Drilling Engineering Knowledge Base
Authoritative guides covering the physics of metal shearing, mathematical derivations, standard drill sizing systems, and CNC programming best practices.
Speeds, Feeds & Machining Physics
4 ArticlesThe Complete Guide to Drill Speeds & Feeds
Master the relationship between cutting speed (SFM), spindle RPM, chip load (IPR), and linear feed rate across steel, aluminum, and stainless.
How to Calculate Drill Spindle RPM
Step-by-step mathematical breakdown of the imperial (SFM) and metric (Vc) rotational speed formulas with machine limit clipping.
Drill Feed Rate: Feed per Rev vs Linear Penetration
The mechanics of chip thickness, axial thrust, and calculating programmed machine feed rates (IPM and mm/min).
Cutting Speed (Vc) & Surface Feet per Minute (SFM)
Why surface speed governs tool life, thermal softening of tool substrates, and surface speed guidelines across 8 common alloys.
Drill Geometry & Sizing Standards
3 ArticlesThe Definitive Drill Bit Sizes Guide
Comprehensive breakdown of Fractional Inch, Numbered Wire Gauge (#1–#80), Letter (A–Z), and Metric drill systems.
Drill Point Geometry: 118° vs 135° Split Point
Anatomy of the chisel edge, lip relief angles, self-centering split points, and choosing the optimal point angle for each metal.
Blind vs Through Hole Depth Calculations
Trigonometric tip allowance, tap chamfer lead-in clearance, breakthrough safety margins, and avoiding bottom collisions.
Threading & CNC Programming
2 ArticlesTapping Drill Calculations & Thread Engagement
Why 65%–75% thread engagement prevents tap breakage while preserving 95%+ of full tensile strength. Cut vs roll form taps.
CNC Drilling Canned Cycles: G81, G82, G83, & G73
Fanuc and Haas canned cycle programming. G98 vs G99 retract planes, Q peck depth rules, dwell mechanics, and modal G80 safety.