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End MillRouterMade in USA

C1-401-10

4 Flute Standard Length C-2 Grade Carbide End Mill

0.3125-in Dia 4-Flute End Mill, 0.8125-in LOC, 0.3125-in Shank, 2.5-in OAL

OrderingC1-401-10·Uncoated·$71.90Change finish

4 Flute Standard Length C-2 Grade Carbide End Mill — C1-401-10
Series photo — representative of the C1-401 family
OAL 2.5″Flute 0.8125″Shank Ø0.3125″Cutter Ø0.3125″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 C1-201-16 two flute C-2 grade carbide end mill, 1/2 inch diameter standard length

C-2 grade carbide end mills — the economical 30° helix workhorse for aluminum, plastics and composites.

  • 2 flute (C1-201), 3 flute (C1-301) and 4 flute (C1-401) standard-length square end, all 30° helix
  • C-2 grade carbide substrate
  • 15 inch sizes per flute count from 1/16" to 3/4" diameter, shank matches cutting diameter from 5/32" up
  • DLC (Diamond-Like Carbon) coated versions of every size (-DLC)
  • Metric MC1-201/MC1-301 from 2mm to 25mm diameter
  • Materials: aluminum, copper, magnesium, plastics, composites, brass
  • Tolerances: cutting dia +.000/-.002, shank dia -.0001/-.0002, OAL +/-.060
  • 2 flute rated for slotting, side milling and helical interpolation; 3 and 4 flute for side milling

From the RobbJack Applications Guide.

About this series

C1 C-2 Grade Carbide Standard Length End Mills

Standard-length C-2 carbide end mills in 2, 3, and 4 flute.

The C1 series is an inch-sized line of standard length C-2 grade solid carbide end mills offered in 2-flute (C1-201), 3-flute (C1-301), and 4-flute (C1-401) styles with a 30-degree helix and square end. Cutting diameters range from 1/16 inch up to 3/4 inch.

  • C-2 grade carbide
  • Standard length
  • 30-degree helix
  • Square end
  • 2, 3, and 4 flute versions

Aluminum, Copper, Magnesium, Plastics, Composites, Brass. Diamond-Like Carbon (DLC) coating available; dry, wet, cold air, or spray mist.

Headline spec

Cutting diameters 1/16 inch to 3/4 inch; C-2 grade carbide, standard length.

Best for

  • Slotting
  • Side Milling
  • Helical Interpolation
  • Conventional machining
  • High Performance machining
  • Roughing
  • Semi-Finishing
  • Finishing

Specifications

US machining terms with ISO 13399 codes.

Cutting DiameterDC
0.3125″
Diameter ToleranceDC tol
0.0000/-0.0020
Max Cutting DiameterDCX
0.3125″
Shank DiameterDMM
0.3125″
Length of Cut (LOC)APMX
0.8125″
Overall Length (OAL)OAL
2.5″
Number of FlutesNOF
4
Helix AngleFHA
30°
Helix HandFHH
Right-hand
Cut Direction
Right-hand cut
End Type
Square End
Center Cutting
Yes — plunges
Series
C1-401 — 4 Flute Standard Length C-2 Grade Carbide End Mill

Cuts these materials

AluminumCopper & BrassMagnesiumPlasticsComposites

Applications

Side MillingConventionalHigh PerformanceRoughingSemi-FinishingFinishingDryWetCold AirSpray Mist

See it run

Tolerances

TypeMinMax
Cutting Diameter0-0.003
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$71.90

Part C1-401-10

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 C1-401-10 · Uncoated · $71.90

Calculate Speeds & Feeds
CADDXF·STEP
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Download ISO 13399 data (.csv)

Proven in the field

See the case studies →

Uncoated

$71.90

C1-401-10

Starting speeds & feeds for the C1-401-10

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 C1-401-10
MaterialOperationSFMRPMFeed (IPM)Chip load / toothDOC (in)WOC (in)
6061(T4-T6) AluminumRoughing — full slot98312,000384.00800.3125.3125
6061(T4-T6) AluminumFinishing98312,000192.00400.3125.0156
Free-Cutting BrassRoughing — full slot7509,168146.7.00400.3125.3125
Free-Cutting BrassFinishing7509,16873.3.00200.3125.0156
AcetalRoughing — full slot98312,000384.00800.3125.3125
AcetalFinishing98312,000192.00400.3125.0156

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 C1-401 series

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