CNC router bits and carbide cutting tools with tutorials and technical guides

3-flute Hardwood, Inlay, Fret and Contour Bits (MM3I8) - (0.125 in. shank)

UltraBIT 3-flute cutters were originally designed for cross-grain cutting in ebony and dry rosewood. Their deflection tolerant design supports high chip-loads and deeper cutting than 2-flute designs. As such, they are often used for cutting the fret slots (kerfs) in fingerboards and high-precision inlay pockets. The enhanced rigidity of the three flute design insures minimum point deflection (wander) under high feed rates.

When cutting rosewood, ebony or african blackwood fingerboards (Janka value greater than 2,700 lbf) or any wood with a high silica content, it is better to use a relieved-neck shell cutter (MS3I8 family) because of their superior stiffness and resistance to breakage.

Manufactured in the USA, every tool is:

  • 100% measured / optically inspected to insure that EVERY tool meets, or exceeds, our published specifications
  • available with depth rings precisely positioned to ±0.004 in. (0.038mm), virtually eliminating the need for resetting Z-axis zero between tool changes (with bits of same overall length)
  • made from premium grade submicrograin tungsten carbide (HRa 92, HRc 80)

This attention to detail and the use of top quality materials result in tools with dependable cutting characteristics and one of the longest tool lives in the market. Combined with comprehensive customer support, our cutters have become the tools of choice for sign makers, model makers, artists and instrument builders around the world.

MADE IN USA

  • Geometry - 3 flute, 1/8 in. shank, fish tail point
  • Length - 1.5 in. ±0.010 in.
  • Diameter - nominal ±0.0005 in.
  • Max runout (TIR) - < 0.0005 in.
  • Max. depth of cut - nominal ±0.005 in.
  • Anticipated Life - 3,000 linear inches (cross-grain ebony, CNC milling)
  • Material - solid submicrograin carbide
  • Ring Set - 0.800 in. ±0.002 in. (optional)
  • Operating RPM - CNC certified operation 20k RPM to 100k RPM
  • Feeds/speeds - to determine the optimum Feed/Speed combinations,
    run our Sweet-spot Test.
  • Fish tail point eliminates backside breakout and splintering
  • High flute volume supports high feed rates / chip loads
  • 3-Flute design eliminates chatter at high feed rates
  • 3-Flute design brings the rigidity and precision of a stub mill to a high-aspect ratio cutter.
  • Cutting edge geometry tuned for cross-grain ebony machining
  • Cutting fret slots in rosewood and ebony finger boards
  • Clean-up cutting of inlay pockets and components
Carbide 3-flute end mills for maching hardwoods, composites and reconstituted minerals

Diameter LOC Reach Flutes Coating Shank OAL Depth Rings Reviews Part Number Price
0.0156" (0.40mm) 0.06" (1.52mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0156-006F

$19.84

0.0200" (0.51mm) 0.09" (2.29mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0200-009F

$19.84

0.0220" (0.56mm) 0.09" (2.29mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0220-009F

$19.84

0.0220" (0.56mm) 0.09" (2.29mm) 3 ZrN 1/8" 1.50" (38.1mm) Available MM3I8-0220-009FC

$23.69

0.0220" (0.56mm) 0.09" (2.29mm) 0.26" (6.6mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0220-026FN

$25.70

0.0230" (0.58mm) 0.09" (2.29mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0230-009F

$19.84

0.0230" (0.58mm) 0.09" (2.29mm) 3 ZrN 1/8" 1.50" (38.1mm) Available MM3I8-0230-009FC

$23.69

0.0230" (0.58mm) 0.09" (2.29mm) 0.26" (6.6mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0230-026FN

$25.70

0.0250" (0.64mm) 0.10" (2.54mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0250-010F

$19.84

0.0250" (0.64mm) 0.13" (3.30mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0250-013F

$19.84

0.0313" (0.79mm) 0.10" (2.54mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0313-010F

$12.23

0.0313" (0.79mm) 0.14" (3.56mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0313-014F

$12.23

0.0313" (0.79mm) 0.16" (3.94mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0313-015FT

$12.75

0.0313" (0.79mm) 0.17" (4.32mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0313-017F

$12.92

0.0320" (0.81mm) 0.16" (3.94mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0320-015FT

$12.75

0.0370" (0.94mm) 0.17" (4.32mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0370-017F

$11.22

0.0380" (0.97mm) 0.17" (4.32mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0380-017F

$11.22

0.0394" (1.00mm) 0.20" (5.08mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0394-020F

$11.22

0.0469" (1.19mm) 0.20" (5.08mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0469-020F

$12.23

0.0500" (1.27mm) 0.25" (6.35mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0500-025F

$12.23

0.0560" (1.42mm) 0.25" (6.35mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0560-025F

$12.23

0.0625" (1.59mm) 0.31" (7.87mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0625-031F

$12.92

0.0625" (1.59mm) 0.31" (7.87mm) 3 ZrN 1/8" 1.50" (38.1mm) Available MM3I8-0625-031FC

$16.22

0.0630" (1.60mm) 0.31" (7.87mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-0630-031F

$12.92

0.1250" (3.18mm) 0.50" (12.70mm) 3 1/8" 1.50" (38.1mm) Available MM3I8-1250-050F

$13.79

0.1250" (3.18mm) 0.50" (12.70mm) 3 ZrN 1/8" 1.50" (38.1mm) Available MM3I8-1250-050FC

$17.09