Horizontal Milling Machines and Accessories

1. Horizontal Milling Machines and Accessories Session 12

2. Horizontal Milling Machines • Manufacturing-type • Cutter height is controlled by vertical movement of headstock • Special-type • Designed for specific milling operations • Knee-and-column-type • Relationship between cutter height and work controlled by vertical movement of table

3. Manufacturing-Type • Used primarily for quantity production of identical parts • Distinctive features • Automatic cycle of cutter and work approach • Rapid movement during non-cutting cycle • Automatic spindle stop

4. Manufacturing-Type • Two common types • Plain manufacturing type • Small plain automatic knee and column type

5. Plain Manufacturing Type Milling Machine

6. Special-Type Machines • Designed for individual milling operations • Used for only one particular type of job • Completely automatic • Employed when hundreds or thousands of similar pieces are to be machined

7. Machining Centers • Capable of handling wide variety of work all in one setup • Straight and contour milling, drilling, reaming, tapping, and boring • Capable of high production rates while still maintaining high degree of accuracy • Rugged construction, reliable controls • Anti-backlash ball screws

8. Machining Centers

9. Knee-and-Column-TypeMilling Machines • Machines in this class fall into three categories: • Plain horizontal milling machine • Universal horizontal milling machines • Vertical milling machines

10. Universal Horizontal Milling Machines • Difference from plain horizontal machine is addition of table swivel housing • Located between table and saddle • Permits table to be swiveled 45º in either direction in a horizontal plane • Used for milling of helical grooves in twist drills, milling cutters, and gears

11. Universal HorizontalMilling Machine

12. Milling Machine Parts • Base • Gives support and rigidity to machine • Acts as reservoir for cutting fluids • Column face • Precision-machined and scraped section used to support and guide knee when moved vertically • Knee • Houses feed mechanism • Attached to column face and moved vertically

13. Milling Machine Parts • Saddle • On top of knee • Moved in or out by means of crossfeed handwheel (manually or automatically) • Swivel table housing • Fastened to saddle on universal milling machine • Enables table to be swiveled 45º either side of centerline

14. Milling Machine Parts • Table • Rests on guideways in saddle and travels left and right • Supports vise and work • Crossfeed handwheel • Used to move table in and out • Table handwheel • Used to move table left and right

15. Milling Machine Parts • Feed dial • Used to regulate table feeds • Spindle • Provides drive for attachments, arbors, cutters • Overarm • Provides for correct alignment and support of arbor and various attachments • Can be adjusted and locked in various positions

16. Milling Machine Parts • Arbor support • Fitted to overarm and can be clamped • Aligns and supports various attachments • Elevating screw • Gives upward or downward movement to knee and table (manually or automatically) • Spindle speed dial • Set by crank used to regulate spindle speed

17. Backlash Eliminator • Eliminates backlash (play) between nut and table lead screw • Permits operation of climb (down) milling • Two independent nuts mounted on lead screw • Nuts engage common crown gear which meshes with rack • Axial movement of rack controlled by backlash eliminator engaging knob on front of saddle • Turning knob in, nuts forced to move along lead screw in opposite directions

18. Machine Backlash Eliminator

19. Milling Machine Accessories • Wide variety of accessories greatly increase versatility and productivity • Accessories classed as fixtures or attachments • Work-holding device fastened to table • Designed to hold workpieces that cannot be readily held in vise or when large quantities are to be machined

20. Milling Machine Attachments • Designed to hold special attachment that increase versatility of machine • Vertical, high-speed, universal, rack milling, slotting • Designed to hold standard cutters • Arbors, collets, and adapters • Designed to hold workpiece • Vise, rotary table, indexing (dividing) head

21. Vertical Milling Attachment • Enables plain or universal milling machine to be used as a vertical milling machine • Mounted on face of column or overarm • Angular surfaces made by swiveling head, parallel to face of column up to 45º either side of vertical • Used for face milling, end milling, drilling, boring and T-slot milling • Universal milling attachment modification allows swiveling in two planes for cutting compound angles

22. Rack Milling Attachment • Used to mill longer gear racks (flat gears) than could be cut with standard horizontal milling machine • Rack indexing attachment included

23. Slotting Attachment • Converts rotary motion of spindle into reciprocating motion • Cutting keyways, splines, templates, and irregularly shaped surfaces • Length of stroke controlled by adjustable crank • Tool slide may be swiveled to any angle in plane parallel to face of column

24. Arbors • Arbors • Used for mounting milling cutter • Inserted and held in main spindle by draw bolt • Shell-end mill arbors • Permit face milling horizontally or vertically • Fit into main spindle

25. Collets and Adapters • Collet adapters • used for mounting drills or other tapered-shank tools in main spindle of machine or vertical milling attachment • Quick-change adapter • Mounted in spindle • Permits such operations as drilling, boring, and milling without change in setup of workpiece

26. Arbors, Collets, and Adapters

27. Milling Machine Vises • Plain vise • Jaws parallel or 90º to axis of spindle

28. Milling Machine Vises • Swivel base vise • Can swivel through 360º in horizontal plane

29. Milling Machine Vises • Universal vise • Can swivel through 360º in horizontal plane and tilted from 0º to 90 in vertical plane

30. FixturingSystems Easy-to-adjust Stop

31. Indexing or Dividing Head • Permits cutting of bolt heads, gear teeth, ratchets • Revolve work as required to cut helical gears and flutes in drills, reamers, and other tools • When connected to lead screw of milling machine

32. Horizontal Boring Mill

33. Horizontal Boring Mill