Dressing

Why Dressing
Pushing
Free penetrating
Dressed Blades Versus
Non Dressed Blades
High loads
Low diamond
exposure
Low machinability
High diamond
exposure
High machinability
Dressing
Dressing =
• Exposing
diamonds and releasing
partially embedded diamonds
Diamonds not exposed
•
Diamonds exposed after
dressing
Dressing
• Improving Concentricity of
blade edge to spindle rotation
Dressing
• Shaping the edge geometry:
- Flat edge
Flat edge
- Special geometry:
(-V-, Others)
-V- edge
Angled cut
Dressing Methods
• Electro polishing - nickel blades
Power supply
Etching solution
Blades
Dressing Methods
Cont.
• Electro polishing - nickel blades
Nickel blade
17mic. Grit - 330x / 1000x
after Electropolishing
Nickel blade
17mic. Grit - 100x
after Electropolishing
Nickel blade
17mic. Grit - 100x
After fine grinding
with a Si. Ca. wheel
Dressing Methods
• Cylindrical grinding:
Blade
Silicon Carbide
wheel
Dressing Methods
Cont.
• Cylindrical grinding:
Sil. Car. Grinding wheel
Blade
Flange
Arbor
Dressing Methods
Profile Grinding
Sil. Car. Grinding wheel
Blade
Dressing / Grinding Machine
Dressing / Grinding Machine
Dicing Dressing Media's
• Silicon Carbide - 320 / 600 / 800 mesh
• Silicon
• Others - Glass, Ceramic
• Diamond plates (For resin single & gang ass.)
Dressing Resinoid Blades
• Not needed in most cases
- Self re-sharpening blade
High
temperatures
Blade wear
Resin
Diamond
Dressing Resinoid Blades
• Lapping to open the blade side surfaces:
For applications requiring very straight / perpendicular cuts
Carriers
Double plate
Lapping
Machine
Blades
Top plate
Bottom plate
Dressing Resinoid Blades
Cont.
Example of a thick PZT application:
15.5mm cut depth
Dressing Metal Bond Blades
Hard and
sharp edges
Hard Nickel
Or metal sintered
Diamond (Blocky)
Dressing Metal Bond Blades
• Dressing with dressing media’s on the saws:
Dressing media
General dressing methods on the saw
• Cleaning powder residue to expose the
diamonds
• Machining off blade binder to expose
diamonds
Diamonds not exposed
Diamonds exposed after
dressing
General dressing methods on the saw
Cont.
• Flattening the blade edge
Before
- Lower the spindle RPM
- Use multiple shallow cuts
- Use slow feed rates
After
On Line Dressing
After each cut the blades is passing
a dressing media.
Substrate
Feed
Sil. Carbide or Al. Oxide
Dressing Stick.
Re - Dressing
During the Dicing Process
Powder residue
from the dicing
Blade edge
Dressing on the dressing station
Nickel / Diamond
Electroforming
17, 30 & 50 mic. grit
Silicon Carbide
600 mesh
Chuck
Dressing station
Dress station using a Nickel / Diamond media
• Designed only for dressing resinoid blades
• Should be used in a dicing mode not a
chop mode
Dress station using a nickel /diamond media
Dressing media
Nickel & Diamonds
Chopping mode
Z movement Only
Resinoid
Single diamonds in contact
with the blade edge
Binder - Nickel
Blade edge with a copy
of the diamonds geometry
Simulating the Chop mode
Metal file
Chop mode
Shaping mode
Dress station using a nickel /diamond media
Z – Copping mode –
Wrong process
Resinoid
Dressing media
Nickel & Diamonds
Edge defects
due
to high loading
Dress station using a nickel /diamond media
Stationary Z
Resinoid
Wear of blade edge
Resinoid
Y - Movement 0.005- 0.015 mm
Dress station using a nickel / diamond media
Cont.
Profile images of in Line Dressing
Resin - 56 mm O.D. - P/N 00777-C045-020-QUP
-WBefore
After
Dressing media P/N-00776-65D0-051-3X3 – 30mic grit
· Spindle Speed – 18 Krpm
· Feed rated – 5mm/sec
· Cut depth – 0.015 mm on each pass
No. of cuts to achieve a flat blade edge – 5x
·
Dressing station with nickel / diamond media
Cont.
Profile images of in Line Dressing
Resin – 4.6” O.D. - P/N 00777-6045-020-QUP
-W-
Before
After
Dressing media P/N-00776-65D0-051-3X3 – 30mic grit
· Spindle Speed – 8 Krpm
· Feed rated – 5mm/sec
· Cut depth – 0.015 mm on each pass
No. of cuts to achieve a flat blade edge – 5x
·
Dressing station with nickel /diamond media
Dressing a metal bond blade on a
nickel / diamond dressing media:
Nickel or Metal sintered
Blade binder
Diamonds remaining
in contact
with diamonds
Nickel / diamond dressing
block
Damaged diamonds
Dress station using a Silicon Carbide media
• Designed for light / moderate dressing
• Used similar to standard dressing media
which is mounted on the chuck
• To clean powder residue on metal or resin
type blades
• Can be used for flattening blades edges,
mainly resinoid - (Slower mode)