, x120el30_C, and x240el30_D relate to tool alignments A, B, C, and D

respectively).

It is advised that the Rapid Move Heights and Start Point for each toolpath be above the top of the component to allow for safe movement between individual machining Workplanes (as shown left).

• The Settings for Rapid Move Heights and Start Point as appliedto the local recesses are as shown above and as entered into the forms below.

Once all Workplanes have been created a series of toolpaths can be created switching from one Workplane to the next to provide suitable Tool Alignments. Each individual toolpath is effectively a 3-Axis operation relative to the currently active Workplane.

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Suggested Roughing/Semi-Finishing Strategy

TOOL WORKPLANE STRATEGY STOCK TOOLPATH 3-Axis ROUGHING

DIA 40 End Mill ztop175_A OFFSET 1.0mm em40a1 Stepover 35 - Stepdown 10

3+2 ROUGH RECESSES

DIA 10 Slot Drill x0el30_B OFFSET 0.5mm sd10b1 DIA 10 Slot Drill x120el30_C OFFSET 0.5mm sd10c1

DIA 10 Slot Drill x240el30_D OFFSET 0.5mm sd10d1 Stepover 5 - Stepdown

3+2 SEMIFINISH RECESSES

DIA 6 Ball Nose x0el30_B OPTIMISED CONST Z 0.5mm bn6b1

DIA 6 Ball Nose x120el30_C OPTIMISED CONST Z 0.5mm bn6c1 DIA 6 Ball Nose x240el30_D OPTIMISED CONST Z 0.5mm bn6d1 Stepdown 1

After the creation of toolpaths for 3 + 2 Axis valid ncdata can only be output using a compatible post-processor. For programs containing multi-alignment toolpaths the NC Programs output options create the ncdata from a common, initially activated datum (In this case the Workplane - ztop175_A). This option is selected in the NC Preferences form.

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3+2 Axis – Stock Model Application

The Stock Model represents the un-machined stock at any point in the machining process. It is applied by first creating a Stock Model entity by applying a Block, followed by various toolpaths. After each update, the stock model adjusts itself to show the un-machined material remaining on the block.

• Delete all and Reset forms.

• Import the model Lower_Die.dgk from the local directory

PowerMILL_Data\five_axis\PressTools

The model contains an undercut region that would be difficult to machine using the normal 3-axis roughing and finishing strategies. By using the 3+2 option, with an individual

Workplane controlling tool alignment, the undercut can be roughed and finished with standard toolpaths.

• Open the Block form and Calculate to Min/Max limits.

• Select the icon to Lock the block to the global co-ordinate system. • Accept the form.

By locking to the global co-ordinate system the blocks orientation and position remain unchanged when activating alternative workplanes.

• Create a 16 ball nosed tool and Rename 16bn. • Create a 6 ball nosed tool and Rename 6bn. • Activate the work plane Machine_Top

• Reset Safe heights with Rapid Move Type set to Skim. • Reset Start Point as Automatic Block Centre Safe Z. • Activate the tool 16bn.

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• Select the Toolpath Strategies icon and from the 3d Area Clearance tab the Raster Area Clearance option and enter the values exactly as shown below.

• Rename Top_Ruf.

• Angle 0.0 • Apply and Accept the form.

• Activate the tool 6bn.

• Select the Toolpath Strategies icon and from the Finishing tab the Raster Finishing option and enter the values exactly as shown below.

• Rename Top_Fin • Angle 90.0

• Start Corner Upper Left. • Style One Way.

• Lead/Links

Lead in :Vertical Arc Angle 90 Radius 3 Lead out :None.

Links : Short On Surface Long/Safe Skim

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The top surfaces of the model have been roughed and finished to size. Toolpaths shown in the following illustration ( Lead/Links undrawn.)

• Animate each toolpath in turn to observe the results.

• In the PowerMILL explorer right mouse click Stock Models to open the local menu and select Create.

A stock model has been created in the explorer window but will remain empty until items are added to it.

• Right Click over the toolpath Top_Ruf in the explorer window and select the option Add to Stock Model.

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• Right Click over the toolpath Top_Fin in the explorer window and select the option Add to Stock Model.

Both toolpaths have been added to the Stock Model but the Stock Model itself has yet to be calculated.

• Right Click over the Stock Model in the explorer window and select the option

to Calculate.

• Select a View from Right (X)

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• Activate the work plane Machine_Side. • Select a View from Right (X)

The Machine_Side workplane enables vertical tool alignment for the undercut region to be machined.

• Reset Safe heights with Rapid Move Type set to Skim and Start Point

as Automatic Block Centre Safe Z.

• Select the Toolpath Strategies icon and from the 3d Area Clearance tab the Raster Area Clearance option and enter the values exactly as shown below.

• Rename Side_ruf

• Select Rest Machining and use Stock

Model 1.

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Selecting the Rest Machining option ensures that all cutting is contained within the Stock Model, therefore avoiding any unnecessary moves into areas that have been previously machined.

• Right Click over the toolpath Side_ruf in the explorer window and select the option Add to Stock Model.

The toolpath has been added to the Stock Model, which will need to be re-calculated. • Right Click over the Stock Model in the explorer window and select the option

to Calculate.

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A boundary can be created around the stock model rest material that identifies the difference between the Stock Model and the actual model. This boundary can then be used to finish the component in the Rest areas only without the cutting tool encroaching into regions that have already been machined.

• Right Click over Boundaries in the explorer window and select Create

Boundary - Stock Model Rest.

The Stock Model Rest dialog is displayed.

• Select Stock Model 1 and Expand Area By 1.0 • Set Tolerance 0.02

• Select the tool 6bn.

