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Multi Axis Machining
한국델켐주식회사
정 찬 웅
What is multi axis machining?
• 4- axis• Positional 5-axis• Continuous 5-axis• Swarf machining
Benefits of 5-axis Machining
• Reduction of Setups• Improved surface finish• Allows machining of undercuts• Improved tool life• Less EDM required• Less bench work required• Shorter manufacturing times for cavities
Why 5 axis machining
• Market requirements for– Increasing flexibility– Improved productivity– Improvements in surface finish
• Technology advances in machine tools• Affordability of machine tools• Trend to machine shorter batch runs from
solid material– Linked to ever shorter product life cycle
Forecasted Use of 5-axis Machines by Worldwide
Mouldmakers
Remain steadyIncrease slowlyIncrease quickly
36.8%
57.9%
5.3%
Source : CIMdata April 2000
Application Areas
• Aerospace– Structures– Turbine?
• Turbine blades• Tool and die• Medical• Automotive• Marine
Aerospace structure
Thin walled angled wallsThat require swarf machiningWith cutter fanning round the corners
Fanning
Aero EngineBlisk (Bladed DISC)
Turbine Blade
Tool and DieTrimming (profiling around edge)
Tool and Die
Marine
Medical
Hip Joint
Dental
Prosthetics
5-axis machining• Three basic types of machine: -
– Head/head– Head/table– Table/table
• Two machining approaches: -– Positional (3 + 2) and
continuous• 5-axis machining is much more
complex that 3-axis machining, e.g. wider variation in post-processing
PowerMILL 4All 5 Axis Machine Tools are based on 3 configurations
•All Movement in the Head •Movement in Head and Table•All Movement in Table
All OTHER CONFIGURATIONSARE BASED ON THESE
PowerMILL 4
THINGS TO CONSIDER
•Part Position on the table
•Software Constraints
•Physical constraints
PowerMILL 4
Part Position on the Table
Limits are set in the Option File
Positioning the Part could result in Not being able to reach all Areas
PowerMILL 4
Software ConstraintsFind out about the control•Type?•Coordinate transformation?•Linearization?
PowerMILL 4
Physical constraints•Linear and rotary limits?•Will the job fit on the machine? •Can you rotate the tool to get to all areas?
Typical Machine Tool Kinematics
• Two main types of 4 axis machining– Table rotation in C– Table rotation in B
• Three main types of 5 axis machines– Head rotation– Head rotation and table rotation– Table rotation in two axis
• Hexapod Type
What the letters mean
•On most machines, the A,B,and Caxes correspond to X,Y, and Z inthis way:
•The A axis pivots around a center line parallel to the X axis.
•The B axis pivots around a centerline parallel to the Y axis.
•The C axis pivots around a centerline parallel to the Z axis.
Head / Head type
Mecof fork typeHead rotation in C and A
Rye Gantry typeHead rotation in C and B
Head / Table Type
Head rotation in ATable rotation in C
Head rotation in BTable rotation in C
Table / Table Type
Head StaticTable rotates in CTable rotates in B
Mazak Variamatic
Table / Table Type (continued)
Head StaticTable rotates in CTable rotates in A(with A axis nutated)
DMG
Hexapod
View from above
5-Axis Positional Machining
• Machine head is aligned in a series of fixed positions
• Maximum rigidity as head is fixed during each machining stage
• Faster machining possible between head movements
Five-axis Positional Machining• Ideal for machining deep
cores and cavities• Undercut shading assists user
to orientate axes so avoiding collisions
• Short cutters give increased accuracy and higher quality surface finish
• Significant time benefits through reduced set-ups
Positional 5-axis (3+2 Machining)
73% of 5-axis users use 5-axis for positioning.(source: CIMdata April 2000 )
Five-axis Positional Machining
5 Axis Positional MachiningCompany DACMAC (UK)Machine DMU 50EReduction in operations from 12 to 2Parts now set off line (each set up Previously took 90 minutes). Positional 5 Axis with DMG and Delcam
has given Dacmac
• Quicker toolpath generation time• A reduction in costs• Improved flexibility• Improved accuracy • Better surface finish
Doong Ling Ltd., Taiwan• Major manufacturer of
moulds for bumpers• Uses 3 + 2 machining
for large moulds• “The high quality
surface finish produced with PowerMILL has reduced the time needed for hand finishing by 50%” Mr. Tsai, Owner
A.F. Gaskin, UK
• Mould maker and precision engineering
• Uses 5-axis to increase accuracy and reduce set-up times
• “5-axis machining saves a lot of time and money. It is essential to the future of our business” David Gaskin, Director
Continuous 5-Axis in PowerMILL
• Wide range of 5-axis strategies – through a line, through a point, profiling, trimming, pocketing etc.
