FOREWORD The horizontal milling machine (and later the vertical miller) evolved from the lathe about 100 years ago, when cutting tools were mounted on the spindle and rotated. As cutter-making techniques developed multi-toothed cutters followed the early simple tools In due course grinding machines which had one cutting point only. were needed for the sharpening of the cutting edges, which needed greater accuracy than a workman could achieve by holding the tool in his hands. Artificial abrasives appeared, with their better endurance of wheel form, and displaced the soft yellow sandstones previously used, used, making their own contribution to improved cutters. The tool-manufacturing plants gradually took into common use high-production machines of great accuracy, some of them single purpose machines to do only one operation through their entire life. Maintenance departments, content with lower outputs, acquired grinders of greater versatility, but no machine appeared cheap enough and small enough for the needs of model engineers* Milling in the lathe has been practised now for generations by model makers in their home hobby workshops, Making good use of the milling process was long held back by the limitations of lathes, by the absence of an adequate milling machine, and by the lack of In 1968 the introduction of the cutter sharpening facilities, Dore-Westbury vertical miller provided a machine with a very wide range of spindle speeds and generous table size and movements, at a low cost, but the cutter sharpening problem still remained. Fortunately Professor D. H. Chaddock, a highly gifted and experienced professional engineer, and himself a model engineer of great distincti distinction on too, acquired acquired one of the the first first sets of Dore-W Dore-Westbu estbury ry machine machine castings, castings, and soon devoted devoted his talents talents to the sharpening sharpening problem. The result was the "Quorn" grinder. Primarily designed for sharpening the sizes and types of milling cutter most used by model model engineers, engineers, the machine machine can also be used, without without adaptation adaptation, , for sharpening a wide range of other tools such as lathe, shaper and pla plane ner r t too ools ls, , ta taps ps, , re ream amer ers, s, tw twis ist t an and d ce cent ntre re dr dril ills ls, , With Wi th so some me ingenuity it can be used to produce special purpose cutters, or modify standard ones as well as more exotic tasks such as thread or cam forming in hardened materials, For home workshop use, for which it was was intend intended, ed, it is is complete completely ly succes successful, sful, even in nonnonThe thousands who have seen it being demonstrated at expert hands. the "Model Engineer" Exhibitions over several years will need no persuasion on this. The present instructional handbook explains in simple and clear terms just how to prepare the machine, and how to use it, while Professor Chaddock's excellent photographs make the words almost superfluous. Model engineers all the world over should be grateful to him for giving them the means to easily perform what has up to now been one of the most difficult tasks facing the operator of a home workshop.
Sheffield 1975
Arnold
Throp
Page 2
WHEEL
DRESSING
- CUP
OR
FACE
WHEEL
WHEEL
Axis parallel to base. Check by contacting back and front of wheel with diamond at approx. centre height. Rotation downwards at front.
HEAD
TOOTH
REST
Not used.
FRONT
BAR
Free. cut, not more than l/4 thou, per pass, given by micrometer, Clamped to front bar,
WORK HEAD BASE
Retracted to work head.
ROCKING
LEVER
TILTING
BRACKET
ROTATING TOOL
BASE
HOLDER
METHOD OF OPERATION
allow
free
oscillation
Set 15º anti-clockwise. Diamond must always trail, N.B. face, wheel rotation,
of
never
Set zero. Any
convenient
holder
to
suit
diamond,
Oscillate work head with diamond slowly across face of wheel, Apply cut by Protect machine front bar micrometer. with old newspaper or kitchen tissue and wipe down thoroughly afterwards.
Page 3 WHEEL
DRESSING -
DISC
OR
PLAIN
WHEELHEAD
WHEEL
Axis parallel to base. Set height so that diamond trails wheel by approx.
Page 2
WHEEL
DRESSING
- CUP
OR
FACE
WHEEL
WHEEL
Axis parallel to base. Check by contacting back and front of wheel with diamond at approx. centre height. Rotation downwards at front.
HEAD
TOOTH
REST
Not used.
FRONT
BAR
Free. cut, not more than l/4 thou, per pass, given by micrometer, Clamped to front bar,
WORK HEAD BASE
Retracted to work head.
