MFM-302-12-BN
3 Flute Aluminum Chatter-Free Medium Reach Metric Carbide End Mill
12mm Dia 3-Flute Metric End Mill 13mm LOC, 12mm Shank, 110mm OAL, 6mm CR, 36mm Reach


2 and 3 flute chatter-reduction end mills with necked reach and radii — the tool that took an automotive aluminum part from 41 hours to 1 hour, in short to extra-long reaches.
- 2 flute (FM-201–205) and 3 flute (FM-301–305), 40° helix, with Feather Blend, necked reach, and Mirror Edge chatter reduction
- Four reach lengths per diameter — short, medium, long, and extra-long (e.g. 1/4" tools reach 5/8" to 1-1/16"+ on a 3" OAL); other reach lengths available upon request
- Inch sizes 1/4"–1"; metric MFM line (2 & 3 flute, 201–205/301–305) runs 6–25 mm
- Corner options: square end, radii of .03", .06", .09" (plus .12" on larger sizes), and ball end (-BN); available uncoated or DLC coated
- Guide case story: an automotive aluminum part went from a 41-hour cycle time to 1 hour with the FM Series — no chatter and superfast feed rates at 450 ipm in an aluminum extrusion
- Guide speeds & feeds run at Max RPM with chip loads from .0040 (1/4") to .0160 (1") per tooth in 6061/7075/2024, at typical Z-depths of .150"–.250"
- Guide rule: Z-depth per pass should be deeper than the corner radius to help reduce chatter
- Applications: slotting, side milling, helical interpolation, ramping, high-performance 3-D (2-flute), roughing, semi-finishing, finishing — wet; materials: aluminum, copper, magnesium, brass
- h4 shank tolerance on all tools — up to 150% more gripping force to eliminate tool pull-out
- Series tolerances: cutting dia −.0007/−.0015 (3-flute pages list −.001/−.0015), shank −.0001/−.0002, flute length +.060/−.000, OAL ±.060
From the RobbJack Applications Guide.


About this series
FM / MFM Aluminum Chatter-Free End Mills
High-performance necked-reach aluminum, chatter-free.
Necked-reach solid carbide end mills tuned for clean, chatter-free aluminum cutting at performance feed rates — the high-performance sibling to the high-velocity FMHV line.
Best for
- Aluminum finishing
- Necked-reach work
- Production volume
Specifications
US machining terms with ISO 13399 codes.
- Cutting DiameterDC
- 12 mm
- Diameter ToleranceDC tol
- -0.001/-0.002
- Shank DiameterDMM
- 12 mm
- Length of Cut (LOC)APMX
- 13 mm
- Reach (LBS)SDL
- 36 mm
- Neck DiameterND
- 11.4 mm
- Overall Length (OAL)OAL
- 110 mm
- Corner RadiusRE
- 6 mm
- Number of FlutesNOF
- 3
- Helix AngleFHA
- 40°
- Helix HandFHH
- Right-hand
- Cut Direction
- Right-hand cut
- Blend Angle (neck→shank)
- 15°
- Feather Blend
- 10°
- End Type
- Ball End
- Center Cutting
- Yes — plunges
- Series
- MFM-302 — 3 Flute Aluminum Chatter-Free Medium Reach Metric 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 |
Made & shipped in the USA · lead time confirmed at order. Buy at retail or through your distributor.
Performance guaranteed. Run it against the tool you use today — if it doesn't beat it, we'll make it right.
Adds Diamond-Like Carbon (DLC) · $321.50 — our pick for your material. Choose another finish below.
Proven in the field
- $548,290saved per year drilling carbon-fiber aircraft
- $216,000saved per year trimming aircraft skins
- 1,000%metal-removal increase in Inconel 718 (SPS)
Finishes (2)
Uncoated
MFM-302-12-BN
$281.85
Available to order
MFM-302-12-BN-DLC
$321.50
Available to order
Starting at
$281.85
Performance guaranteed
More in the MFM-302 series
Same series, different size — what changes from this tool is shown in red.
- MFM-302-06$131.70Ø 6 mmLOC 7 mmreach 18 mmOAL 75 mm
- MFM-302-06-050$140.00Ø 6 mmLOC 7 mmCR 0.5 mmreach 18 mm
- MFM-302-06-100$140.00Ø 6 mmLOC 7 mmCR 1 mmreach 18 mm
- MFM-302-06-BN$147.45Ø 6 mmLOC 7 mmCR 3 mmreach 18 mm
- MFM-302-08$154.15Ø 8 mmLOC 9 mmreach 24 mmOAL 80 mm
- MFM-302-08-100$161.85Ø 8 mmLOC 9 mmCR 1 mmreach 24 mm
- MFM-302-08-200$161.85Ø 8 mmLOC 9 mmCR 2 mmreach 24 mm
- MFM-302-08-250$166.80Ø 8 mmLOC 9 mmCR 2.5 mmreach 24 mm
- MFM-302-08-BN$171.60Ø 8 mmLOC 9 mmCR 4 mmreach 24 mm
- MFM-302-10$164.75Ø 10 mmLOC 11 mmreach 30 mmOAL 100 mm
- MFM-302-10-150$168.85Ø 10 mmLOC 11 mmCR 1.5 mmreach 30 mm
- MFM-302-10-250$173.20Ø 10 mmLOC 11 mmCR 2.5 mmreach 30 mm