Vertical and Horizontal Mills

1. Vertical and Horizontal Mills

2. Vertical Mill

3. Parts • Base and Column • Knee • Saddle • Table • Ram • Tool Head • Quill Feed

4. Cutter Holding • No more overhang than is necessary • R8 Taper • Solid Collet (most rigid) • Split Collet

5. Vertical Milling Cutters

6. End mills • 2 or more flutes • single or double end • straight or helix flute • roughing end mills

7. Geometry Forming cutters • dovetail - 45 or 60 degree • t-slot • woodruff key • shell end mills • three flute tapered - used for mold making, die work, patterns

8. Misc cutters • Fly cutters - single point tool often consisting of high speed or carbide tool • take light face cuts from large surface areas • Indexible tooling - many cutter types and shapes • eliminate resharpening • Face mills - flat surfaces

9. Horizontal Mill

10. Parts • Base and Column • Knee • Saddle • Table • Spindle • Overarm

11. Universal Horizontal Mill • similar to plain except it has has an additional housing that supports the table and allows table to swivel 45 deg in either direction in horiz plane • used to machine helical slots or grooves in mill cutters and twist drills, otherwise they are the same as the plain machines

12. Types of spindles, arbors, and adapters • front end of spindle nose has a tapered socket in a standard milling machine taper. This taper aligns the milling machine adapter or cutter arbor • driving force is provided by two keys located on the spindle nose • these engage slots on the adaptor or arbor

13. Milling machine spindle nose tapers • #30, #40, #50 (most common), #60

14. Cutters may be attached • a. directly to the spindle nose • b. on a taper shank arbor (our application)

15. Taper shank arbor assembly • arbor itself • spacing collars - take up space between cutter and end of arbor • bearing collar - rides in arbor support bearing • arbor support bearing - supports outer end of the arbor

16. Horizontal Milling Cutters

17. Arbor driven cutters (most common)

18. Plain arbor driven cutters - for removing material across entire surface (most common operation) - 3 types • 1. light duty - more teeth • 2. heavy duty - less / heavier teeth • Note: any width 3/4” and less will have straight teeth = more chatter

19. Side milling cutters - for machining steps or grooves • stagger tooth • inserted tooth (indexable) • 1/2 side

20. Slitting saws - for slotting and cut-off • stagger tooth • inserted tooth (indexable) • side

21. Geometry forming • single angle - 45 and 60 most common • double angle - 45, 60 and 90 most common • concave - go by the cutter shape not by the geometry created • convex • corner rounding • gear cutters

22. Misc. Horizontal Milling setups • 1. straddle milling • 2. gang milling - to machine special shapes and contours on workpiece • cutter rpm calculated for largest dia cutter in gang

23. Day 2

24. Work holding methods

25. 1.) Vise (most common) • plain vise • swivel vise • universal vise -swivels 90 deg in vert and 360 in horiz plain

26. Vise operation • manual • air • hydraulic

27. Use a lead or rubber hammer to strike handle to tighten

28. Keep work piece as far into vise as possible without danger of hitting vise

29. Proper part orientation in vise for cutting pressures • pressure against solid jaw (best) • pressure against movable jaw • pressure parallel to jaws (worst)

30. Soft jaws

31. 2.) Mounting directly to the table • strap clamps, T-bolts, and step blocks • protect work piece surface with shims when necessary • use parallels or shims under work piece as needed • work piece distorted or damaged with excessive pressures

32. 3.) Pallets

33. Work edge locating • offset edge finder (accurate) • dial indicator (accurate) • touch off method (less accurate) • paper shim (less accurate)

34. Hole center locating

35. Climb (down) vs. Conventional Milling (up)

36. Selection depends on: • is there backlash compensation • required surface finish • type of material being cut

37. Climb milling • results in good surface finish - chips not swept back through cut • avoid unless backlash is compensated for

38. Conventional milling (normally used) • surface finish not as good

39. Vertical Milling Depth of cut - End mills • Roughing cuts with standard end mills in steel - don’t exceed 1/2 dia. cutter dia. • Finish cuts - .005 - .010”

40. Horizontal Milling Depth of cut - Arbor driven cutters • roughing cuts = .100 to 200” • finish cuts = .015 to .030” • no less than .015”

41. Squaring vise and machine head

42. Vertical Mill • Head squared to table • Vise squared to table

43. Horizontal Mill • Table squared by mounting indicator on table (Never the column) • Vise squared to table with indicator mounted on overarm