ROCKING
LEVER
TILTING
BRACKET
ROTATING TOOL
BASE
HOLDER
METHOD OF OPERATION
allow
free
oscillation
Set 15º anti-clockwise. Diamond must always trail, N.B. face, wheel rotation,
of
never
Set zero. Any
convenient
holder
to
suit
diamond,
Oscillate work head with diamond slowly across face of wheel, Apply cut by Protect machine front bar micrometer. with old newspaper or kitchen tissue and wipe down thoroughly afterwards.
Page 3 WHEEL
DRESSING -
DISC
OR
PLAIN
WHEELHEAD
WHEEL
Axis parallel to base. Set height so that diamond trails wheel by approx.
Page 2
WHEEL
DRESSING
- CUP
OR
FACE
WHEEL
WHEEL
Axis parallel to base. Check by contacting back and front of wheel with diamond at approx. centre height. Rotation downwards at front.
HEAD
TOOTH
REST
Not used.
FRONT
BAR
Free. cut, not more than l/4 thou, per pass, given by micrometer, Clamped to front bar,
WORK HEAD BASE
Retracted to work head.
ROCKING
LEVER
TILTING
BRACKET
ROTATING TOOL
allow
free
oscillation
Set 15º anti-clockwise. Diamond must always trail, N.B. face, wheel rotation,
BASE
of
never
Set zero. Any
HOLDER
convenient
holder
to
suit
diamond,
Oscillate work head with diamond slowly across face of wheel, Apply cut by Protect machine front bar micrometer. with old newspaper or kitchen tissue and wipe down thoroughly afterwards.
METHOD OF OPERATION
Page 3 WHEEL
DRESSING -
DISC
OR
WHEEL
PLAIN
Axis parallel to base. Set height so that diamond trails wheel by approx. 15º rotation downwards at front.
WHEELHEAD
TOOTH
REST
FRONT
BAR
WORK HEAD
Not used. Locked. BASE
Micrometer
not
used.
Free to slide on front bar.
ROCKING
LEVER
Set to bring diamond up to wheel, Cut, not more than l/4 thou, per pass. applied by backing off micrometer stop screw,
TILTING
BRACKET
Set zero.
ROTATING TOOL
BASE
HOLDER
METHOD OF OPERATION
Set zero. Any
convenient
holder
to
suit
Slide work-head with diamond slowly back and forth along front bar keeping rocking lever stop screw firmly in contact with rear bar, Apply cut by backing off micrometer Protect machine with old stop screw, newspaper or kitchen tissue and wipe down thoroughly afterwards.
Page 4
WHEEL
DRESSING
-
ANGLE
diamond.
WHEEL
Page 3 WHEEL
DRESSING -
DISC
OR
WHEEL
PLAIN
Axis parallel to base. Set height so that diamond trails wheel by approx. 15º rotation downwards at front.
WHEELHEAD
TOOTH
REST
FRONT
BAR
WORK HEAD
Not used. Locked. BASE
Micrometer
not
used.
Free to slide on front bar.
ROCKING
LEVER
Set to bring diamond up to wheel, Cut, not more than l/4 thou, per pass. applied by backing off micrometer stop screw,
TILTING
BRACKET
Set zero.
ROTATING TOOL
BASE
HOLDER
METHOD OF OPERATION
Set zero. Any
convenient
holder
to
suit
Slide work-head with diamond slowly back and forth along front bar keeping rocking lever stop screw firmly in contact with rear bar, Apply cut by backing off micrometer Protect machine with old stop screw, newspaper or kitchen tissue and wipe down thoroughly afterwards.
Page 4
WHEEL
DRESSING
-
ANGLE
diamond.
WHEEL
Page 4
WHEEL
WHEELHEAD
DRESSING
-
ANGLE
WHEEL
Set at required angle with bevel gauge or protractor. Diamond at exact centre height of wheel. Rotation
downwards at front. TOOTH REST
FRONT BAR
WORK HEAD BASE ROCKING LEVER TILTING BRACKET
Not used. Free. cut, not more than l/4 thou, per pass, given by micrometer. Clamped to front bar. Retracted to allow free oscillation of work head, Set 15º anti-clockwise. N.B. Diamond must always
wheel ROTATING BASE TOOL HOLDER METHOD OF
OPERATION
trail,
never
face,
rotation.