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The Boundary has been created around the remaining stock material on the component.

• Select the Toolpath Strategies icon and from the Finishing tab the Raster Finishing option and enter the values exactly as shown below.

• Rename Side_fin.

• Start Corner Lower Right.

• One Way set. • Select Boundary 1 • Lead/Links

Lead in :Vertical Arc Angle 90 Radius 3

Lead out :None.

Links : Short On Surface Long/Safe Skim

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The toolpath is shown limited to the boundary (Lead/Links Undrawn)

• Add the toolpath Side_fin to the Stock Model and re-calculate. • Activate the work plane Machine_Top

• Select View ISO 3.

• Right click over NC Programs in the explorer window and select Create NC

Program.

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• Close the NC Program dialog box.

• Raise the Viewmill toolbar and Toggle the viewmill window. • Set the Icon to View Complete NC Program.

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3+2 Axis - Drilling Example (For users with MultiAxis licence) The PowerMILL - Drilling options operate on Hole Features and not directly on the Model. This enables drilling to take place without the need to modify or trim back the existing surface data.

• Delete all entities and Import the model drill5ax_ex1 from the directory

five_axis/drill_5axis.

• Define the material Block to the component limits and view the model along the

Y-Axis.

Any cylindrical surfaces within the selection will automatically be recognised as Hole Features. The orientations of the Holes are controlled with the top being the closest to

the Max or Min, Z dimension of the Block.

It is possible to Reverse the Holes in a Feature Set using the local Edit options

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• Reset the Rapid Move Heights (Safe Z, Start Z) and then, set the Start

Point as Automatic – Block Centre Safe Z.

• Select all the surface data in the graphics window and then right mouse click

Feature Sets in the PowerMILL Explorer.

• Select the option Preferences.

This will open the Feature Form.

• Create the Feature Set entering the values into the form Exactly as shown

Multiaxis option selected.

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Any cylindrical surfaces within the selection will automatically be recognised as Hole Features.

• Undraw the model to view the newly created features.

Hole features are defined with a specific top and bottom.

Top of hole (no cross)

Bottom of hole (crossed)

The orientations of the Holes are controlled with the top being the closest to the Max or Min, Z dimension of the Block. On closer inspection three of the hole features have an incorrect orientation. These are to be to be reversed.

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• Select the Three incorrectly orientated holes.

• Right mouse click over the Feature Set in the explorer window. • Select Edit, Reverse holes.

All holes now have the correct orientation and are ready for drilling. • Create a 5mm drill of length 90.

• Add a holder component Upper dia 50 lower dia 30 length 30 overhang 80 • Add a holder component Upper dia 50 lower dia 50 length 30

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• Select the Toolpath Strategies icon and select the Drilling option located in

the New strategies form.

• Rename the toolpath 5mm drill.

• In the Drilling form click the Select tab to open the Feature Selection form.

• Select and Close the Feature Selection form.This will select all the diameters from the list.

• With the Multiaxis option selected on the drilling form Apply and Close to create the drilling toolpath.

• Animate the toolpath.

The multiaxis licence enables the user to create a single feature set from components that lie in different workplanes and machine them in one go.Without the licence the recognise holes in model option can be used from the feature set menu to create the hole features.This command splits the features by alignment but also creates separate

workplanes with the Z axis aligned to each Feature Set.

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The two 6mm Hole Features are to be Tapped. The point angle of the 5mm Drill has left a conical shape at the bottom of the holes. When the holes are Tapped it will be necessary to stop short within the full diameter range by applying a suitable Axial Thickness value. • Create a 6mm Tapping Tool of length 25.

• Add a Shank, Upper - Dia 4, Lower Dia 4, Length 40

• Add a Holder, Upper- Dia 30, Lower Dia 30, Length 20, Overhang 60. • Select the two 6mm Hole Features in the Graphics Window.

• Select the Toolpath Strategies icon followed by the Drilling option located

in the New strategies form.

• Rename toolpath 6mmtap.

• Set Cycle Type - Tapping, Operation - Drill to Hole Depth, and Pitch - 1mm. • Input an Axial Thickness value of 5mm.

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• View the model along the –Y axis.

• Right click over the 6mmtap toolpath in the Explorer window and select Attach

Active Tool to Start.

• Left click in the graphics window and use the Right/Left Cursor keys to step through the toolpath.

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2. Five Axis Tool Alignment

Introduction

In 5-Axis applications where the machine tool head and/or table, rotates simultaneously with

the linear axis movements, PowerMILL provides a range of suitable Tool Alignments and Machining Strategies.

5-Axis machining enables components normally requiring a series of 3-Axis operations to be

machined in one set-up. Tools can be re-aligned using 5-Axis control to provide access to the

base of steep or undercut features, which are otherwise inaccessible down the Z-Axis.

In 5-Axis applications it is essential that suitable Leads, Links, and/or 3d limiting

techniques are applied to correct any problems identified by the default gouge check. In all cases it is also advisable to carry out a thorough visual inspection of the results.

Five Axis Tool Alignment and Machining Options

Not all PowerMILL Machining Strategies directly support Five Axis Tool Alignments but

those that do are shown highlighted in the Toolpath Strategies - Finishing options

shown below.

Machining Strategies that do not directly support Five Axis Alignments can be made to do

so by the application of Pattern finishing (with appropriate options set) as a secondary

operation on the original toolpath.

By default the Tool Axis in PowerMILL is set to Vertical for 3-Axis applications.

