1. Lathe Accessories Divided into two categories
Work-holding, -supporting, and –driving devices
Lathe centers, chucks, faceplates
Mandrels, steady and follower rests
Lathe dogs, drive plates
Cutting-tool-holding devices
Straight and offset toolholders
Threading toolholders, boring bars
Turret-type toolposts

2. Lathe Centers
Work to be turned between centers must have center hole drilled in each end
Provides bearing surface
Support during cutting
Most common have solid Morse taper shank 60º centers, steel with carbide tips
Care to adjust and lubricate occasionally
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3. Revolving Tailstock Centers
Replaced solid dead centers for most machining operations
Used to support work held in chuck or when work is being machined between centers
Contains antifriction bearings which allow center to revolve with workpiece
No lubrication required between center and work
Types: revolving dead center, long point center, and changeable point center

4. Chucks Used extensively for holding work for machining operations
Work large or unusual shape
Most commonly used lathe chucks
Three-jaw universal
Four-jaw independent
Collet chuck

5. Three-jaw Universal Chuck
Holds round and hexagonal work
Grasps work quickly and accurate within few thousandths/inch
Three jaws move simultaneously when adjusted by chuck wrench
Caused by scroll plate into which all three jaws fit
Two sets of jaw: outside chucking and inside chucking
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6. Four-Jaw Independent Chuck
Used to hold round, square, hexagonal, and irregularly shaped workpieces
Has four jaws
Each can be adjusted independently by chuck wrench
Jaws can be reversed to hold work by inside diameter

7. Cam-lock mating stud on chuck or faceplate
Headstock Spindles
Cam-lock spindle nose
Held by tightening cam-locks using T-wrench
Chuck aligned by taper on spindle nose
Registration lines on spindle nose
Registration lines on cam-lock
Cam-locks
Cam-lock mating stud on chuck or faceplate
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8. Collet Chuck Most accurate chuck Used for high-precision work
Spring collets available to hold round, square, or hexagon-shaped workpieces
Each collet has range of only few thousandths of an inch over or under size stamped on collet

9. Types of Collet Chucks Spring-collet chuck Jacobs collet chuck
One form: Handwheel draws collet into tapered adapter
Another form: Uses chuck wrench to tighten collet on workpiece
Can hold larger work than draw-in type
Jacobs collet chuck
Utilizes impact-tightening handwheel to close collets
Wider range than spring-collet chuck

10. Collet Chuck |
Special adapter fitted into taper of headstock spindle, and hollow draw bar having internal thread inserted in opposite end of headstock spindle. It draws collet into tapered adapter causing collet to tighten on workpiece.
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11. Steadyrest
Used to support long work held in chuck or between lathe centers
Prevent springing
Located on and aligned by ways of the lathe
Positioned at any point along lathe bed
Three jaws tipped with plastic, bronze or rollers may be adjusted to support any work diameter with steadyrest capacity

12. Follower Rest Mounted on saddle
Travels with carriage to prevent work from springing up and away from cutting tool
Cutting tool generally positioned just ahead of follower rest
Provide smooth bearing surface for two jaws of follower rest

13. Cutting-Tool-Holding Devices
Available in three styles
Left-hand offset
Right-hand offset
Straight
Each has square hole to accommodate square toolbit held in place by setscrew
Angle of approximately 15º to 30º to base of toolholder

14. Left-Hand Offset Toolholder
Offset to the right
Designed for machining work close to chuck or faceplate and cutting right to left
Designated by letter L
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15. Right-Hand Offset Toolholder
Offset to the left
Designed for machining work close to the tailstock and cutting left to right
Also for facing operations
Designated by letter R
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16. Straight Toolholder General-purpose type
Used for taking cuts in either direction and for general machining operations
Designated by letter S
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17. Carbide Toolholder
Has square hole parallel to base of toolholder to accommodate carbide-tipped toolbits
Hold toolbit so there is little or no back rake
Designated by letter C
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18. Cutting-Off (Parting) Tools
Used when work must be grooved or parted off
Long, thin cutting-off blade locked securely in toolholder by either cam lock or locking nut
Three types of parting toolholders
Left-hand
Right-hand
Straight

19. Threading Toolholder
Designed to hold special form-relieved thread-cutting tool
Has accurately ground 60º angle
Maintained throughout life of tool
Only top of cutting surface sharpened when becomes dull

20. Compound Rest Tooling Systems
Standard, or round, toolpost
Generally supplied with conventional engine lathe
Fits into T-slot of compound rest
Provides means of holding and adjusting type of toolholder or cutting tool required
Concave ring and the wedge or rocker provide for adjustment of cutting-tool height

21. Super Quick-Change Toolpost
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