Set zero. Any convenient holder to suit diamond. Oscillate work head with diamond slowly across face of wheel applying cut by backing off front bar micro meter screw. L.H. side of wheel is most conveniently dressed by the method given on page 2, setting the wheel head to an appropriate angle. Protect machine with old newspaper or kitchen tissue and wipe down
thoroughly
afterwards.
WHEEL
WHEEL
DRESSING -
RADIUS
DRESSING
Axis parallel to base. Diamond at exact centre height of wheel. Rotation downwards at front.
HEAD
TOOTH
REST
Not
FRONT
BAR
Use micrometer screw to bring diamond into exact coincidence with R.H. side or face of wheel to be Back off dressed and then set thimble to zero, before taking cut.
WORK
HEAD
BASE
used,
Clamped
to
front
bar,
ROCKING
LEVER
Use micrometer stop screw to bring diamond into exact coincidence with L.H. face or periphery of wheel and lock,
TILTING
BRACKET
Set
ROTATING TOOL
BASE
HOLDER
METHOD OF OPERATION
zero.
Free,
Set
stops
to
limit
travel
in
either
direction,
Tip of diamond Any convenient holder to suit diamond, must be aligned with axis of rotating base by means of a setting pin and distant from it by a distance See also page 17. equal to the radius to be ground, Oscillate rotating base between stops and gradually bring work head back to zero position as indicated by front bar micrometer thimble.
Page 6 TOOL
GRINDING
-
ZERO
SETTING
1.
Clamp tool in tool holder. of holder,
2.
Insert long setting pin in rotating
3.
Insert tool holder in tool
4.
Free bracket and spindle locks. Press base of tool firmly against face of setting pin and retighten both locks,
5.
Free the index ring,
6.
Remove the tool holder and the setting pin.. Replace the tool holder in any desired quadrant, setting it by means of the degree scale on the index plate and locking it when set.
TOOL
GRINDING
Set screws must be below surface
holder
base.
bracket.
set to zero and relock.
-
SIDE
RAKE
AND
CLEARANCE
TOOL
WHEELHEAD
TOOTH
REST
FRONT
BAR
WORK
HEAD
GRINDING
-
SIDE
Axis parallel edge. Not
to
base,
Clamped
Cut to
applied front
LEVER
Set to limit travel shoulder present on
TILTING
BRACKET
Set
TOOL
BASE
HOLDER
METHOD
OF
OPERATION
CLEARANCE
Rotation
towards
cutting
by
micrometer,
bar.
ROCKING
ROTATING
AND
used.
Free. BASE
RAKE
of work tool,
towards
wheel
if
zero.
Set to give side rake. lº back for parting tools, Oº for facing tools, half thread angle for screw cutting tools. Set to clearance angle. lº for parting tools, 5-7º for turning and facing tools. Reverse side of tool ground the same way by turning tool holder through 180° and measuring angles in second quadrant. Top and back rake ground by turning tool holder through 90° and measuring angles in first quadrant. Oscillate tool across face of wheel applying cut by backing off micrometer. All faces of the tool can be ground at a single setting,
TOOL
GRINDING
-
FRONT
RAKE
AND
CLEARANCE
WHEEL HEAD
TOOTH FRONT WORK
Axis parallel to base. towards cutting edge. Not used.
REST BAR
HEAD
Rotation
Free, BASE
Cut
applied
by
micrometer.
Clamped to front bar.,
ROCKING
LEVER
Retracted to allow free movement work head,
TILTING
BRACKET
Set to front clearance angle, usually 5 - 7º.
ROTATING
TOOL
Set to front clearance angle. for Oº for parting tools, 5-7º facing tools.
BASE
HOLDER
METIIOD
Set zero. Oscillate tool across face of wheel applying cut by backing off micrometer These operations can convenscrew. iently follow or precede those d e s c r i b e d on page 7 without disturbing the tool in its holder or re-setting it,
OF
OPERATION
Page TOOL
WHEELHEAD
GRINDING
Axis edge.
-
SCREW
parallel
to
CUTTING
base,
of
OR
FORM
Rotation
9
TOOL
against
cutting
Page TOOL
GRINDING
Axis
WHEELHEAD
-
SCREW
parallel
CUTTING
to
OR
FORM
base,
Rotation
by
micrometer.