Tool alignments for use with 5-Axis operations are available via the Tool axis icon

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Lead/Lean

Lead allows the tool to be aligned to a specified angle along the toolpath direction and Lean

a specified angle across the toolpath direction. If both angles are zero the tool will be aligned

along the normal of the toolpath. The normal of the toolpath is the direction along which it

is projected onto the surface data during creation. For Pattern finishing this will always be

vertical and for Projection Finishing it will vary depending on the local projection direction.

• Create a Block to the sizes displayed in the table.

Min Max

X -50 50

Y -25 25

Z 0 10

• Reset safe Z heights and Start point.

• Right Click the Models option in the Explorer Window and Create a Plane from Block at a Z limit of 0.

• Create a 5mm ballnose tool of length 50 and rename 5bn.

• Create a Raster Finishing Strategy, Rename - Raster Vertical, and set Tol 0.02

Thickness 0 Stepover 5 Angle 0 Style Two Way Short Links On Surface

• Apply the toolpath and Cancel to close the form. • Animate the Toolpath.

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A raster toolpath has been created with the tool aligned vertically to the plane.

• Right Click the Toolpath Raster Vertical in the Explorer Window and select Settings to open the toolpath form.

• Make a Copy of the toolpath and rename Raster Lead@-30. • Select the Tool axis icon to open the Tool Axis Direction Form. • Define the Tool Axis as Lead/Lean with the Tool Lead Angle set to –30.

• Accept the Tool Axis Direction Form, Apply the toolpath and Cancel to close the form.

• Animate the Toolpath.

A raster toolpath has been created with the tool axis direction set to Lead -30° Along the Toolpath.

Using the Two Way option the tool axis direction

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View from left -X • Right Click the Toolpath Raster Lead@-30 in the Explorer Window and select

Settings to open the toolpath form.

• Re-cycle the toolpath and change Style from Two Way to One Way. • Apply the toolpath and Cancel to close the form.

With the Style set to One Way the tool axis direction

remains constant.

• Right Click the Toolpath Raster Lead@-30 in the Explorer Window and select Settings to open the toolpath form.

• Make a Copy of the toolpath and rename Raster Lean@45. • Select the Tool axis icon to open the Tool Axis Direction Form.

• Define the Tool Axis as Lead/Lean with the Tool Lead Angle set to 0 and Tool Lean Angle of 45.

• Accept the Tool Axis Direction Form, Apply the toolpath and Cancel to close the form.

• Animate the Toolpath.

A raster toolpath has been created with the tool Axis direction set to Lean 45° Across the Toolpath.

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Example2

• Import model 3plus2b.dgk from the local directory five_axis/3plus2b_as_5axis.

• Create the material Block to component size. • Define a 15mm diameter Ball Nose cutter (bn15). • Input a Safe Z of 185 and Start Z of 180.

• In the tool Start Point form set Mode: Fixed and Start Point: Absolute and enter the Coordinates: X-100 Y0 Z190.

• In the Main Toolbar set the Tool Axis - Lead/Lean values both set to 0. This will force the tool to be aligned along the projection direction of the machining strategy onto the model.

• Set Leads/Links as follows:-

Zheights: --- Skim 15 Plunge 5

Lead In/Out: --- Vertical Arc: Angle 90 Radius 6 Links: --- Short/Long/Safe: Skim

• Select the Toolpath Strategies icon and select the Finishing tab located in the strategies form.

• Enter the values into the Plane Projection Finishing and Tool Axis forms exactly as shown on the following page and Apply.

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Set One Way

• Animate the toolpath and observe the associated cutter alignment.

The resultant toolpath starts at the lower corner and climb mills upwards with a lead in and lean out angled.

To compare the effect of applying a different machining strategy the same area of the component will be machined using Raster Finishing. This time the Tool Axis will be

aligned with a Lean of 30 degrees relative to the downward projection of the Raster Finishing strategy.

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• Select the Fillet surface and the Spherical surface attached to it.

• With the Two surfaces selected Calculate a Block and Modify the values to read Xmin -70 Xmax -45 Ymin -50 Ymax 50

• Select the Toolpath Strategies icon and select the Finishing option located in the strategies form.

• Open the Raster Finishing and Tool Axis forms and enter data exactly as shown below and Apply and then Cancel.

The resultant toolpath starts at the lower corner and climb mills upwards with a lead in and lean out angled.

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• View along the Y-Axis and Animate both toolpaths in turn to compare the results of the lead/lean option. Note the tool alignment is the same for both toolpaths due to a suitable Lean value of 40 being applied to the Raster strategy.

Lead/Lean is designed for unidirectional toolpaths the main application being to maintain a

suitable angle of the Tool Axis away from steep features as well as the machine tool table.

The lower part of the component form in the next example is an ideal application for applying a suitable Lean value using Lead/Lean - Tool Axis alignment.

Example 3

• Import the model joint5axis.dgk from the directory PowerMILL_Data/five_axis/joint_5axismc.

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• Create the material Block to component size and expand by 15mm in X and Y only.

• Define a 25mm diameter Ball Nosed cutter (bn25). • Reset Safe Z and Start Z.

• In the Start Point set Mode: Automatic and Start Point: Block Centre safe Z. • Modify Leads/Links as follows:-

Zheights: Skim 45 Plunge 10 Links: Skim.

• Open the Line Projection Finishing and Tool Axis forms and enter data exactly as shown and Apply.

Set: Lead 0 Lean -30

The resultant machining is illustrated below after the appropriate gouge protection has been applied (Leads/Links) as specified earlier.

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Note: The next section continues with the machining of the above component.

