parts of a lathe

1. Parts of a Lathe
S.Gunabalan
Associate Professor
Mechanical Engineering Department
Bharathiyar College of Engineering & Technology
Karaikal - 609 609.
e-Mail : gunabalans@yahoo.com

2. Parts of a Lathe

3. Headstock
 Holds lathe spindle
and gears
 Chuck is fitted to
spindle
 Spindle is hollow for
long bars

4. Carriage
Moves the cutting tool
along bed between
tailstock and headstock

5. Carriage
4-Way Tool Post.
Mounts up to four cutting tools at
a time and rotates to index each of
them to the workpiece as needed.
Compound Rest Hand wheel.
Moves the tool relative to the
workpiece at the set angle. The
attached indirect graduated dial
has 0.001" (0.02mm) increments,
with one full revolution equaling
0.100" (2.54mm) of travel.
Carriage Handwheel
Moves the carriage longitudinally
along the bedway. The attached
graduated dial has 0.020“ increments
with one full revolution equaling
0.100" of travel.

6. Carriage
Carriage Lock.
Secures the carriage in
place on the bedway
for additional rigidity
when the carriage
should not move
during the operation.
Saddle.
Supports the
cross slide,
compound rest,
and tool post over
the bedway.

7. Carriage
Compound Rest
Angle Scale.
Displays the angle of
the compound rest
left or right from the
spindle center line in
increments of one
degree.
Feed Selection Lever.
Selects either the carriage
or cross slide for power
feed operations. When in
the neutral (middle)
position, power feed is
disabled. This lever works
in conjunction with the
feed knob.

8. Carriage
Thread Chasing
Dial Assembly.
Displays the correct
position to engage
the half nut when
inch threading.
Half Nut Lever.
Engages/disengages
the half nut with
the longitudinal
lead screw for
threading
operations

9. Carriage
Feed Knob.
When tightened, engages either the carriage or
cross slide for power feeding. Conversely, when
loosened, disengages power feed. If the feed
selection lever is in the neutral position or the
half-nut is engaged, the feed knob has no effect.
Half Nut Lever.
Engages/disengages
the half nut with
the longitudinal
lead screw for
threading
operations

10. Carriage
Feed Knob.
When tightened, engages either the carriage or
cross slide for power feeding. Conversely, when
loosened, disengages power feed. If the feed
selection lever is in the neutral position or the
half-nut is engaged, the feed knob has no effect.
Cross Slide
Handwheel.
Moves the cross
slide toward or
away from the
spindle centerline.

11. Cross Slide
Handwheel.
Moves the cross
slide toward or
away from the
spindle centerline.
Compound Rest Angle Scale.
Displays the angle of the
compound rest left or right
from the spindle centerline in
increments of one degree.
Compound Rest Hand
wheel. Moves the tool relative
to the workpiece at the set
angle.

12. LATHE BED
 Made from Gray Cast Iron
 Accurately machined
slideways
 Slideways guide carriage
& tailstock
 Headstock on upper end
of the lathe bed

13. Lathe parts
• Tailstock
 Can be moved along
slideways
 Can be clamped
in any location
 Inside tapered
to hold drill chuck

14. Lathe parts
• Cross Slide
 Fitted on the Saddle
 Moves cutting tool at
right angles to lathe
bed

15. Lathe parts
• Feed shaft
 Used to move the
Carriage
automatically
• Lead screw
 Used when screw
cutting on the lathe

16. Lathe Parts
• Three Jaw Chuck
 Self centring
 Holds round and
hexagonal work
 3 jaws are connected
 Jaws are stamped 1,2 & 3
and fitted in order
 Chuck key used to open

17. Lathe parts
• Toolpost
 Fitted on top slide and
carries the cutting tool
or the cutting tool
holder
 Can adjust the height
on some types
 Can carry 4 different
tool holders

18. Lathe parts
• Tool holders
 Used for holding
cutting tool bits
 Available in Right
hand, left hand and
straight

19. • Cutting Tools
 Can be High Speed
Steel held in tool
holders
 Can be also Ceramic
(Tungsten carbide)
bits held directly in
toolpost