9
TOOL
against
cutting
edge. TOOTH
REST
FRONT
BAR
WORK
HEAD
Not
used,
Free, BASE
Cut
Clamped
to
ROCKING
LEVER
Retracted,
TILTING
BRACKET
Set
ROTATING
TOOL
BASE
HOLDER
METHOD OF OPERATION
applied front
bar,
zero.
Set to give rake angle required, e.g. half thread If both sides ground angle for screw cutting tool, at same setting point will be symmetrical with axis of tool. Positive (clockwise when Set to clearance angle. grinding L.H.S., and negative (anti-clockwise) when grinding R.H.S. of tool. Oscillate tool across face by backing off micrometer
TOOL
GRINDING
-
RADIUSING
of wheel screw.
applying
cut
TOOL
GRINDING
-
RADIUSING
Axis parallel to base. downwards at front.
WHEELHEAD
TOOTH REST
Not used.
FRONT BAR
Free.
WORK HEAD BASE ROCKING LEVER
Rotation
Cut applied by micrometer.
Clamped to front bar. Set to centralise work on face of wheel.
TILTING BRACKET Set to front clearance angle. ROTATING BASE
Free.
TOOL HOLDER
For compound angles set to Set zero. difference between front and side clearance angles. e.g. 5º front clearance, 7" side clearance, set tool holder to 7 - 5= 2º positive (clockwise). If the work is to make more than 90° rotation it may be necessary to retract the tool holder bracket on its spigot and extend the tool accordingly and a small wheel to gain necessary clearance.
METHOD OF OPERATION
Set stops to required angles.
The tangent faces of the tool, which should have been ground previously, must be aligned at the required radius with the axis of the rotating base, using either the long setting pin or, more conveniently, the setting micrometer. The work is rocked between stops and advanced towards the wheel by the front bar micrometer screw until the radius blends with the tangent faces of the tool.
Page CUTTER
GRINDING
-
TOOTH
REST
SETTING
I
A
Tooth Tooth Rest DISC WHEEL
CUP WHEEL
11
Page CUTTER
GRINDING
-
TOOTH
REST
11
SETTING
I
A
Tooth Tooth Rest DISC WHEEL
CUP WHEEL
Tooth
R e s t
ZERO SETTING - DISC WHEEL
D i s t a n c e t o s e t t h e c e n t r e of t h e wheel ABOVE t h e c u t t e r centre ( d i s c wh ee l) t o n e a r e s t 0.005 i n . Wheel Diameter
Clearance angle 6 deg.
7 deg.
0.090 0.100 0.110 0.120
0.105 0.120 0.130
0 120 0.135 0.150 0.165 0.180 0.195 0.210 0.225 0.240
0.145 0.155 0.165 0.175
BELOW the cutter centre
( cu p w he el ) t o n e a r e s t 0,001 i n . Clearance angle
Cutter
5 deg.
0.145 0.155 0.170 0.185 0.195 0.210
Distance t o s e t t o o t h rest
.
Diameter
1/4" 3/8" 1/2" 5/8" 3/4"
5 deg.
6 deg.
7 deg.
0.011 0.015 0.022 0.028 0.033 0.037 0.044
0.013 0.020 0.026 0.033 0.039 0.046 0.052
0.015 0.022 0.030 0.037 0.045 0.052 0.060
Page 12 CUTTER
GRINDING
-
SHELL,
SLAB
AND
END
MILLS
Page 12 CUTTER
GRINDING
-
SHELL,
(DISC
WHEELHEAD
SLAB
AND
END
MILLS
WHEEL)
Axis parallel to base. Height set according to page 11. Rotation downwards at front, N.B. This is important to hold work against tooth rest.
TOOTHREST
Height set according to page 11 may be angled to suit R.H. or L.H. cutter.
FRONT BAR
Free when setting.
WORK HEAD BASE
Locked when grinding.
Clamped to front bar,,
ROCKING LEVER
Set to bring work into contact with wheel. cut applied by backing off micrometer stop screw.
TILTING BRACKET
Set zero.
ROTATING BASE
Set zero.
TOOL HOLDER
Mandrel to suit cutter to be ground.
Cutter may slide and rotate on a dead mandrel clamped in tool holder or
be fastened to live mandrel sliding free in tool holder. Tool holder may be set away from or towards wheel to
accommodate work/wheels of different diameters. METHOD OF OPERATION
After locking all settings slide cutter back and forth firmly in contact with tooth rest. Grind every tooth in turn at same setting. Free front bar and back off
rocking lever stop screw to increase cut.