Toward / From Point

These options allow the Tool Axis alignment to be based on a user-defined point during the

generation of toolpaths. The alignment is towards the Preview pattern for the toolpath and

not the actual toolpath. Toward Point is suitable for aligning to external forms (Upstands)

while From Point is suitable for aligning to internal forms (Pockets). The upper part of the

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Note:- The same alignment condition (above) applies to Toward / From Line (page 8). • Set Leads/Links as follows:-

Lead In; --- Horizontal Arc Angle 90 Radius 6.0 Lead Out: --- Vertical Arc Angle 90 Radius 6.0 Extensions; --- Inwards/Outwards Extended Move Distance 30 Links; --- Skim

• Open the Point Projection Finishing and Tool Axis forms and enter data exactly as shown on the following page and Apply.

Note the Tool Alignment point is approximately 10mm below the Projection Finishing

focal point to ensure that the spindle axis remains at an elevation angle to the machine tool table during machining hence avoiding collision.

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Toward Line / From Line

These options allow tool axis alignment to be based on a user-defined line, specified by point and Vector, during the creation of the 5-Axis toolpath. The alignment is towards the preview

pattern for the toolpath and not the actual toolpath. Toward Line is suitable for aligning to

external forms (Upstands) while From Line is suitable for aligning to internal forms

(Pockets).

• In the Explorer select Model -Delete All.

• Import the model 5axisdie.dgk from the local directory five_axis/die_5axismc.

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• Continue to use the same 25mm diameter Ball Nose cutter. • Define the material Block to the component limits.

• In the Start Point set Mode: Automatic and Position: Block Centre safe Z. • Reset Safe Heights.

• Set all Leads and Extensions to None, Zheights Skim to 5 and Plunge to 5. • Select the Toolpath Strategies icon and select the Finishing tab located in

the strategies form.

• Open the Line Projection Finishing and Tool Axis forms and enter data exactly as shown on the following page and Apply.

One Way (ticked)

The end result is as shown in the following illustration (Links reset to Skim).

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• Animate the generated toolpath and then open Leads and Links form entering values as set out in the following table:

Lead In -- Extended Move Distance 10.0 Lead Out -- Extended Move Distance 20.0

Extensions -- Inward/Outward Vertical Arc Angle 90.0 Radius 10.0 Links -- Short Skim

-- Short/Long Threshold 10.0 -- Long Safe Z

-- Safe Skim • Apply the Leads and links form.

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Fixed Direction

This allows the tool axis to be set to a fixed angle, specified by Vector, defined by the user. In this case it is applied to the finishing of an undercut form on the 5axis_fixture.dgk model.

• In the Explorer select Model -Delete All. • Reset forms.

• Import the model 5axis_fixture.dgk from the local directory five_axis/ Autorail_and_Fixture

• Create a 16 Ball nosed cutter (16bn). • Set all Leads and Extensions to None.

The model consists of components constructed on two levels, Fixture: surfs and Part: surfs,

that can be drawn an undrawn by opening the Levels form in the Explorer window. To

demonstrate an application of the fixed direction alignment, only the Fixture: surfs level

needs to be drawn.

• Undraw the Part: surfs level from within the explorer window.

Note: Even undrawn surfaces are still registered in PowerMILL and will be machined. To

stop this, you can acquire the level to the Components list and then ignore it when the

toolpath is calculated.

• Activate the workplane Car line datum.

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Location to be machined (Block drawn)

Fixed Direction Tool Alignment – Vectors/Angular equivalents The table represents angular directions and vectors on the XY plane (Z=0).

ANGLE VECTORS (Degrees) (I J K) 0 1 0.0000 0 5 1 0.0875 0 10 1 0.1760 0 15 1 0.2680 0 20 1 0.3640 0 25 1 0.4660 0 30 1 0.5770 0 35 1 0.7000 0 40 1 0.8390 0 45 1 1.0000 0 50 1 1.1920 0 55 1 1.4280 0 60 1 1.7320 0 65 1 2.1450 0 70 1 2.7470 0 75 1 3.7320 0 80 1 5.6710 0 85 1 11.4300 0 90 0 1.0000 0

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The tool axis is oriented in a fixed direction relative to the currently active workplane defined by a specified IJK vector in the Tool Axis direction form. Although it can be difficult to

work out the required IJK vector, this option can enable you to machine undercut areas very

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• Open the Line Projection Finishing and Tool Axis forms and enter data exactly as shown below.

Draw Toolaxis (ticked)

• Select the Thickness icon and then the Components tab to access the Component Thickness form.

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• Select the level Part: surfs from the pull down level selector.

• Acquire the selected level to the Component Thickness list. • Select Ignore from the machining mode pull down option.

• Accept the form and Apply the Toolpath. • Animate the Toolpath.

The tool axis is fixed to the direction specified by the IJK vector. By setting the machining mode to ignore for the part surfaces only the fixture is machined. The tool axis has also been drawn indicating the vector direction.

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3. Projection Surface Finishing

Introduction

The toolpath is projected along the normals of a Reference Surface onto the main

component with tool alignment as specified by the user. The toolpath runs either across or along the Reference Surface directions (U or V) with the Stepover being defined by unit Distance or Parametric division between Surface Curves. In some cases the Reference Surface may form part or all, of the component to be machined.

To create a Reference Surface the user will require the services of a suitable Surface Modeller, ideally PowerSHAPE. For the following example the Reference Surface has already been created and stored as a separate dgk file to be imported as required.

• Import in two models joint5axis.dgk and joint_ template1.dgk from the local directory PowerMILL_data/five_axis).

• Create a Block to the component dimensions. • Define a 16mm diameter Ball Nosed cutter. • Reset Safe Z and Start Z.

