1 / 63

Lathe Accessories

Lathe Accessories. Session 7. 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

Ava
Download Presentation

Lathe Accessories

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Lathe Accessories Session 7

  2. 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

  3. 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 shank60º centers, steel with carbide tips • Care to adjust and lubricate occasionally

  4. Lathe Centers

  5. 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

  6. Revolving Tailstock Centers

  7. Microset Adjustable Center • Fits into tailstock spindle • Provides means of aligning lathe centers or producing slight tapers on work machined between centers • Eccentric slide (dovetail) allows center to be adjusted limited amount to each side of center

  8. Microset Adjustable Center

  9. Self-Driving Live Center • Mounted in headstock spindle • Used when entire length of workpiece is being machined in one operation • Chuck or lathe dog could not be used to drive work • Grooves ground around circumference of lathe center point provide drive • Work usually soft material such as aluminum

  10. Self-Driving Live Center

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

  12. Three-jaw Universal Chuck • Holds round and hexagonal work • Grasps work quickly and accurate within few thousandths/inch • Three jaws move simultaneously whenadjusted by chuck wrench • Caused by scroll plate into which all three jaws fit • Two sets of jaw: outside chucking and inside chucking

  13. Three-jaw Universal Chuck

  14. 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

  15. Four-Jaw Independent Chucks

  16. Headstock Spindle Types • Threaded spindle nose • Screws on in a clockwise direction • Tapered spindle nose • Held by lock nut that tightens on chuck • Cam-lock spindle nose • Held by tightening cam-locks using T-wrench • Chuck aligned by taper on spindle nose

  17. Threaded Spindle Nose

  18. Tapered Spindle Nose

  19. Cam Lock Spindle Nose

  20. Collet Chucks • 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

  21. Spring Collet Chucks • Spring-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

  22. | Spring Collet Chucks

  23. Spring Collet Chucks

  24. Jacobs Collet Chuck • Jacobs collet chuck • Utilizes impact-tightening handwheel to close collets • Wider range than spring-collet chuck

  25. Jacobs Collet Chuck

  26. Magnetic Chucks • Used to hold iron or steel parts that are too thin or may be damaged if held in conventional chuck • Fitted to an adapter mounted on headstock spindle • Used only for light cuts and for special grinding applications

  27. Magnetic Chucks

  28. Faceplates • Used to hold work too large or shaped so it cannot be held in chuck or between centers • Usually equipped with several slots to permit use of bolts to secure work • Angle plate used so axis of workpiece may be aligned with lathe centers • Counterbalance fastened to faceplate when work mounted off center • Prevent imbalance and resultant vibrations

  29. Faceplates

  30. Faceplates

  31. 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

  32. Steadyrest

  33. 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

  34. Follower Rest

  35. Mandrel • Holds internally machined workpiece between centers so further machining operations are concentric with bore • Several types, but most common • Plain mandrel • Expanding mandrel • Gang mandrel • Stub mandrel

  36. Plain Mandrel

  37. Expanding Mandrel

  38. Gang Mandrel

  39. Stub Mandrel

  40. Lathe Dogs • Drives work machined between centers • Has opening to receive work and setscrew to fasten the dog to work • Tail of dog fits into slot on driveplate and provides drive to workpiece • Made in variety of sizes and types to suit various workpieces

  41. Standard bent-tail lathe dog • Most commonly used for round workpieces • Available with square-head setscrews of headless setscrews

  42. Standard bent-tail lathe dog • Bent tail engages in slot on drive plate

  43. Straight-tail lathe dog • Driven by stud in driveplate • Used in precision turning

  44. Safety clamp lathe dog • Used to hold variety of work • Wide range of adjustment

  45. Heavy Duty Lathe Dog • Wider range than others • Used on all shapes

  46. 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

  47. 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

  48. 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

  49. Straight Toolholder • General-purpose type • Used for taking cuts in either direction and for general machining operations • Designated by letter S

  50. Carbide Toolholder • Has square hole parallel to base of toolholder to accommodate carbide-tipped toolbits • Holds toolbit with little or no back rake • Designated by letter C

More Related