CUTTER
GRINDING
-
SHELL,
(CUP
WHEELHEAD
SLAB
AND
END
MILLS
WHEEL)
Axis at right angles to base.
Height as convenient.
Rotation downwards at front, N.B. This is important to hold work against tooth rest. TOOTH REST
Height set according to page 11. May be angled to suit R.H. or L.H. cutter.
FRONT BAR
Free when setting,
WORK HEAD BASE
Locked when grinding.
Clamped to front bar.
ROCKING LEVER
Set to bring work into contact with wheel,
TILTING BRACKET
Set zero.
ROTATING BASE
Set zero.
TOOL HOLDER
cut applied by backing off micrometer stop screw.
Mandrel to suit cutter. Cutter may slide and rotate on dead mandrel clamped in tool holder or be fastened
to live mandrel sliding free in tool holder.
Tool
holder may be set towards or away from wheel to
accommodate work/wheels of different diameters. METHOD OF OPERATION
After locking all settings slide cutter back and forth firmly in contact with tooth rest. Grind every tooth in turn at same setting. Free front bar and apply next cut by backing off rocking lever stop screw. Re-lock
before grinding. Page 13A
Page 13A CUTTER
GRINDING
-
SHELL,
(CUP
Close-up of 5/8" by
SLAB
AND
END
MILLS
WHEEL)
2" end mill set for grinding by cup wheel,
Page 14
CUTTER
GRINDING
-
DOVETAIL
AND
ANGLE
MILLS
Page 14
CUTTER
WHEEL HEAD
TOOTH REST
FRONT BAR WORK HEAD BASE
GRINDING
-
DOVETAIL
AND
ANGLE
MILLS
Axis parallel to base. Height set according to page 11, Rotation, if index plate is used up against tooth face. May be used for large cutter - see page 12. For small or fine tooth cutter not used,
Locked. Free to slide on front bar.
ROCKING LEVER
Set to bring work into contact with wheel, cut applied by backing off micrometer stop screw.
TILTING BRACKET
Set zero.
ROTATING BASE
Set to required cutter angle.
TOOL HOLDER
METHOD OF OPERATION
As for page 12 if tooth rest is being used. Collet chuck and index ring for small or fine tooth cutters. Set one tooth vertical or horizontal with long setting Set index ring to zero. For sub pin (see page 25). For other numbers multiples of 12 use index holes. use degree scale. After locking all settings except work head base, slide entire workhead along front bar, keeping rocking lever Index and stop screw firmly in contact with rear bar. grind every tooth in turn. Apply next cut by backing off stop screw.
Axis parallel to base. Rotation upwards towards cutting edge.
WHEELHEAD
Not used.
TOOTH REST FRONT BAR
Free.
WORK HEAD BASE
Cut applied by micrometer screw.
Clamped to front bar.
ROCKING LEVER
Set to limit cut towards centre of cutter.
TILTING BRACKET
Set to clearance angle.
ROTATING BASE
Set zero or minus lº to give heel relief.
TOOL HOLDER
Set one Collet chuck and index ring. tooth vertical or horizontal with long Set index setting pin (see page 25), Index either with holes, ring to zero. for sub-multiples of 12, or degree scale.
METHOD OF OPERATION
Advance the work towards the wheel under control of the front bar micrometer Grind the tooth by rocking the screw. work head up to the stop screw and back Swing clear and index and grind again. each successive tooth in turn. Apply the next cut, if required, by backing off the front bar micrometer screw. Secondary clearance, if required, is obtained by increasing the angle of the tilting bracket and re-grinding.
Page 16 CUTTER
WHEELHEAD
TOOTH REST
GRINDING
-
SIDE
AND
FACE
CUTTERS
Height to give clearance Axis parallel to base. between teeth. Rotation against tooth rest. Set to bring tooth horizontal.
May be used inverted
Page 16 CUTTER
WHEELHEAD
GRINDING
-
SIDE
AND
FACE
Height to give clearance Axis parallel to base. between teeth. Rotation against tooth rest.
TOOTH REST
Set to bring tooth horizontal. as shown,
FRONT BAR
Free.