• In the Start Point set Mode: Automatic and Position: Block Centre safe Z. • In the Leads and Links form set Short Links to On Surface and Long/Safe

Links to Skim adjusting the Zheights to a Skim distance of 30 and Plunge

distance of 5.

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• Select the Toolpath Strategies icon in the Main toolbar to open the strategies

form.

• Select the Finishing tab followed by the Projection Surface Finishing option. • Enter the values into the Surface Projection Finishing and Tool Axis forms

exactly as shown below and Apply.

Enter the Name - ref1_U

Set One Way

With Pattern Direction set to U the toolpath will appear along and aligned to the Reference Surface - Longitudinal direction (as shown below).

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• Do not close the form after processing is complete but select the Copy icon to re-activate the settings and input the new Name - Ref1_V

• Untick the box One way, set the Pattern Direction to V and select Apply.

This time the toolpath will appear along and aligned to the Reference Surface - Lateral direction (as shown below).

Both the above toolpaths have a stepover based on a unit Distance value across the

Reference Surface. The Finishing form will now be amended to use Parametric division. • Delete the Reference Surface – joint_ template1.dgk and as a replacement,

Import - joint_ template2.dgk and make sure that it is selected.

• Apply another Copy of the Surface Projection toolpath named Ref2_U with

Surface Units - Parametric, Pattern Direction - U, and Stepover - 0.1.

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The Stepover - 0.1 creates 10 equally spaced tool tracks between each pair of Reference Surface – Curves parallel with the machining direction.

To even out large variations in Stepover across the component the Reference Surface requires the addition of extra, suitably placed curves.

A modified copy has already been created in PowerSHAPE to replace the current

Reference Surface as instructed below.

• Delete the Reference Surface – joint_ template2.dgk and as a replacement,

• Apply a Copy of the above Surface Projection toolpath named Ref3_U to create the following result.

The new toolpath contains a consistant

Stepover.

To provide full flexibility for the shape of the Reference Surface it is possible to

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This is achieved by setting the Finishing strategy Component Thickness option to Ignore it during the actual toolpath projection (it is still used to control the Tool Axis

alignment).

• Delete the Reference Surface - joint_ template3.dgk and as a replacement,

Note: Most of the new Reference Surface

exists outside the component to be machined. Also this surface is inside out (shaded dark brown).

• Start a Copy of the Surface Projection toolpath named Ref4_U with Surface

Units - Distance, Projection Outwards, Pattern Direction - U, Stepover – 1.0

and One Way ticked.

• Select the Thickness icon to access the following form (shown on the following page).

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• Select one of the rows in the form, set Machining Mode to Ignore, and with the

Reference Surface still selected click on the Aquire Components icon.

Select a row.

Set the MachiningMode

to Ignore.

Click the Aquire Components icon.

The row will display the value 1 in the Components category to show that a single

surface has been assigned to it.

• Accept the above form and then Apply the Surface Projection Finishing form to produce the following toolpath.

Note: The Reference Surface used to provide

the Tool Alignment has

been ignored during the toolpath projection onto the component.

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Surface Projection Range.

It may be required, on occasion, to limit the projection range whilst applying the Surface Projection strategy. This can be necessary if the surface to be machined is within close proximity to other surfaces that do not require machining or are affecting the surface projection results. This command is, at present, only available on Preview via typed input into the Command Window.

Note: Preview features are provided for you to evaluate and should NOT generally be used for production work. Delcam makes no guarantee that the behaviour of Preview features will be preserved when they are released.

• Import the model Blade Inserts.dgk from the local directory

PowerMILL_data/five_axis/Blade_Sub_Assembly

• Create a Block to the component dimensions.

• Define a 6mm diameter Ball Nosed (6bn) cutter of Length 30. • Create a Shank with Upper Dia 6 Lower Dia 6 Length 20. • Create a Holder with Upper Dia 20 Lower Dia 16 Length 30

• Add a Holder component Upper Dia 30 Lower Dia 30 Length 20 Overhang 40 • Reset Safe Z and Start Z.

• Set Start Point Mode:Automatic and Position:Block Centre safe Z. • Set Leads and Links as follows

Lead in/out Horizontal arc Distance 0 Angle 90 Radius 3 Extensions

Links Short/Long/Safe Skim.

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• Select the Blade Surface to be machined (shown shaded below).

• Select the Finishing tab followed by the Projection Surface Finishing option.

• Enter the values into the Surface Projection Finishing and Tool Axis forms

exactly as shown below and Apply.

Rename – default_projection_range.

One way Set

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With the projection set to default, ie. No limit, the toolpath is projected inwards towards the surface to be machined from the extremity of the model limits. As the toolpath is projected it will encounter the neighbouring surfaces before the surface to be machined and create the toolpath as shown.

Projection Range

Contour Produced

This problem can be resolved by specifying a limited distance, usually the radius of the cutter, as the projection range.

• From the View menu at the top of the screen Select the option Toolbar -

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• Select Settings from the toolpath in the explorer window and make a Copy of the original toolpath.

• Rename the toolpath 3mm_projection_range.

• Click the mouse into the Command Window at the bottom of the screen and

enter the following commands.

EDIT SURFPROJ AUTORANGE OFF EDIT SURFPROJ RANGEMIN –3 EDIT SURFPROJ RANGEMAX 3

This command sequence limits the Surface Projection distance range to + / - 3mm.

• Apply the form to calculate the toolpath. • Animate the toolpath to observe the effect of

the limited projection range.

