CMT Top-Bearing Mortising Router Bit 1/2" Dia x 3/4" Cut, 1/4" Shank
HW Z2
Top-Bearing Mortising Bit
CMT 801.127.11B is the exact 1/2-inch cutting-diameter variant in the 7/8/901B top-bearing mortising family. It combines a 3/4-inch cutting length, 2-9/64-inch overall length, 1/4-inch shank, two HW carbide cutting edges, negative shear geometry, right-hand rotation, and a top bearing guide for mortising, sign making, and template-guided routing in natural wood and wood composites.
Main Product Description
CMT 801.127.11B is the exact top-bearing variant in the official 7/8/901B Mortising Router Bits family. The North American row specifies D = 1/2 inch, I = 3/4 inch, L = 2-9/64 inches, S = 1/4 inch, Z = 2, MAT = HW, and RH rotation.
The worldwide metric table confirms the same geometry as a 12.7 mm cutting diameter, 20 mm cutting length, 54 mm overall length, and 6.35 mm shank. CMT equips the family with thick carbide tips and negative shear-angle design to support clean hinge mortises with reduced splintering and smooth bottoms.
The top bearing guide makes this variant suitable for sign making and template work in addition to mortising natural wood and wood composites. The exact row identifies bearing 791.010.00, stop collar 541.001.00, and hex key 991.056.00 as the published assembly/service components for this item.
Best Fit Applications
Product Highlights
Top-Bearing Template Control
The published bearing guide supports mortising, sign making, and accurate template-following work with the cutter positioned below the guide.
Negative Shear Geometry
Thick HW carbide tips and negative shear-angle design help control surface fibres for cleaner mortise edges and smoother recess bottoms.
Verified Service Components
CMT identifies bearing 791.010.00, stop collar 541.001.00, and hex key 991.056.00 for the exact 801.127.11B assembly.
Compatibility & Installation Notes
Use CMT 801.127.11B only in a compatible router with a sound 1/4-inch collet. Inspect bearing 791.010.00 for free rotation and damage, confirm stop collar 541.001.00 is securely positioned, and use the specified hex key 991.056.00 for the related collar hardware. Keep the template, workpiece, and jig firmly secured; verify cutter and bearing clearance before starting; feed against cutter rotation; and follow the router and tool manufacturers' projection and speed limits.
Clean Top-Bearing Mortising and Template-Guided Control
CMT 801.127.11B combines a 1/2-inch cutting diameter, 3/4-inch cutting length, 1/4-inch shank, Z2 HW carbide geometry, and right-hand rotation.
Negative shear design, the top bearing guide, and verified bearing, collar, and hex-key references complete the mortising and template-routing system.