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End MillRouterMade in USA

NR-204-08

2 Flute Standard Length C-2 Grade Carbide End Mill

0.25-in Dia 2-Flute End Mill, 0.75-in LOC, 0.25-in Shank, 2.5-in OAL

OrderingNR-204-08·Uncoated·$72.50Change finish

2 Flute Standard Length C-2 Grade Carbide End Mill — NR-204-08
Series photo — representative of the NR-204 family
OAL 2.5″Flute 0.75″Shank Ø0.25″Cutter Ø0.25″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 NR Series C-2 grade carbide end mill, standard length

2, 3, and 4 flute C-2 grade carbide end mills in standard length -- an economical non-ferrous line in 64th-inch sizes from 1/16" to 1", with explicit flats and no-flats part numbers and DLC coating.

  • C-2 carbide grade, square end, 30-degree helix, standard length in three flute counts: NR-204 (2 flute), NR-303 (3 flute), NR-404 (4 flute)
  • Comes in 64th-inch sizes -- 2 and 4 flute tables run from 1/16" to 1" including half sizes; 3 flute from 1/16" to 3/4"
  • Flats and no-flats versions carry distinct part numbers: sizes on 3/8" and 1/2" shanks (plus 5/8", 3/4", 1") are listed both with flats and as -NF no-flats tools; smaller sizes come without flats
  • Coating options are uncoated or DLC (Diamond-Like Carbon), in both flats and no-flats versions
  • Metric MNR-204 (2 flute) and MNR-303 (3 flute) run 2 mm to 25 mm; metric tools do not have flats
  • Applications: slotting, side milling, and helical interpolation (2 and 3 flute), side milling and high performance work from roughing through finishing; run dry, wet, cold air, or spray mist
  • Materials: aluminum, copper, magnesium, plastics, composites, brass, and wood
  • Tolerances: cutting diameter +.001/-.000, shank diameter -.0001/-.0002, flute length +.030/-.000 (1/16" to 5/16") or +.060/-.000 (21/64" to 1"), OAL +/-.060; MNR cutting diameter +.025/-.000 mm

From the RobbJack Applications Guide.

About this series

NR-204 C-2 Grade Carbide End Mills

C-2 grade end mills available with or without flats

The NR is a square-end C-2 Grade carbide end mill offered in 2-flute (NR-204), 3-flute (NR-303) and 4-flute (NR-404) standard-length configurations. It comes in 64th sizes and is available both with flats and without flats (NF). Cutting diameters range from 1/16" to 1".

  • 2, 3 and 4 flute, square end
  • 30 degree helix
  • Available with flats or no flats (NF)
  • Comes in 64th sizes
  • Cutting Dia. tolerance +.001/-.000

Available uncoated and in Diamond-Like Carbon (DLC) coating

Headline spec

Cutting diameters 1/16"-1"; shanks 1/8"-1"; 1-1/2" to 4" OAL

Best for

  • Side milling
  • Slotting
  • Helical interpolation
  • High-performance roughing
  • Semi-finishing
  • Finishing
  • Aluminum, copper, magnesium, plastics, composites, brass and wood

Specifications

US machining terms with ISO 13399 codes.

Cutting DiameterDC
0.25″
Diameter ToleranceDC tol
0.0010/0.0000
Max Cutting DiameterDCX
0.251″
Shank DiameterDMM
0.25″
Length of Cut (LOC)APMX
0.75″
Overall Length (OAL)OAL
2.5″
Number of FlutesNOF
2
Helix AngleFHA
30°
Helix HandFHH
Right-hand
Cut Direction
Right-hand cut
End Type
Square End
Center Cutting
Yes — plunges
Shank Flats
Standard
Series
NR-204 — 2 Flute Standard Length C-2 Grade Carbide End Mill

Cuts these materials

AluminumCopper & BrassMagnesiumPlasticsComposites

Applications

SlottingSide MillingHelical InterpolationHigh PerformanceRoughingSemi-FinishingFinishingDryWetCold AirSpray Mist

See it run

Tolerances

TypeMinMax
Cutting Diameter+0.0010
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$72.50

Part NR-204-08

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 NR-204-08 · Uncoated · $72.50

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Download ISO 13399 data (.csv)

Proven in the field

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Uncoated

$72.50

NR-204-08

Starting speeds & feeds for the NR-204-08

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 NR-204-08
MaterialOperationSFMRPMFeed (IPM)Chip load / toothDOC (in)WOC (in)
6061(T4-T6) AluminumRoughing — full slot78612,000153.6.00640.2500.2500
6061(T4-T6) AluminumFinishing78612,00076.8.00320.2500.0125
Free-Cutting BrassRoughing — full slot75011,46073.3.00320.2500.2500
Free-Cutting BrassFinishing75011,46036.7.00160.2500.0125
AcetalRoughing — full slot78612,000153.6.00640.2500.2500
AcetalFinishing78612,00076.8.00320.2500.0125

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 NR-204 series

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