Custom Drill Bits & Reamers

Specialized Cutting Tools for Aerospace Material Removal

Custom drill bits and reamers address material removal challenges that standard catalogue tooling cannot solve — stacked material combinations, deep hole straightness requirements, interrupted cuts in honeycomb assemblies, and micro-finish reaming for hinge bores on flight control surfaces. Metro Precision Engineering Works develops specialized tooling geometries grounded in metallurgy, coolant delivery strategy, and the specific CNC or manual machine context where tools will run.

We support tooling programs for aluminium alloys, titanium, inconel, CFRP/metal stacks, and hardened steels — each presenting distinct shear, heat, and edge wear characteristics. Custom point angles, web thinning, coolant hole layouts, and proprietary edge preparations extend tool life while holding diameter and surface finish windows.

Design & Prototyping

Tool design begins with application data: material specification, hole depth, tolerance class, machine spindle capability, and production volume. We iterate through cut trials on representative material coupons, measuring hole size drift, exit burr formation, and surface roughness before releasing serial tool drawings.

Reamers for interchangeable bushing fits and pin holes receive particular attention to straightness and size control — often the final operation determining assembly fit on critical tooling. Multi-diameter step drills consolidate operations where stack height tolerances permit.

Manufacturing & Reconditioning

Cutting tools are produced via CNC tool and cutter grinding, with carbide and HSS substrates sourced from reputable suppliers. Coatings — TiN, TiAlN, diamond-like carbon where appropriate — are applied through partner facilities with batch traceability.

Regrinding and recoating programs restore worn custom tools to service, preserving the original geometry profiles stored in our engineering archive linked to client part numbers.

Integration With Tooling Programs

Custom drills and reamers are often delivered alongside the jigs and templates they complement — ensuring bushing diameters, stack heights, and machine feeds/speeds are harmonized in a single Metro Precision package. This integrated approach eliminates finger-pointing between tooling supplier and cutting tool vendor when hole quality issues arise on the floor.

• Custom HSS and carbide drill geometries
• Precision reamers for critical fit holes
• Stacked material and exotic alloy expertise
• Regrind and recoating lifecycle support

Provide material stack details and target cycle time when requesting custom cutter development — our engineers optimize flute geometry and coating for your exact machine power curve rather than delivering generic catalog approximations that underperform in production.