Logan 915 Instruction sheet
REVERSING
SWITCH
HEADSTOCK
•I
FIGURE
1-LOGAN
NO
.
920
FLOOR MODEL
11
" SWING QUICK CHANGE GEAR LATHE
2
.,
LOGAN
LATHES
The
cases
in
which
your
Logan
Quick
Change
Gear
Floor
Model
Lathe
is
delivered
contain
the
following:
l
Logan
Lathe
with
headstock.
tailstock.
and
carriage
mounted
on
the
lathe
bed
2-step V
type
motor
pulley
(screwed
to
base
of
lathe
crate)
Bag
tied
firmly to
lathe
bed
containing
l tool
post
tool
post
ring
l tool
post
screw
l tool
post
wedge
l tool
post
block
l tool
post
wrench
l
tailstock
wrench
2 60°
centers
l
Headstock
Adapter
Sleeve
l
knob
and
quill
Countershaft
assembly-floor
type
V Belt
(attached
to
countershaft)
Six
conductor
cable
(in
bag
attached
to
headstock)
Instruction
book
(inside
the
change
gear
guard)
Parts
List (inside
the
change
gear
guard)
Chip
pan
Set
of floor
legs
For
the
Bench
Model
Lathe
the
chip
pan
and
floor
legs
are
omitted
and
the
countershaft
assembly
will
be
the
bench
type
instead
of
the
floor
type.
Unpack
carefully
and
check
to
be
certain
that
you
have
removed
all
the
pieces.
After
removing
the
lathe
from
its
shipping
case,
clean
it
thoroughly
with
a stiff
brush
and
kerosene.
Then
cover
all
the
unpainted
surfaces
with
a film of
good
machine
oil to
prevent
rusting.
These
sur-
faces
should
be
covered
with
a film of oil
at
all
times
and
the
lathe
should
be
covered
with
canvas
when
not
in
use.
Setting
Up
the
Lathe
FLOOR MODEL.
Mount
the
lathe
on
the
chip
pan
and
the
floor
legs,
using
the
bolts
furnished,
and
attach
the
countershaft
assembly
to
the
rear
of
the
headstock
as
shown
in
Fig
.
2.
When
mo
unt
ing
t
he
l
athe
on
the
pan
and
legs,
notice
that
the
holes
in
the
pan
are
not
drilled
an
equal
distance
from
the
sides
of
the
pan
.
The
short
side
is
to
be
mounted
towards
the
back
of
the
lathe
to
keep
the
pan
from
interfering
with
the
motor.
Locate
the
lathe
on
a
solid
level
floor.
preferably
concrete
,
in
a
dry
well
lighted
location,
using
lag
screws
or
bolts
to
fasten
the
legs
to t
he
floor.
If
the
lathe
is
set
on
a con-
crete
floor,
mark
the
l
ocation
of
the
bolt
holes
and
drill
in
the
concrete
with
a
star
drill
setting
the
lag
screws
or
bolts
in
expansion
shields
or
in
melted
lead.
3
It
is
of
the
greatest
importance
that
the
lathe
be
level;
if
it
is
not. its
weight
will
cause
the
lathe
bed
to
be
twisted,
throwing
the
lathe
out
of true.
It
is
impossible
to
do
ac-
curate
work
on
a
lathe
that
is
not
level
and
the
lathe
will
be
damaged
beyond
repair.
When
the
lathe
is
in
position,
place
a
sensitive
machin-
ist's
level
on
top
of
the
lathe
bed
and
adjust
any
varia-
tion from
level
by
placing
thin
shims
under
the
feet.
Be
certain
the
lathe
is
level
across
the
ways
and
parallel
to
them,
both
at
the
headstock
and
tailstock
ends.
When
the
lathe
is
level
bolt
down
tightly
and
check
the
level-
ing
.
It
may
be
necessary
to
loosen
the
bolts
and add
more
shims
.
Remember
the
lathe
must
be
level
if it
is
to
perform
accurately.
BENCH MODEL.
Attach
the
countershaft
assembly
and
place
the
lathe
in
position
on
the
bench.
The
bench
for
the
lathe
should
be
31
to 33
inches
high
of
heavy
con-
struction
and
suitably
reinforced
for
steadiness
and
should
have
a
top
of
seasoned
wood
at
least
two
inches
thick.
We
suggest
that
the
top
either
be
doweled
or
that
4 or 5
steel
rods
with
end
nuts
be
run
crosswise
through
the
top
and
the
nuts
turned
tight.
pulling
the
boards
to-
gether.
Plane
the
bench
top
level
and
place
the
lathe
upon
it.
Mark
and
drill four
%-inch
holes
under
the
r.or-
responding
holes
in
the
legs
at
each
end
of
the
lathe.
Through
these
holes
place
four
machine
bolts
to
fasten
the
lathe
to
the
bench
and
to
aid
in
leveling.
Then
pro-
ceed
to
level
the
lathe
bed
with
shims
as
described
above
for
the
floor
model.
