Vertical and Horizontal Mills
Vertical Mill
Parts
Base and Column Knee Saddle Table Ram Tool Head Quill Feed
Cutter Holding
– No more overhang than is necessary R8 Taper Solid Collet (most rigid) Split Collet
Vertical Milling Cutters
End mills
2 or more flutes single or double end straight or helix flute roughing end mills
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
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
Horizontal Mill
Parts
Base and Column Knee Saddle Table Spindle Overarm
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
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
Milling machine spindle nose tapers
#30, #40, #50 (most common), #60
Cutters may be attached
a. directly to the spindle nose b. on a taper shank arbor (our
application)
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
Horizontal Milling Cutters
Arbor driven cutters (most common)
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
Side milling cutters - for machining steps or grooves
stagger tooth inserted tooth (indexable) 1/2 side
Slitting saws - for slotting and cut-off
stagger tooth inserted tooth (indexable) side
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
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
Day 2
Work holding methods
1.) Vise (most common)
plain vise swivel vise universal vise -swivels 90 deg in vert and
360 in horiz plain
Vise operation
manual air hydraulic
Use a lead or rubber hammer to strike handle to tighten
Keep work piece as far into vise as possible without danger of hitting vise
Proper part orientation in vise for cutting pressures
pressure against solid jaw (best) pressure against movable jaw pressure parallel to jaws (worst)
Soft jaws
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
3.) Pallets
Work edge locating
offset edge finder (accurate) dial indicator (accurate) touch off method (less accurate) paper shim (less accurate)
Hole center locating
Climb (down) vs. Conventional Milling (up)
Selection depends on:
is there backlash compensation required surface finish type of material being cut
Climb milling
results in good surface finish - chips not swept back through cut
avoid unless backlash is compensated for
Conventional milling (normally used)
surface finish not as good
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”
Horizontal Milling Depth of cut - Arbor driven cutters
roughing cuts = .100 to 200” finish cuts = .015 to .030” no less than .015”
Squaring vise and machine head
Vertical Mill
Head squared to table Vise squared to table
Horizontal Mill
Table squared by mounting indicator on table (Never the column)
Vise squared to table with indicator mounted on overarm
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