AL3-304-24-BN
3 Flute Aluminum Chatter Reduction Hi-Performance Long Len. Carbide End Mill
0.75-in Dia 3-Flute End Mill, 3-in LOC, 0.75-in Shank, 5-in OAL, 0.375 CR, with Chip Breakers
OrderingAL3-304-24-BN·Uncoated·$619.35Change finish
Next-generation 3-flute aluminum end mills with Mirror Edge chatter reduction — standard, long, and extra-long lengths to 5" of flute, with corner radii, ball ends, thru-coolant, and chip breakers on the long tools.
- 3 flute, 35° helix, with Mirror Edge and polished flutes — the guide's 'NEXT GENERATION' chatter-and-vibration eliminator for aluminum
- Three lengths per diameter: AL3-303 standard, AL3-304 long, AL3-305 extra-long — up to 5" flute length on an 8" OAL at 1" diameter
- Inch sizes 1/8"–1"; corner options from sharp corner through radii of .01", .03", .06", .09", .12", .19", and .25" (by diameter) plus ball-end (-BN) versions
- All AL3-304 (long) and AL3-305 (extra-long) tools come standard with chip breakers to control chips
- Four ways to buy every geometry: uncoated, DLC coated, thru-coolant uncoated (-TC), and thru-coolant DLC (-TC-DLC); on 1/8" and 3/16" diameters the thru-coolant version is a non-center-cutting single thru hole
- Guide depth-of-cut guidance by length: AL3-303 at 50% radial width and 2–3 × diameter axial depth; AL3-304 at 30% radial and 4 × diameter at 70% CLPT; AL3-305 at 10% radial and 5 × diameter at 70% CLPT
- Spring passes with long and extra-long tools may be needed to improve finish and deflection — RobbJack tested up to 4 spring passes with AL3-305 using the entire cutting length
- Applications: slotting, side milling, helical interpolation, ramping, high-performance roughing, semi-finishing, and finishing — wet; materials: aluminum, copper, magnesium, brass
- h4 shank tolerance for up to 150% more gripping force; series tolerances: cutting dia −.0007/−.0015, shank −.0001/−.0002, flute length +.060/−.000, OAL ±.060
- Due to the large offering, many AL3 items are made to order and non-returnable (per the guide)
From the RobbJack Applications Guide.
About this series
AL3 3 Flute High Performance Aluminum Carbide End Mill
Aluminum Machining Without Chatter!
The AL3 is RobbJack's 3-flute high-performance aluminum carbide end mill, engineered for chatter reduction with a polished, mirror-edge finish. It is available in Standard, Long, and Extra-Long lengths, square end, corner radius, and ball end, in uncoated, DLC-coated, thru-coolant, and thru-coolant DLC-coated configurations.
- 3 flute
- 35° helix
- Polished mirror edge
- Eliminates chatter and vibration
- Thru coolant holes available
- DLC (Diamond-Like Carbon) coating available
- Long (AL3-304) and Extra-Long (AL3-305) lengths come standard with chip breakers to control chips
- Standard, Long, and Extra-Long lengths with radii
Applications: slotting, side milling, helical interpolation, ramping, high-performance roughing, semi-finishing, finishing, profiling (wet). Tested up to 4 spring passes without problems on AL3-305 using the entire cutting length.
Headline spec
h4 shank tolerance for up to 150% more gripping force — tightest in the industry
Best for
- Aluminum (incl. 6061-T6, 6061-T3, 7075, 2024)
- Copper
- Magnesium
- Brass
Specifications
US machining terms with ISO 13399 codes.
- Cutting DiameterDC
- 0.75″
- Diameter ToleranceDC tol
- -0.0007/-0.0015
- Max Cutting DiameterDCX
- 0.749″
- Shank DiameterDMM
- 0.75″
- Length of Cut (LOC)APMX
- 3″
- Overall Length (OAL)OAL
- 5″
- Corner RadiusRE
- 0.375″
- Number of FlutesNOF
- 3
- Helix AngleFHA
- 35°
- Helix HandFHH
- Right-hand
- Cut Direction
- Right-hand cut
- End Type
- Ball End
- Center Cutting
- Yes — plunges
- Series
- AL3-304 — 3 Flute Aluminum Chatter Reduction Hi-Performance Long Len. Carbide End Mill
Cuts these materials
Applications
Features
See it run
Tolerances
| Type | Min | Max |
|---|---|---|
| Cutting Diameter | -0.001 | -0.0015 |
| Length of Cut | +0.06 | 0 |
| 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.
Part AL3-304-24-BN
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.
Uncoated
$619.35
AL3-304-24-BN
Starting speeds & feeds for the AL3-304-24-BN
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.
| Material | Operation | SFM | RPM | Feed (IPM) | Chip load / tooth | DOC (in) | WOC (in) |
|---|---|---|---|---|---|---|---|
| 6061(T4-T6) Aluminum | Roughing — full slot | 2,358 | 12,000 | 400 | .01111 | .3200 | .7500 |
| 6061(T4-T6) Aluminum | Finishing | 2,358 | 12,000 | 345.6 | .00960 | .7500 | .0375 |
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 AL3-304 series
Same series, different size — what changes from this tool is shown in red.
- AL3-304-04$55.45Ø 0.125″LOC 0.625″OAL 2″3 FL
- AL3-304-04-010$55.45Ø 0.125″LOC 0.625″CR 0.01″OAL 2″
- AL3-304-04-010-TCØ 0.125″LOC 0.625″CR 0.01″OAL 2″
- AL3-304-04-030$55.45Ø 0.125″LOC 0.625″CR 0.03″OAL 2″
- AL3-304-04-030-TCØ 0.125″LOC 0.625″CR 0.03″OAL 2″
- AL3-304-04-BN$55.45Ø 0.125″LOC 0.625″CR 0.0625″OAL 2″
- AL3-304-04-TCØ 0.125″LOC 0.625″OAL 2″3 FL
- AL3-304-06$62.45Ø 0.1875″LOC 0.75″OAL 2″3 FL
- AL3-304-06-010$62.45Ø 0.1875″LOC 0.75″CR 0.01″OAL 2″
- AL3-304-06-010-TCØ 0.1875″LOC 0.75″CR 0.01″OAL 2″
- AL3-304-06-030$62.45Ø 0.1875″LOC 0.75″CR 0.03″OAL 2″
- AL3-304-06-030-TCØ 0.1875″LOC 0.75″CR 0.03″OAL 2″