Mounting
the
Motor
The
Logan
Lathe
is
designed
to
be
powered
by
a 1750
RPM motor.
When
the
lathe
is
in
place
mount
the
motor
on
the
motor
bracket
beneath
the
countershaft.
Do
not
tighten
bolts
until
the
motor
position
has
been
adjusted.
To
adjust
the
motor
position,
align
motor
pulley
and
the
pulley
on
the
countershaft
by
moving
the
motor
until
the
two
are
in line.
Tighten
the
base
bolts,
but
do
not
place
the
belt
on
the
pulley
until
the
motor
wires
have
been
connected
and
the
motor
pulley
tested
for
direction
of rotation.
Connect
the
drum
revers
i
ng
switch
mounted
on
the
countershaft
with
the
motor
,
using
rubber
covered
6 con-
ductor
cable
in
accordance
with
the
wiring
diagram
pasted
on
the
inside
of
the
switch
cover.
Motors
furnished
by
Logan
have
a wiri
ng
diagram
packed
with
the
motor
to
assist
in
making
the
proper
connections.
Connect
the
motor
to
the
current
source.
The
motor
pulley
should
then
rotate
clockwise,
viewed
from
the
motor
pulley
end,
when
the
switch
is
in
the
forward
position.
Combined
switch
and
motor
wiring
diagrams
are
shown
on
the
last
page
of
this
booklet
for
use
with
the
motors
we
furnish.
We
recommend
the
use
of a
good
three
phase
motor
that
is
electrically
balanced
and
will
not
transmit
vibra
-
tion
through
the
belts
to
the
headstock,
causing
chatter.
Split
phase
motors
are
not
recommended
,
especially
where
fine
work
is
required.
Adiusting
the
Belts
The
belt
from
the
motor
to
the
countershaft
and
the
one
from
the
countershaft
to
the
lathe
are
easily
adjusted
for
tension
.
Neither
of
these
belts
should
be
too
tight.
the
tension
depending
on
the
load.
Excessive
belt
pressure
will
shorten
the
life of
the
belt,
place
a
strain
on
the
bearings
and
cause
a
loss
of
power
through
excessive
friction.
When
adjusted
for
normal
work
a
moderate
pressure
on
the
middle
of
either
belt
should
depress
it
about
l Y2
inches
.
The
motor
bracket
is
hinged
at
one
side
with
a
bolt
and
nut
adjustment
that
raises
or
lowers
it,
thereby
decreasing
or
increasing
the
tension
on
the
V belt.
The
V
belt
rides
in
a V
groove
of
the
two
step
motor
pulley
and
on
a flat
face
of
the
two
step
countershaft
pulley.
When
the
cone
pulley
guard
is
raised
,
the
countershaft
automatically
moves
toward
the
headstock,
thereby
releasing
the
tension
on
the
flat belt.
With
the
tension
released,
the
belt
may
be
easily
changed
from
one
step
to
another.
When
the
cone
pulley
guard
is
closed
the
belt
is
automatically
brought
into
tension
again
,
the
amount
of
tension
being
regulated
by
a
slotted
head
screw
located
at
the
rear
of
the
cone
pulley
guard.
Turning
the
screw
to
the
right
increases
the
belt
tension;
to
the
left
decreases
it.
The
Countershaft
The
countershaft
assembly
of
the
Logan
Lathe
is a
patented
development
that
is
a distinct
improvement
over
previous
design.
This
special
unit
assembly
is
carried
by
two
hinged
pins
attached
to a
bracke
t in
the
headstock
and
by
a
pedestal
to
the
floor
or
the
bench
giving
three
point
suspension
. To
prevent
vibration
being
transmitted
to
the
lathe
,
the
entire
assembly
is
insulated
by
rubber
at
all
points
of
contact.
The
two
hinge
pins
are
rubber
cushioned
and
the
cone
pulley
guard
rests
on
rubber
buttons.
Provision
is
made
to
adjust
belt
tension
4
GUARD
FOR
2-S
TE
P
P
ULL
E
YS
AND
V B
ELT
MOTOR CONTROl
SWITCH
RU
B
BE
R INS
ULATED
SU
PP
O
RT
PIN
GUARD
FOR
CO
NE
PULLE
YS
AND F
LAT
B
EL
T
RUBB
ER
TIPS
FIGURE
2-END
VIEW
OF COUNTERSHAFT ASSEMBLY
easily.
An
adjustable
motor
mounting
bracket
is
in-
cluded
in
the
assembly
. All
pulleys
and
belts
are
com
-
pletely
guarded,
yet
easily
accessible
. A
patented
tension
release
operates
automatically
when
the
cover
for
the
cone
pulleys
is
raised
to
permit
quickly
chang
-
ing
the
flat
belt
from
one
step
to
another.
And
finally
,
the
entire
assembly
is
designed
to
appear
as
a
stream-
lined
part
of
the
lathe.
Fig
. 2
above
illustrates
the
floor
model
lathe
and
countershaft
assembly
in
position
.