• Automatic calculation of optimum lead and lag
• Gouge and collision checking on all toolpaths
• Supports full range of cutters
Tool axis direction
PowerMILL uses 5 different methods of orientatingThe tool axis.
Automatic Control of Lead and Lag Angles
Lead Angle- defines a rotation of theTool axis in the direction of travel, can bePositive or negative.
Automatic Control of Lean Angle
Lean Angle- defines a rotation of theTool axis at right angles to the directionof travel, can be positive or negative toIndicate a right/ left lean.
Towards a pointThe machining direction will always pass a point in space with thecutting end pointing towards the point at the start of the projection.
Pattern location
Plane Projection (pattern isPlane)
Pattern Location
Point/line projection (patternIs a sphere)
Towards a point
From a point
The machining direction will always passThrough a point in space with the cuttingEnd pointing away from the point at theStart of the projection.
Towards a line
The machining direction will always passthrough a user defined line in space withthe cutting end pointing towards the line. The tool axis is oriented towards a line at the Start of the projection.
Cutter Drive Issues
• Profiling keeps tool perpendicular to the edge at any particular point
• Drive surface machining keeps the tool parallel to the t or u direction at any particular point
• Swarf cutting keeps the tool parallel to the ruling direction at any particular point
Full Simultaneous 5 Axis Machining (Surface Normal)
5 Axis in PowerMILL
•The skirt of this Italian High Speed Train was manufactured using PowerMILL 5 Axis•Franco Calloni (Delcam Italia) used a combination of :-
•Positional 5 Axis [or 3+2]•5 Axis continuous with use of a reference surface as the drive curve.
5 Axis Machining using a Reference Surface as the drive
curve• Can be used as concept
prototype• Needs PowerSHAPE to
create the reference surface
• PowerMILL user can apply lead/ lean angle for tool that will use reference surface as the drive curve.
Drive Surface 5-axis
• Projection direction and tool orientation determined by drive surface
• Single drive surface but multi-surface part
• Full gouge protection• All cutter types
Video of 5 Axis Machining Using A Reference Surface
Machining normal to the surface
• Easiest method for programming but can be inefficient
• Only uses tip of cutter so wear is concentrated in a small area
• Contact is with centre of cutter so cutting speed is lower
• Can lead to greater movement of head than necessary
• Can be impossible to reach some areas without collisions
Swarf Machining
Swarf cutting is when you cut with the side of the tool. It can only work with developable surfaces where the ruling direction is perpendicular to the parametric direction you are machining along.
Machining with variable lead and lag
• Variation of cutting angle gives better cutting conditions and more even wear of cutter
• Head movement is reduced allowing faster machining
• Allows access to “difficult”surfaces without risk of gouging
5-axis machining of slots• Using 3-axis machining
with a ball-nose cutter will leave a fillet in the corners. The corner must then be finished by hand
• Using 5-axis machining with an end-mill, leaves a sharp corner, needing minimal hand finishing
• The reduction in hand finishing saves time and improves quality
5-axis machining of slots
5-axis profiling
• 5-axis profiling uses new-style cutters with longer flute length
• Allows smoother surfaces to be machined with fewer cutting operations
• Similar approach can be used for trimming e.g. of composite mouldings
Rojac, UK• Major supplier of models,
patterns and tooling to the automotive industry
• Uses 5-axis machining for deep cavities, trimming and drilling
• “With 5-axis machining, we can produce a better surface finish at a higher speed”Gerry Hart, CADCAM Manager
Rojac UK
5-Axis Drilling• CAM system can recognise
hole features defined in CAD system
• Main application in drilling holes at fixed angles to complex surfaces
• “For a typical component, we have reduced the drilling time from two days to an hour” Gerry Hart, CADCAM Manager, Rojac
5-axis Drilling
Benefits of Continuous 5 axis machining
• Ideal for profiling parts • Ideal for machining deep cores and cavities • Short cutters give increased accuracy and higher
quality surface finish • Allows for machining with the flank or bottom of the
tool • Can be used with a full range of tool types • Full gouge protection • Can be used with models in STL format (with the
exception of profiling)
5-axis machining of bottle
Machining of V Block
5 Axis engraving
Machining of scanned data
•Can be used with models in STLformat
Turbine blades
Sand casting
5 Axis Machining from solid
• Trend to machine complete from block– Shorter product life
cycles– Shorter development
lead times– Smaller production
runs• Replaces castings or
forgings
5 Axis simulation and verification
4-axis machining• Job rotates around the
X axis with linear, spiral or circular machining strategies along Y and Z axes.