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End MillRouterMade in USA

C8-203-06

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

0.1875-in Dia 2-Flute End Mill, 0.625-in LOC, 0.25-in Shank, 2.5-in OAL

OrderingC8-203-06·Uncoated·$71.55Change finish

2 Flute Standard Length C-2 Grade Carbide End Mill on 1/4" Dia. Shank — C8-203-06
Series photo — representative of the C8-203 family
OAL 2.5″Flute 0.625″Shank Ø0.25″Cutter Ø0.1875″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
0.1875″
Diameter ToleranceDC tol
0.0000/-0.0020
Max Cutting DiameterDCX
0.1875″
Shank DiameterDMM
0.25″
Length of Cut (LOC)APMX
0.625″
Overall Length (OAL)OAL
2.5″
Number of FlutesNOF
2
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
C8-203 — 2 Flute Standard Length C-2 Grade Carbide End Mill on 1/4" Dia. Shank

Cuts these materials

AluminumCopper & BrassMagnesiumPlasticsCompositesWood

Applications

SlottingSide MillingHelical InterpolationHigh 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

Choose the finish(2 options)

Compare →

Each finish is a different part number and price.

Not sure? Compare tool coatings — or leave it uncoated, the most common choice for aluminum.

Uncoated · your price$71.55

Part C8-203-06

Made & shipped in the USA · lead time confirmed at order. Test this tool in your spindle at retail, or get it through your RobbJack distributor.

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

Adds C8-203-06 · Uncoated · $71.55

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Download ISO 13399 data (.csv)

Proven in the field

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Uncoated

$71.55

C8-203-06

Starting speeds & feeds for the C8-203-06

Dial in for your machine →

RobbJack's tested starting numbers for this exact tool, from the same engine and the same default machine as the calculator: a 12,000 RPM / 400 IPM / 30 HP machining center, rigid setup, full-depth cut. A faster or smaller spindle changes the RPM and feed — enter yours in the calculator and it re-governs every number.

Starting speeds and feeds for RobbJack C8-203-06
MaterialOperationSFMRPMFeed (IPM)Chip load / toothDOC (in)WOC (in)
6061(T4-T6) AluminumRoughing — full slot59012,000115.2.00480.1875.1875
6061(T4-T6) AluminumFinishing59012,00057.6.00240.1875.0094
Free-Cutting BrassRoughing — full slot59012,00057.6.00240.1875.1875
Free-Cutting BrassFinishing59012,00028.8.00120.1875.0094
AcetalRoughing — full slot59012,000115.2.00480.1875.1875
AcetalFinishing59012,00057.6.00240.1875.0094

Read before you run

Recommendations are computed starting points based on typical conditions — not guarantees of performance, tool life, or fitness for your application. Machining involves inherent risk: you are solely responsible for safe operation, for verifying every parameter against your machine, spindle, toolholding, workholding, and guarding limits, and for proving all parameters on a test cut before production. RobbJack Corporation assumes no liability for tool breakage, machine damage, scrapped parts, production loss, or personal injury arising from use of these recommendations. By using this calculator you accept RobbJack's Terms & Conditions.

More in the C8-203 series

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