The
bench
model
uses
the
same
countershaft
design
adapted
for
bench
use
.
The
Headstock
The
headstock
of
the
Logan
Lathe
is
made
of
high
grade
gray
iron
and
is
totally
enclosed.
It
contains
the
headstock
spindle
and
bearings,
the
bull
gear,
the
cone
pulley
and
the
back
gears.
The
cone
pulley
is
turned
by
the
belt
from
the
countershaft,
and
thereby
turns
the
bull
gear,
or
transmits
its
power
through
the
back
gears
to
the
bull
gear
if
lower
speed
or
greater
power
are
desired.
High
carbon
mach
i
nery
steel
has
been
used
in
making
the
sp
i
ndle,
which
has
been
machined
and
ground
to a
fine finish.
The
nose
is
2¥4-in.
diam.
with
8-pitch
National
Form
threads.
~
MOTOR
DRIVE
GUARD
CONE
PINION
GEAR
FIGURE
3-HEADSTOCK
AND
COUNTERSHAFT
GUARD
CONE
COUNTERSHAFT
PUllEY
A
reducing
sleeve
permits
the
use
of a
No.2
Morse
Taper
Center.
The
1%-in.
hole
permits
work
as
large
as
l-in.
to
be
fed
through
the
spindle.
A
draw-in
collet
attach-
ment
taking
collets
up
to
l-inch
capacity
can
be
used
through
the
hollow
spindle.
The
spindle
is
mounted
on
two
New
Departure
precision
ball
bearings
which
are
sealed
in
grease.
The
use
of
ball
bearings
in
the
headstock
to
mount
the
spindle
is
advanced
design
that,
although
more
expensive,
gives
finer
results.
Ball
bearings
are
the
ideal
frictio.1
reducing
bearings-"nothing
rolls like a
ball."
Technical
advances
in
ball
bearing
manufacture
make
it
possible
now
to
obtain
special
pre-loaded
ball
bearings
of
extreme
pre-
cision
that
will
carry
the
loads
for
which
they
are
de-
signed
with
less
wear,
greater
accuracy
and
with
no
adjustment
required.
The
three-step
cone
pulley
and
the
cone
pmwn
gear
are
fastened
together
rigidly
and
revolve
freely
on
the
spindle.
For
direct
drive,
the
pulley
is
locked
to
the
large
bull
gear
which
is
keyed
to
the
spindle.
This
is
accom-
plished
by
means
of a
plunger-type
lock
located
on
the
side
of
the
bull
gear.
When
this
lock
is
"in"
the
pulley
turns
the
bull
gear
with
it;
when
"out"
the
pulley
and
the
cone
pinion
gear
turn
iree
of
the
bull
gear.
Should
it
ever
be
necessary
to
remove
the
headstock
spindle
the
following
procedure
should
be
followed_
First,
remove
the
take-up
nut.
the
spindle
gear,
Wood-
5
ruff
key,
collar,
and
bearing
grease
seal
in
the
order
named
from
the
left
hand
end
of
the
spindle.
Second,
remove
the
four fillister
head
screws
from
the
bearing
cap,
then
the
bearing
cap
and
next
the
grease
seal
from
the
right
hand
end
of
the
spindle.
Third,
loosen
the
set
screws
in
the
bull
gear
and
care-
fully
drive
the
spindle
with
a
wooden
mallet
toward
the
tailstock
end
of
the
lathe,
being
careful
to
hold
the
bull
gear
and
cone
pulley
parts
as
the
spindle
is
re-
moved
so
they
will
not
drop.
Important
Ball
bearings
can
be
ruined
by
improper
handling.
When
pressing
a
bearing
into
or
out
of
the
seat.
pressure
should
be
applied
to
the
outer
race
only,
but
when
pressed
on
to
or
off of
shaft,
pressure
should
be
applied
on
the
inner
race
only.
Bearings
should
be
carefully
kept
free of dirt
and
grit
and
except
in
extreme
cases
should
not
be
tapped
into
place
with
a he-mmer.
The
Back
Gears
FIGURE
4-BACK
GEAR DRIVE
The
back
gear
mechanism
on
the
Logan
Lathe
is
en-
closed
in
the
headstock
instead
of
being
located
in
an
exposed
position
as
in
the
usual
construction.
Also,
instead
of
having
to
reach
over
the
top
of
the
head-
stock
to
throw
a
back
gear
lever,
the
Logan
design
permits
controlling
the
back
gear
by
a
knob
on
the
front of
the
headstock.
The
back
gear
is
mounted
on
a
quill
which
turns
on
self-lubricating
bronze
bearings
on
an
eccentric
shaft.
The
knob
operates
a
rack
engaging
a
pinion
which
rotates
the
eccentric
shaft,
thereby
swing-
ing
the
back
gears
into
mesh.
When
the
knob
is
pulled
out,
the
back
gears
are
engaged
and
are
locked
in
posi-
This manual suits for next models
3
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