
Set the chuck carriage plate stop
so
that
the valve face
will
just
reach the right edge of the grinding wheel
but
never
go
beyond. Dress the grinding wheel
to
clean up.
(SEE INSTRUCTIONS
FOR
DRESSING). Advance grind-
ing wheel towards the valve until wheel
just
touches.
Set micrometer
thimble
at zero. Begin grinding at
left
side
of
wheel, moving valve slowlyand steadily, rightand
left,
across the wheel.
DO
NOT ALLOW VALVE
AT
ANYTIME
TO
PASS
BEYOND
EITHER
EDGE
OF
THE GRINDING WHEEL WHILE GRIND-
ING. Take
light
cuts
by
feeding
the
wheel up
to
the valve
about
.001"-.002"
at a time. Remove
just
enough material
to
make a clean smooth face. When valve face
is
trued,
advance
to
right
until
top
edge of valve is flush with right
edge
of
grinding wheel. Pause a second, then back grinding
wheel away from valve, NOT VALVE
AWAY
FROM
WHEEL.
Keep valves in numbered rack to make sure you return them
to
their
own guides.
On
large diameter and hard faced valves,
it
may be neces-
sary
to
make a finish dress
of
the grinding wheel
for
a finish
grind.
Do
not
remove
the
valve
from
the
chuck.
Position the
dressing tool between valve and wheel
so
that
a complete
traverse
of
the grinding wheel can be made
without
contact
of
valve
to
grinding wheel. Again,
as
noted in dressing in-
structions,
for
hard faced valves, use the softergrade wheel
(Cat. No. 177).
Removable
Coolant
Tank
When
the
coolant becomes
dirty
it
must
be
cleaned out.
Soluble oil should
be
replaced. No.
250
Sioux grinding oil
may
be
reused.
'
TO
ADJUST
DRAG
ON
CARRIAGE PLATE:
Loosen or tighten the round
nut
located behind carriage
shifter
lever.
The
Sioux
Quick
Acting Roller
Chuck
The rollers automatically bring valve stem back against
the aligner,
thus
assuring a perfect alignment. They float
and roll, thereby changing position on every valve chucked;
this insures long life. The floating aligner
with
its inverted
center, alignsthe valve and also serves
as
astop, holdingthe
valve stem rigidly centered in the chuck. It is adjustable
for
valve stems of
different
lengths. Chuck the valve on the best
part of stem
just
above the worn surface.
Easy
to
clean-
The
sleeve on lever chuck
turns
com-
pletely
off
for cleaning. The snap ring on rear
of
hand chuck
sleeve jumps
off
when chuck
is
opened to maximum capac-
ity and additional
turn.
Replace sleeve completely and the
ring will snap in place. When replacing chuck sleeve put a
few drops of oil on the thread and bearings.
Accuracy
is
the principal feature in
the
manufacture
of
the
SIOUX
ROLLER CHUCK. The 956, 957 and
958
chucks
are tested within one thousandths of an inch.
Very few valve stems are perfectly
straight
and round;
therefore,
do
not
expect
to
test
the
accuracy
of
your
machine
by
grinding and then rechucking valve,
as
this
method of testing
is
not practical.
Note
Good
housekeeping
is
essential to keep any precision tool
in condition.
Use
the rubber shields (No. 631B) when grind-
ing or dressing
to
keep
grit
and coolant out of chuck. The
chuck
on
your machine has been factory adjusted
to
grind
valves within
.001"
T.I.R. concentrically. Keep
it
that
way.
Important!
Read
Carefully
GRINDING VALVES: Chuck the valve on the best part of
the stem
just
above the worn surface,
with
end
of
stem
resting solidly against floating aligner.
Begin grindingon
left
hand side
of
wheel face,
Grind
slowly
and move the valve slowly and steadily
forth
and back
on
wheel. Large valves grind
much
slower
than
small ones.
Take light
cuts
by
feeding the wheel
up
to
the valve a
little
at
a time. When
the
valve face
is
trued up, advance
to
the
right until the topedge of valve
is
flush
with
right hand edge
of wheel.
Stopa second ortwo, then back grinding wheel away from
valve. This will give a very fine finish.
No. 176 Grinding Wheel
is
recommended
for
general
grinding applications.
No.
177 Grinding Wheel
for
Aircraft
and Stellite Valves.
No. 81 Right End
Attachment
Grinding Wheel.
Dressing
Wheel
Take light cuts and move diamond steadily across wheel.
Whenever you fail
to
get a good finish on valves,
it
is most
likely the wheel needs dressing, oryou are feeding the valve
over the wheel too fast.
For faster grinding
on
hard valves, move the diamond
across the wheel faster than usual and dress the wheel
rough and sharp.
#1715-A
Heavy Duty Diamond is used
for
dressi
ng
the
right hand grinding wheel and the
#681
diamond
is
used
to
dress the
left
hand grinding wheel.
Interference
Angle
Grinding
For
better
valve jobs the 45° valves can be refaced to 44°
and the 30° valves
to
29
degrees, while the seats are
re
-
finished
to
the original
45
or
30
degrees. This assures
compression-tight, fully-seated valves; and
the
valve
life
and efficiency are greatly increased.
5