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End MillMade in USA

TL-303-08

3 Flute Extra Length Tuffy Grade Carbide End Mill

0.25-in Dia 3-Flute End Mill, 1.25-in LOC, 0.25-in Shank, 3-in OAL

OrderingTL-303-08·$126.10

3 Flute Extra Length Tuffy Grade Carbide End Mill — TL-303-08
Series photo — representative of the TL-303 family
OAL 3″Flute 1.25″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 TL-303 3-flute extra length Tuffy grade carbide end mill

3-flute extra-length Tuffy grade square end mills — long flutes for deep side milling, with shank flats on the larger inch sizes.

  • 3 flute square end extra-length Tuffy grade carbide with 30° helix
  • Long flute lengths for deep walls — up to 3" of flute on the 3/4" tool (5" OAL); metric MTL runs up to 75 mm flute on the 20 mm tool (130 mm OAL)
  • Inch sizes 1/8"–3/4" (TL-303); metric sizes 3–20 mm (MTL-303)
  • Shank flats on the 3/8", 1/2", 5/8", and 3/4" inch sizes for secure holding; 1/8"–5/16" and 7/16" sizes and all metric tools do not have flats
  • Rated for side milling, semi-finishing, and finishing — wet, cold air, or spray mist
  • Broad material range: aluminum, copper, magnesium, cast iron, steel, stainless steel, plastics, brass, and wood
  • Tolerances: cutting dia −.001/−.002 at 1/8" and +.001/−.000 from 3/16"–3/4"; shank −.0001/−.0002; flute length +.060/−.000 (MTL cutting dia +.025/−.000 mm from 4–20 mm)
  • Guide cross-reference for chatter on long reaches: consider the FM Series or add Mirror Edge treatment

From the RobbJack Applications Guide.

Lengthened TL-303 3-flute extra length end mill showing the long flute section

About this series

TL / MTL Extra Length Tuffy Grade Carbide End Mills

3 flute extra-length square-end mills for deep-reach work

The TL-303 is a 3 flute, extra-length, square-end Tuffy Grade carbide end mill with a 30 degree helix. MTL-303 is the metric extra-length version (metric tools do not have flats). Available in inch sizes 1/8" to 3/4" and metric sizes 3 mm to 20 mm.

  • Extra length, 3 flute square end, 30 degree helix
  • Inch (TL) and metric (MTL) versions
  • Metric tools do not have flats

Aluminum, copper, magnesium, cast iron, steel, stainless steel, plastics, brass, wood

Headline spec

Extra length, 3 flute, 30 degree helix

Best for

  • Side milling
  • Semi-finishing and finishing

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
1.25″
Overall Length (OAL)OAL
3″
Number of FlutesNOF
3
Helix AngleFHA
30°
Helix HandFHH
Right-hand
Cut Direction
Right-hand cut
End Type
Square End
Center Cutting
Yes — plunges
Series
TL-303 — 3 Flute Extra Length Tuffy Grade Carbide End Mill

Cuts these materials

AluminumCopper & BrassMagnesiumCast IronSteelStainless SteelPlastics

Applications

Side MillingSemi-FinishingFinishingWetCold AirSpray Mist

See it run

Tolerances

TypeMinMax
Cutting Diameter+0.0010
Length of Cut+0.060
Overall Length+0.06-0.06
Shank Diameter-0.0001-0.0002
TL-303-08In stock$126.10
Uncoated · your price$126.10

Part TL-303-08

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 TL-303-08 · · $126.10

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Download ISO 13399 data (.csv)

Proven in the field

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Starting at

$126.10

TL-303-08

Starting speeds & feeds for the TL-303-08

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 TL-303-08
MaterialOperationSFMRPMFeed (IPM)Chip load / toothDOC (in)WOC (in)
6061(T4-T6) AluminumRoughing — full slot78612,000230.4.00640.2500.2500
6061(T4-T6) AluminumFinishing78612,000115.2.00320.2500.0125
Free-Cutting BrassRoughing — full slot75011,460110.00320.2500.2500
Free-Cutting BrassFinishing75011,46055.00160.2500.0125
AcetalRoughing — full slot78612,000230.4.00640.2500.2500
AcetalFinishing78612,000115.2.00320.2500.0125

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 TL-303 series

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