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End MillRouterMade in USA

C8-303-04

3 Flute Standard Length C-2 Grade Carbide End Mill on 1/4" Dia. Shank

0.125-in Dia 3-Flute End Mill, 0.5-in LOC, 0.25-in Shank, 2.5-in OAL

3 Flute Standard Length C-2 Grade Carbide End Mill on 1/4" Dia. Shank — C8-303-04
Series photo — representative of the C8-303 family
OAL 2.5″Flute 0.5″Shank Ø0.25″Cutter Ø0.125″Square
Scaled drawing — true to this tool's dimensions (inch)
Speeds & FeedsDialed to this exact tool — free
Free CAD & DataSTEP 3DDXF 2DISO CSVCAM library
RobbJack C8-301-04 three flute C-2 grade carbide end mill on 1/4 inch shank

All sizes on 1/4" shanks for strength — spiral routers for signmaking, engraving and CNC production.

  • Every size (1/16"-1/4" cutting dia) built on a 1/4" shank for strength and to fit standard router collets
  • C8 = up-shear spiral (chips lift out of the cut); CD8 = down-shear spiral router (presses the surface down for chip-free top faces on laminates and signs)
  • 2 flute stub (C8-201) and standard (C8-203); 3 flute stub (C8-301) and standard (C8-303); down-shear CD8 in 2 flute stub (CD8-201) and regular (CD8-203)
  • 30° helix, square end with chamfer option, C-2 grade carbide
  • DLC coated versions of every C8 size (-DLC)
  • Materials: wood, aluminum, copper, magnesium, brass, plastics, composites
  • Tolerances: cutting dia +.000/-.002 (1/16"-1/4"), shank dia -.0001/-.0002, OAL +/-.060

From the RobbJack Applications Guide.

About this series

C8 C-2 Grade Carbide End Mills

2 and 3 flute C-2 grade end mills on 1/4" shanks for strength

The C8 series is a square-end, C-2 grade carbide end mill with a 30 degree helix, offered in 2 flute (C8-201/C8-203) and 3 flute (C8-301/C8-303) configurations in stub and standard lengths. All sizes are on 1/4" shanks for strength. Offered uncoated or with DLC coating. The same C8 tools also serve as 2 and 3 flute spiral routers for signmaking, engraving and CNC production in wood and plastics.

  • Square end with 30 degree helix
  • 2 and 3 flute, stub and standard lengths
  • All sizes on 1/4" shanks for strength
  • Uncoated or DLC coated

Aluminum, copper, magnesium, plastics, composites, brass, wood

Headline spec

C-2 grade, 30 degree helix, all sizes on 1/4" shanks

Best for

  • Slotting and side milling
  • Helical interpolation
  • Spiral routing for signmaking, engraving and CNC production

Specifications

US machining terms with ISO 13399 codes.

Cutting DiameterDC
0.125″
Diameter ToleranceDC tol
0.0000/-0.0020
Max Cutting DiameterDCX
0.125″
Shank DiameterDMM
0.25″
Length of Cut (LOC)APMX
0.5″
Overall Length (OAL)OAL
2.5″
Number of FlutesNOF
3
Helix AngleFHA
30°
Helix HandFHH
Right-hand
Cut Direction
Right-hand cut
Shank Blend Angle
15°
End Type
Square End
Center Cutting
Yes — plunges
Shear Direction
Up-shear
Series
C8-303 — 3 Flute Standard Length C-2 Grade Carbide End Mill on 1/4" Dia. Shank

Cuts these materials

AluminumCopper & BrassMagnesiumPlasticsComposites

Applications

Side MillingHigh PerformanceRoughingSemi-FinishingFinishingDryWetCold AirSpray Mist

See it run

Tolerances

TypeMinMax
Cutting Diameter0-0.002
Length of Cut+0.030
Overall Length+0.06-0.06
Shank Diameter-0.0001-0.0002
Starting at$55.70

Made & shipped in the USA · lead time confirmed at order. Buy at retail or through your distributor.

Performance guaranteed. Run it against the tool you use today — if it doesn't beat it, we'll make it right.

Adds Diamond-Like Carbon (DLC) · $59.10 — our pick for your material. Choose another finish below.

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Download ISO 13399 data (.csv)

Proven in the field

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Finishes (2)

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Starting at

$55.70

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More in the C8-303 series

Same series, different size — what changes from this tool is shown in red.