RC-2251 Insert Carbide Spoilboard Surfacing, Rabbeting, Flycutter, Slab Leveler & Surface Planer 2+2 Flute Design 2-1/2 Dia x 15/32 x 1/2 Shank Router Bit


Diameter (D) 2-1/2
(B) Cutting Height 15/32
Shank (d) 1/2
Overall Length (L) 1-1/2
Max Rpm 19,000


Features unique 2+2 insert knife design that contains two cutting flutes and two up-shear scorers, which provide a smoother finish at the bottom of the cut than traditional two-knife style router bits. A great tool for fast removal of materials over a large surface area. The scorer leaves an improved finish at the bottom of the cut. Great for surface planing.

Also suitable for router sled machines,

Make sure that your router sled is fully stable and squared.

Perfect for:

  • Flattening live edge slabs using router sleds/mills or CNC machines
  • Resurfacing spoilboards using CNC
  • 2+2 spoilboards contain two bottom scorers for better performance, finer surface finish and better clearance for 90º corners.
  • Planing large glued up panels using CNC
  • Surfacing and finishing wood using timber slab machines
  • Rabbeting or slotting

Designed for planing & rabbeting the following materials:

  • MDF
  • Fiberboard
  • Balsa Core*
  • Epoxy (Epoxy Resins)*
  • High Density Urethane (HDU Board)*
  • Plastic/Acrylic**
  • Plywood/Chipboard*
  • Hardwood/Softwood*
  • Ultra-High-Molecular-Weight Polyethylene (UHMWPE)*

*For optimal results and maximum insert life, replace inserts with optional general purpose knives #AMA-12 and #RCK-70 (sold separately).

** Use lower CNC spindle RPM and adjusted feed-rate to prevent Melting and adhesion of the acrylic material to the tool.


  • 2+2 design
  • 4-sided solid carbide insert knives
  • Exclusive carbide grade for highest quality of cut
  • Maximum cutting efficiency
  • Faster material removal process


These industrial router bits feature solid carbide insert knives with four cutting edges that allow users to rotate the knife when one side becomes dull providing the highest-quality finish available on woodworking tools.Recommendations: For surfacing solid woods it is recommended to remove both bottom scorers.

Proper torques rating to tighten down screws is 2-3Nm Torques.


(D) Diameter 2-1/2
(B) Cutting Height 15/32
(d) Shank 1/2
Overall Length (L) 2-1/2
Max RPM 19,000