WORK HEAD BASE
CUTTERS
May be used inverted
Cut applied by micrometer
screw.
Clamped to front bar.
ROCKING LEVER
Set to limit cut towards centre of cutter.
TILTING BRACKET
Set to required clearance angle.
ROTATING BASE
Set zero or minus lº, to give heel relief.
TOOL HOLDER
METHOD OF OPERATION
Dead mandrel Mandrel to suit cutter to be ground. with shoulder or live mandrel with stop collar. Tool holder bracket may be swung away from or towards wheel to accommodate larger or smaller cutters. Advance work towards wheel under control of front bar micrometer screw. Keep tooth firmly in contact with tooth rest and grind by rocking across face of wheel. Swing clear and grind each tooth in turn. Apply next cut, if required, by front bar micrometer screw. Secondary clearance by increasing angle of tilting bracket and re-grinding.
CUTTER
GRINDING
-
BALL
NOSE
CUTTERS
Before a ball nose or semi-spherical cutter can be ground, the axes of the rotating base and the tool holder must be brought into alignment. Insert the long setting pin into the hole in the rotating base and a short setting pin in a suitable collet in the indexing mandrel. Free the tool holder bracket and the index ring and bring the two faces of the setting pins firmly together., Lock the tool holder bracket. N.B. This setting must not be disturbed until grinding is finished. As a check retract the long setting pin, turn it and the short pin through 180º and re-engage 0 There should be no clearance or interference, Set the cutter to be ground in suitable collet chuck with its nose projecting beyond the face of the long setting pin by an amount equal to the radius plus a grinding allowance. This is most conveniently done with a setting micrometer. Set one tooth of the cutter vertical against the face of the partially retracted long setting pin and the index ring to zero. Fully retract the setting pin and index through 90° before grinding.
Page 18
BALL
WHEEL HEAD
NOSE
CUTTERS
Rotation Cup wheel. Axis parallel to base. wards at front. Height unimportant.
down-
Page 18
BALL
WHEEL HEAD
TOOTH
REST
FRONT
BAR
WORK HEAD BASE
NOSE
CUTTERS
Rotation Cup wheel. Axis parallel to base. wards at front. Height unimportant. Not used. Free,
Cut
applied
by
micrometer
screw.
Clamped to front bar,
ROCKING
LEVER
Set to centralise work on face of wheel.
TILTING
BRACKET
Set to give clearance angle required.
ROTATING TOOL
BASE
HOLDER
MANDREL OF OPERATION
METHOD
down-
Free.
Set stops to Oº and 90°.
Aligned with rotating base as per page 17. Collet to suit cutter and index ring. Rotating base is swung between stops and advanced towards wheel by front bar micrometer screw. cut must cease when radius blends with side of cutter. Secondary clearance by resetting tilting bracket. One tooth usually ground past centre to avoid leaving a pip on the work. End faces of spirally fluted cutters to be ground square before radiussing,
CORNER
RADIUSING
CORNER
RADIUSING
WHEEL HEAD
Cup wheel. Axis parallel to base. Rotation against tooth rest.
TOOTH REST
Set at centre height. May be used inverted. Narrow point desirable.
FRONT BAR
Free.
WORK HEAD BASE
Cut applied by micrometer screw.
Clamped to front bar.
ROCKING
LEVER
Set to centralise work on face of wheel,
TILTING
BRACKET
Set to clearance angle required.,
ROTATING
BASE
TOOL HOLDER
Free.
Set stops to Oº and 90°,
Offset to bring corner of cutter into correct relationship with axis of rotating base. Use setting pin or micrometer. To suit cutter.
MANDREL METHOD OF OPERATION
Index ring not used,
Swing rotating base between stops advancing work towards wheel by micrometer screw. Cut must cease when radius blends with side and face of cutter. Secondary clearance by resetting tilting bracket.
Page SMALL
WHEEL
HEAD
END
MILLS
AND
SLOT
20
DRILLS
Narrow disc wheel. Axis inclined to spiral angle. Rotation outwards at bottom. Depth of cut by height adjustment.
Page SMALL
MILLS
AND
SLOT
DRILLS
HEAD
Narrow disc wheel. Axis inclined to spiral angle. Rotation outwards at bottom. Depth of cut by height adjustment.
TOOTH
REST
Not used.