EDIT SURFPROJ AUTORANGE ON

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4. Five Axis Pattern Finishing

Introduction

The following Finishing strategies; 3D Offset, Constant Z, Optimised Constant Z, Pencil, and Corner, are examples that do not directly support 5-Axis Tool Alignments.

A 5-Axis conversion is achieved by re-machining using the Pattern finishing strategy. If Base Position - Automatic is specified the toolpath will be recreated to the selected 5-Axis Tool Alignment (as illustrated below).

Original

Vertical Alignment

New 5-Axis Alignment

Corner Finishing - conversion to 5 Axis

• Import the model pocket_sld.dgk from the local directory

PowerMILL_data/five_axis/vert_pocket.

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• Create a Block to the component dimensions. • Define a Ball Nosed tool 8mm diameter. • Reset Safe Z and Start Z.

• In the Start Point set Mode: Automatic and Position: Block Centre safe Z. • Select the Toolpath Strategies icon and select the Finishing option located in

• Enter the remaining values into the Corner Pencil Finishing form exactly as shown below and Apply.

Note: Five Axis tool alignment

options are not directly available with the Corner Pencil Finishing

strategy (shown below).

The resultant 3-Axis toolpath can

however be machined using the

Pattern Finishing strategy set to

recreate the original toolpath as a

5-Axis Tool Alignment.

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• Select the Toolpath Strategies icon and select the Finishing option located in

• Enter the remaining values into the Pattern Finishing and Tool Axis forms exactly as shown below and Apply.

As displayed on the form the

Use Toolpath box is ticked,

the original Toolpath is

selected as the Pattern, and

the Base Position is set to

Automatic for the 5-Axis Tool Alignment to work.

The resultant 5-Axis toolpath

is shown below with the original 3-Axis tooltrack

(inside).

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• Apply Leads/Links as follows:-

Lead In/Out: --- Vertical Arc Angle 90 Radius 6

Extensions: --- Inward/Outward Extended Move Distance 5 Links: --- Short/Long/Safe: Skim

• Animate the active toolpath to display the 5-Axis tool movement and the contact points between both the base and sidewalls of the pocket as shown below.

Corner Finishing - conversion to 5 Axis

The previous example involved a unidirectional toolpath to 5-Axis, Pencil machine the intersection of the sidewalls with the base of a pocket. In this case the 5-Axis Tool

Alignment was achieved using Lead/Lean with values of 0 and 20 respectively. This would not be an option for a bi-directional toolpath due to Lead/lean being dependant on the direction (The Lean of the tool would keep switching sides on the alternate toolpath

direction). For the following Stitch Corner example a From Point - 5-Axis Tool Alignment is applied which is not affected by the toolpath direction.

This example uses the same settings as before using the original 8mm Ball Nosed cutter for the machining process.

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• Define a Ball Nosed tool 16mm diameter to be used as the Reference Tool.

• Enter the remaining values into the Corner Stitch Finishing form exactly as shown below and Apply.

Note: Five Axis tool alignment

options are not directly available with

the Corner Stitch Finishing strategy

(shown below).

The resultant 3-Axis toolpath can

however be used in a Pattern Finishing strategy set to recreate the

original toolpath as a 5-Axis Tool Alignment.

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As displayed on the form the Use Toolpath box is ticked, the original Toolpath is selected as the Pattern, and the Base Position is set to Automatic for the 5-Axis Tool Alignment to work.

The resultant 5-Axis toolpath is

shown below.

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• Apply Leads/Links as follows:- • Zheights: --- Skim 5 Plunge 5

• Lead In/Out: --- Vertical Arc Angle 90 Radius 3 • Extensions: --- Inward/Outward None

• Links: --- Short/Long/Safe: Skim

• Animate the active toolpath to display 5-Axis tool movement and the contact points between both the base and sidewalls of the pocket as shown below (Leads

and Links not displayed for clarity).

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Corner Finishing – conversion to 5 Axis (continued) • Open the Project Corner_finish from the local directory

PowerMILL_data/five_axis/5axis_Corner_Finish/Corner_finish

The Project contains a single corner finishing toolpath strategy calculated using a 4mm ball nosed tool assembly referenced against an 8mm ball nosed cutter.

By Attaching the Active Tool it is clearly visible that the bottom of the pocket is unable to be machined safely using the current tool assembly. This can be confirmed by verifying the toolpath.

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• Right click over the toolpath 4mm_corner finish in the explorer window and select Verify from the list.

• Enter the values into the form exactly as shown and Apply.

PowerMILL will check the toolpath for collisions using the 4bn tool assembly. The toolpath will be divided into safe and unsafe moves with safe moves machined using the current 4bn tool and unsafe moves machined with an automatically created tool called 4bn_1. This newly created tool is a replica of the original tool assembly, with a modified overhang value, to enable the bottom of the pocket to be machined without collision.

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Therefore to machine the pocket using vertical tool alignment it is necessary to introduce an additional ‘extended’ tool. However, using the extended tool raises further issues i.e.

Increased tool deflection, reduced cutting speed etc. all of which may not be acceptable to the user. Altering the tool alignment will make it possible to machine the pocket with the original tool. Five Axis tool alignment options are not directly available with the Corner Stitch Finishing strategy. The 4mm_corner finish_2 3-Axis toolpath can however be used in a Pattern Finishing strategy set to recreate the original toolpath as a 5-Axis Tool Alignment. • Select the Toolpath Strategies icon and select the Finishing option located

in the strategies form.

As displayed on the form the Use Toolpath box is ticked, the

4mm_corner finish_2 Toolpath is selected as the Pattern, and the Base Position is set to Automatic for 5-Axis Tool Alignment to work.

• Accept the form. • Animate the Toolpath.

