1 / 47

Lathe

Lathe. Parts. 1. Headstock. hollow spindle gear box. 2. Tailstock. handwheel locks. 3. Bed (ways). carriage made up of saddle and apron cross slide compound rest (rotates to any angle) & holds tool post half nut lever - used only for cutting threads thread dial

lacey
Télécharger la présentation

Lathe

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

  2. Parts

  3. 1. Headstock • hollow spindle • gear box

  4. 2. Tailstock • handwheel • locks

  5. 3. Bed (ways) • carriage made up of saddle and apron • cross slide • compound rest (rotates to any angle) & holds tool post • half nut lever - used only for cutting threads • thread dial • feed rod - general turning • lead screw (Acme thread) - for threading only

  6. 4. Base

  7. Lathe spindle - internal Morse taper at nose end • centers • collet assemblies

  8. Outside the spindle nose • threaded nose • long taper with drive key • camlock

  9. Spring cleaner

  10. Spindle Tooling

  11. 1. Independent 4 jaw chuck • most precise • most difficult to set up • holds work more securely • oddly shaped pieces • use dial indicator for centering work piece • can reverse jaws • jaws are removed 3,2,1 and returned in order of 1,2,3

  12. 2. Universal 3 jaw chuck • some 2 or 6 jaws • easier to set up • less precise • jaws will not reverse so a separate set of jaws must be used • chucking • normal • external • internal

  13. 3. Drive plate • used with lathe dog to drive work mounted between centers

  14. 4. Face plate • can mount work directly to face of plate • has T-slots

  15. 5. Collets • for small detailed work • range only few thousandths of inch • work pieces to be gripped must not vary more than +/- .003” • rough or inaccurate work - don’t use with collet • never tighten a collet without a workpiece in its jaws • rubber flex collets - have a wider range (about .125”)

  16. 6. Magnetic chuck

  17. Tailstock • jacobs chuck (drills) • taper shank drills • centers

  18. Operating the machine controls

  19. Hand feeding is not used for long cuts • lack of uniformity • poor surface finish

  20. Using power feed and approaching a shoulder, disengage 1/8” before shoulder

  21. Micrometer collar graduations • single depth - tool moves as much as the collar shows • you are actually removing twice as much from the diameter • turn in .020” , actually moves in .020” removing .040” from dia. • some lathes built to compensate - turn in .020”, actually moves in .010” to remove .020” from dia.

  22. Operations on the lathe

  23. 1.) Facing • to obtain flat surface on end of work piece

  24. Why is facing done? • to establish lengths • before center drilling • on parts clamped on face plate

  25. Tool must be at centerline of work

  26. Lock carriage when facing

  27. Can feed in either direction when facing • 1. feed from center to outside • better surface finish • difficult to cut on a solid face in the center • 2. feed from outside to center (preferred) • can take heavier cuts • easier to cut to scribed lines on the circumference of the work

  28. Feed by hand for small diameters

  29. Methods of facing to length • face to layout line • less precise • turn compound slide parallel to the ways and use micrometer dial • most precise

  30. 2.) Center Drilling • also called combination drill and countersink • performed because the hole must have 60 deg angle to clear point of center • range from 1/8” to 3/4” body diameter • don’t feed drill too fast • don’t feed drill too deep

  31. 3.) Turning between centers (done after facing and center drilling)

  32. Adv: • can turn without eccentricity • can turn more of a shaft

  33. Disadv: • no parting • no boring • no drilling

  34. Accessories needed • tailstock center • headstock center • drive plate • lathe dog • knockout bar

  35. Adjust tailstock so the bent tail of the dog moves freely in its slot

  36. Lathe dog tail should not rub on the bottom of the slot

  37. 4.) Turning between chuck and a center

  38. Adv: • quick setup • positive drive

  39. Disadvantage: • eccentricities on a shaft can be caused by chuck jaw inaccuracies • work piece slips endwise into the chuck - come off tailstock center • solutions to this • 1. make chalk mark at chuck to monitor slipping • 2. machine a shoulder on the shaft to contact face of chuck

  40. Cutting tools and tool holders

  41. General Single Point Turning Tools • HSS • Carbide • greater rigidity • greater material removal rates

  42. Tool geometries (shape of tool) • grooving / parting • threading • knurling • boring - boring bar

  43. Tool holders and Tool posts • mounted on compound rest and held in T-slot

  44. 1. Standard type (obsolete) • straight shank • left hand • right hand

  45. 2. Quick change

  46. Tools should be set on the centerline of the work piece for turning (as well as for facing) • can set this by checking with the center in the tailstock • can set this by using a steel rule

  47. Checking alignment of lathe centers (4 methods) • points of centers brought together • tailstock witness marks • test bar - uses dial indicator mounted on tool post • cutting and measuring (most accurate)

More Related