FRONT
BAR
WHEEL
WORK
HEAD
Locked. BASE
ROCKING
LEVER
TILTING
BRACKET
ROTATING TOOL
END
20
BASE
HOLDER
MANDREL OF OPERATION
METHOD
Clamped
to
front
bar,
Not used. Set zero. Set zero. Spiralling head with traversing mandrel hob, Set stop to length of flute.
and
guide
, To suit cutter and guide hob. Flute formed by spiralling mandrel in and out. Retract and engage second thread to form second Back-off as page 12 using hob for guidance, flute. End teeth formed as pages 15 and 18 using hob and stop for indexing. Page 21
Page 21 GRINDING
THREAD
WHEEL
HEAD
TOOTH
REST
FRONT
BAR
WORK
HEAD
Disc wheel dressed to thread angle - see page 4. Axis parallel to base, Rotation upwards at front. Not used. Free
BASE
when
Clamped
to
ROCKING
LEVER
Depth
TILTING
BRACKET
Set
to
Set
zero.
ROTATING TOOL
BASE
HOLDER
MANDREL
OF OPERATION
METHOD
GULLETTING
setting,
of
front
cut
locked
grinding,
bar,
controlled
helical
when
angle
by
of
stop
screw.
thread.
Spiralling head with traversing mandrel Set stop to length of thread, hob, To
suit
work
and
guide
and
guide
hob,
Advance
work slowly against direction of rotation of may require re-dressing more than once wheel. Wheel before full depth of thread can be formed, e.g. from solid,
FINE
TOOTH
SAWS
AND
FORM
TOOTH
CUTTERS
GULLETTING
WHEEL HEAD
TOOTH REST BAR
FRONT
WORK
HEAD BASE
FINE
TOOTH
SAWS
AND
FORM
Not
used.
Locked. Free to slide on front bar.
LEVER
Free to slide on rear bar,
TILTISG
BRACKET
Set zero.
TOOL
BASE
HOLDER
Set zero. Either but MUST have division plate with same number of divisions as cutter to be ground. To suit cutter and division plate.
MANDREL
METHOD
CUTTERS
Disc wheel dressed to included angle, see page 4. for saws. Narrow saucer wheel for form and gear Rotation tooth cutters. Axis parallel to base. outwards at bottom.
ROCKING
ROTATING
TOOTH
OF
OPERATION
Face of cutter to be ground is set radial (form and gear cutters), hooked or negative rake (saws), with Cut applied by inchi setting pin and straight edge. division plate and taken by sliding workhead along front bar, keeping rocking lever stop firmly in Depth of gullet in saws contact with rear bar. controlled by wheelhead height adjustment. Page
REAMERS
AND
LONG
CUTTERS
23
Page
REAMERS
WHEEL
HEAD
TOOTH
REST
FRONT
BAR
WORK
HEAD
AND
LONG
CUTTERS
May be parallel to base, disc: wheel (see page 12), or at right angles, cup wheel (see page 13 ). Rotation downwards towards tooth rest, Height set page 11).
to
give
clearance
BASE
required,
(see
Free to slide on front bar.
LEVER
Free to slide on rear bar.
TILTING
BRACKET
Set
TOOL
angle
Locked,
ROCKING
ROTATING
23
BASE
HOLDER
zero,
Set zero for parallel reamers. Set to half included angle for taper reamers and cutters, N.B. It is advisable not to rely upon the degree scale for accurate setting but to take a trial cut or set with a test bar and dial gauge. Long bar bed with as headstock. with
or
female
and
either
tool
holder
MANDREL
Any
METHOD OF OPERATION
slid along front bar keeping rocking lever Depth of cut stop firmly in contact with rear bar. by backing off rocking lever stop screw and re-locking. Workhead
male
tailstock
centres.
TAP
WHEEL
REST
FRONT
BAR
WORK
Narrow disc w h e e l radius dressed, see page 5, Rotation towards Axis at r i g h t angles to base.
HEAD
TOOTH
HEAD
,
Not
Locked, BASE
Free
to
slide
along
front
to
slide
along
rear
LEVER
Free
TILTING
BRACKET
Set
zero.
Set
zero.
Long
bar
TOOL
work,
used.