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The tool can be seen to be leaning away from the walls of the pocket thus avoiding any collision. This can be confirmed by verifying the toolpath.

• Right click over the toolpath 4mm pattern corner finish in the explorer window and select Verify from the list.

• Use the values stored within the form from its previous application and Apply. PowerMILL will confirm that the toolpath is collision free.

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Constant Z Finishing - conversion to 5-Axis

• Import the model punch2_insert.dgk from the local directory

PowerMILL_data/five_axis/punch2.

Initially a 3-Axis, Constant Z finishing strategy will be created, which when checked will be found to be in collision with the

component form. The strategy will then be re-machined as a Pattern finishing strategy along with a suitable 5-Axis, Tool Alignment. A full collision check will again be performed on the final toolpath.

• Create a Block to the component dimensions. • Reset Safe Z and Start Z.

• In the Start Point set Mode: Automatic and Position: Block Centre safe Z. • Create a Ball Nosed tool Dia 20, Length 100, Name bn20 as shown in the

following form.

• Add a Shank with Upper Dia 30, Lower Dia 20 and Length 50.

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• Activate the Ball Nosed, bn20.

• Select the Sidewall Surface (shown shaded dark below) and Create a Selected

Surface Boundary with the name constZ.

• Enter the remaining values into the Constant Z Finishing form exactly as shown below and Apply.

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• Attach the Active tool, bn20 to a point along the base of the toolpath near to the highest point of the model to observe the expected Collision condition.

• Enter the remaining values into the Pattern Finishing form exactly as shown below and Apply.

As displayed on the form the Use Toolpath box is ticked, the original Toolpath is selected as the Pattern, and the Base Position is set to Automatic for the 5-Axis tool alignment (Lead 0, Lean 30) to work.

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The resultant toolpath (shown below) is a 5-Axis version of the original Constant Z strategy.

• Open the Collision checking form by selecting the icon in the top toolbar. • Select the option Check Collisions.

• Set Scope All.

• Uncheck Split Toolpath.

• Apply the form to receive the following message confirming that the toolpath is collision safe.

The lower fillet is yet to be machined and again requires a suitable 5-Axis strategy to avoid a collision situation (This will be covered later in Chapter 9 - Tool Axis Limits).

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-5. Five Axis Profile Machining

Introduction

The Profile Finishing strategy can be applied to Five Axis applications. In the following example it will provide a Tool Alignment normal to a user defined, surface flowing inwards at 90 degrees to the base of an angled pocket. Note, the Profile Strategy, controlling surface is not necessarily the actual base of the pocket.

• Import the two models, locnpad.dgk and pocket.dgk (shown shaded) from the local directory PowerMILL_data/five_axis/locnpad_5axismc.

• Delete the locally defined top surface covering the pocket. • Create a Block to the component dimensions.

• Activate the 16mm diameter Ball Nosed cutter. • Reset Safe Z and Start Z.

• In the Start Point set Mode: Automatic and Position: Block Centre safe Z. • Select the Toolpath Strategies icon and select the Finishing tab located in

• Enter the remaining values into the Profile Finishing and Tool Axis forms exactly as shown on the following page and Apply.

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• Select the surface defining the base of the pocket, click Apply and after the toolpath is processed Cancel the form.

• The following toolpath is created in which the tool is constantly aligned to the sidewalls for each profiling pass, the final pass being exactly on the base.

Note:- the Reference Surface has been specially designed to create a Tool Alignment that is always parallel with the sidewalls of the pocket with Lead/Lean 0.

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• Animate the toolpath and observe the Tool Alignment normal to the Reference

Surface (as well as parallel to the sidewalls).

• Import the additional model flat_pktbase from the same directory as before. • Right mouse click the toolpath and select Settings to reopen the Profile Finishing

form.

• Select the icon to ‘Create a new toolpath based on this one’ . • Ensure that the original base surface still selected as the Reference Surface. • Click Apply and after the toolpath is processed Cancel the form.

The tool is still aligned to the lower (selected) Reference Surface but this time the profile tooltracks are limited by the upper base surface.

The next example shows how Profile can be used to ‘swarf’ machine the sidewalls of the component. After the calculation of the tool tracks additional limiting will be required to leave just a single track around the base.

• Right mouse click the latest toolpath and select Settings to reopen the Profile

Finishing form.

• Select the icon to ‘Create a new toolpath based on this one’ . • Select the outer sidewall surface of the component (shown shaded below), right

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• Update the remaining values in the Profile Finishing and Tool Axis forms to be exactly as shown below and Apply and after the toolpath is processed Cancel the

form.

Gouge Avoidance:- Strategy Trace Upper Limit ‘box unticked’ Multiple Cuts :- Mode Off

Lead/Lean:- Lead 0 Lean -90

• Apply Leads/Links as follows:-

Lead In/Out: --- Horizontal Arc Angle 90 Radius 10 Links: --- Short/Long/Safe: Skim

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The resultant toolpath must now be modified to leave the single track around the base.

• Select the unwanted, upper tool tracks (arrowed) using the left mouse key and then right mouse click to open the specific, toolpath menu.

• Select Edit -> Delete Selected to retain only the single lower tool track.

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6. Embedded Pattern Finishing

Introduction

This strategy allows the user to produce an Embedded Pattern Finishing Toolpath using an Embedded Pattern to define the contact points of the toolpath. An Embedded Pattern is a curve lying on the model linked to its associated surface (or surfaces).

An Embedded Pattern Finishing toolpath can be used to specify the exact position of contact point or to use information about the underlying surface (for example surface normal) to determine the Tool Axis orientation when engraving.

Embedded Pattern Finishing – Engraving

• Import the model Embedded.dgk from the local directory

PowerMILL_data/five_axis/ 5axis_Embedded_Pattern.

• Create a Block to the component dimensions. • Reset Safe Z and Start Z.

• In the Start Point set Mode: Automatic and Position: Block Centre safe Z. • Create a Taper Tipped Form tool Dia 5 – Tip rad 0.5, Length 25, Taper height

15, Taper Angle 7.5,Name TTR 0.5

• Add a Shank with Upper/Lower Dia 5 and Length 10.

• Add a Holder with Upper Dia 30, Lower Dia 20 and Length 5. • Add a Holder with Upper Dia 30, Lower Dia 30 and Length 20.

• Right click over Patterns in the Exporer Window and select Toolbar to display the Pattern toolbar at the top of the screen.

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The Pattern contains the Text DELCAM positioned above the component surfaces. It then needs to be embedded before it can be used.

• Rename the Pattern ‘Text’

• Right click the Patterns menu in the explorer window and select Edit – Embed.

The Embedded Pattern dialog is displayed.

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An Embedded Pattern called Text_1 is created marked by in the explorer. The original pattern is also kept.

• Select the Toolpath Strategies icon and select the Embedded Pattern Finishing option located in the strategies form.

• Enter the values into the Embedded Pattern Finishing form exactly as shown and

Apply.

• Select the Embedded Pattern

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• Animate the toolpath.

The embedded toolpath has been produced normal to the surface but the toolpath has been highlighted in the explorer window with a warning. This is because the lowest toolpath segments intentionally cut into the surface to produce the engraving. To remove the warning the toolpath would have to be gouge checked. This can be applied from within the Embedded Pattern Finishing form, however by applying this the lowest toolpath segments will be removed.

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7. Five Axis Swarf Machining

Introduction

The Swarf Finishing option creates a toolpath where the selected surfaces are machined with the side of the tool (Tool Alignment is automatic). A Swarf Finishing toolpath will only exist where the tool is able to remain in contact with the surfaces for the whole cutting depth. The surfaces to be machined must be Swarfable (Not Convex or Concave but Linear relative to the resultant tool alignments)

• Import the model swarf_model.dgk (shown shaded) from the local directory

PowerMILL_data/five_axis/swarf_mc.

• Create a Block to the component dimensions. • Create a Dia 12mm x 1tip radiused cutter. • Reset Safe Z and Start Z.

• In the Start Point set Mode: Automatic and Position: Block Centre safe Z. • Change the View to ISO 4 and select the local surfaces to be Swarf machined

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• Enter the values into the Swarf Finishing form exactly as shown below and Apply (Note:- Tool Alignment is automatic for this option).

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• Open the Leads and links form via the icon , and Apply the settings as

illustrated in the following table:-

Z Heights: Skim distance 20.00 -- Plunge distance 5.0

Lead In: Horizontal Arc – Angle 90 – Radius 6.0

Lead Out: Horizontal Arc – Angle 90 – Radius 6.0

Links: Short/Long/Safe –Skim

• Deselect the local surfaces, Animate the resultant toolpath and observe the changing angle of the tool as it Swarf machines the selected surfaces (Toolpath

shown on previous page).

• Using the Right mouse key select the toolpath in the explorer to open the pull down menu the top half of which is shown below left.

• Use the Left mouse key to pick the option Select Surfaces, which will prompt the actual surfaces used during the toolpath creation to become selected again.

• Create a Dia 10mm End Mill

• Using the same settings in the Swarf Finishing form create a machining path aligned to the underside of the recess on the outer sidewall (selection and resultant toolpath shown on the following page).

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• Deselect the local surfaces, Animate the resultant toolpath and observe the changing angle of the tool as it Swarf machines the selected surfaces.

• Select the multiple group of surfaces as shown below and modify the settings as shown below in the Multiple Cuts area to the lower right of the Swarf Finishing

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• Deselect the local surfaces, Animate the resultant toolpath and observe the

changing angle of the tool as it Swarf machines the selected surfaces in a series of

multiple cuts.

• Use the Left mouse key to pick the option Select Surfaces, which will prompt the actual surfaces used during the toolpath creation to become selected again. • Modify the settings as shown below in the Gouge Avoidance and Multiple Cuts

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Radial and Axial Thickness

• In The PowerMILL Explorer - Delete the current Model and all Toolpaths. • Import the models locnpad.dgk and pocket.dgk (shown shaded) from the local

directory PowerMILL_data/five_axis/locnpad_5axismc.

• Delete the top surface covering the pocket. • Create a Block to the component dimensions. • Reset Safe Z and Start Z.

• In the Start Point set Mode: Automatic and Position: Block Centre safe Z. • Activate the Dia 10 End Mill.

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• Select the Swarf Finishing form and select Radial/Axial Thickness form via the icon (as shown below).

• Tick the box Use Axial Thickness and enter the Thickness settings as Radial 0

and Axial 3.

• Select the local Surface defining the wall of the pocket (shown below) and after entering the remaining settings (as shown in the above left) Apply the Swarf Finishing form.

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3mm Axial Stock

• Create another similar Swarf Finishing strategy apart from swapping the

Thickness settings to Radial 3 and Axial 0.

3mm

Radial Stock

• View along the Y Axis to Compare the results as shown in the above two illustrations.

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8. Four Axis Rotary Machining

Introduction.

This Finishing strategy is designed for machining a component mounted on a fourth, programmable Rotary Axis. During milling, the component rotates around the rotational X-axis while the cutter performs simultaneous 3-Axis movements.