ROCKING
ROTATING
SHARPENING
BASE
HOLDER
as
bed
with
bar, bar,
tailstock
and
either
tool
holder
headstock,
MANDREL
Any
with
male
or
METHOD OF OPERATION
Workhead slid along front bar keeping rocking lever Sides stop screw firmly in contact with rear bar,
of flute kept in finger pressure.
female
contact
centres.
with
grinding
PRELIMINARY
wheel
SETTING
by
PRELIMINARY
SETTING
Hold drill in true running collet chuck with minimum overhang. Free tool holder and mandrel locks and align lip of drill with setting pin.
zero.
Set index ring to Lock tool holder and mandrel. Retract setting pin. Free mandrel lock.
Page TWIST
DRILL
GRINDING
-
4
FACET
METHOD
Cup wheel, axis parallel to Rotation upwards at front.
WHEEL HEAD
TOOTH
REST
FRONT
BAR
WORK
HEAD
Not
base.
used.
Free. BASE
ROCKING
LEVER
TILTING
BRACKET
ROTATING
BASE
TOOL HOLDER and M ANDREL METHOD OF OPERATION
Clamped Set
to
front
bar.
clear.
Set to clearance required, 10º and 30º secondary clearance,, Set to complement normally 31°. See
page
25
for
of
half
setting
primary
point
DRILL
angle
instructions,
Swing workhead across face of wheel applying cut by means of front bar micrometer screw. Index l8Oº and grind second lip at same setting. Re-set tilting bracket to second clearance angle and grind until intersection of the two lands is exactly across the centre line of the drill.
Page
CENTRE
26
GRINDING
27
Page TWIST
DRILL
GRINDING
-
4
FACET
METHOD
Cup wheel, axis parallel to Rotation upwards at front.
WHEEL HEAD
TOOTH
REST
FRONT
BAR
WORK
HEAD
Not
base.
used.
Free. BASE
ROCKING
LEVER
TILTING
BRACKET
ROTATING
26
BASE
TOOL HOLDER and M ANDREL METHOD OF OPERATION
Clamped Set
to
front
bar.
clear.
Set to clearance required, 10º and 30º secondary clearance,, Set to complement normally 31°. See
page
25
for
of
half
setting
primary
point
angle
instructions,
Swing workhead across face of wheel applying cut by means of front bar micrometer screw. Index l8Oº and grind second lip at same setting. Re-set tilting bracket to second clearance angle and grind until intersection of the two lands is exactly across the centre line of the drill.
Page
CENTRE
WHEEL
TOOTH
HEAD
REST
DRILL
GRINDING
Small cup wheel. Axis downwards at rear. Not
used,,
parallel
to
base.
Rotation
27
Page
CENTRE
WHEEL
REST
FRONT
BAR
WORK
BEAD
Not
BASE
LEVER
TILTING
BRACKET
TOOL
BASE
HOLDER
M A N DR E
L
METHOD OF OPERATION
parallel
to
base.
Rotation
used,,
Locked.
ROCKING
ROTATING
GRINDING
Small cup wheel. Axis downwards at rear.
HEAD
TOOTH
DRILL
27
Clamped Not Set
to
front
bar.
used. zero.
Set 30°. Spiralling To
suit
head
drill
with
and
traversing
guide
mandrel
and
guide
hob.
hob.
Set drill so that point is clear of far side of wheel. between Apply feed by advancing hob guide pin. Rotate Form point stops to form and back-off conical lips. Reform flutes as page 22. as page 26.
Page 28
SAW
SHARPENING
Page 28
SAW
WHEEL HEAD
TOOTHREST
FRONT BAR WORK HEAD BASE
SHARPENING
Disc wheel, dressed to included angle, see page 4, Rotation downwards at front. Axis parallel to base. Not used. Free. Clamped to front bar.
ROCKINGLEVER
Set to limit depth of cut.
TILTING BRACKET
Set zero.
ROTATING BASE
Set to give required tooth angle, normal, hooked or negative.
TOOL HOLDER
Saw grinding attachment with spring detent.
MANDREL METHOD OF OPERATION
Clamped in tool holder, Engage detent in second saw tooth and grind first Lift rear tooth by rocking workhead to fixed stop. of saw blade and engage detent with third tooth, Grind second tooth etc. N.B. The last tooth cannot be ground this way and must either be finished freehand or omitted. All teeth of a band saw can however be ground in one operation,,