Conical point geometry

Drill-point depth

Inputs

Drill diameterDDeclared drill diameter used for exact conical point geometry.

Included point angleθDeclared full included conical point angle; it must be between 0 and 180 degrees.

Required full-diameter depthhDepth of the requested full-diameter cylindrical portion, excluding the drill point.

Geometric drill-point depth

2.4853

Programmed depth for declared full diameter

27.485

hpoint = (D/2)/tan(θ/2); hprogram = hfull + hpoint

A first-pass number, not a code check, certification, or approval. Read the method and its limits below. What this is and is not.

Calculation snapshot

Formula version 2.0.0

Drill diameter	12
Included point angle	135
Required full-diameter depth	25

Geometric drill-point depth	2.4853 mm
Programmed depth for declared full diameter	27.485 mm

hpoint = (D/2)/tan(θ/2) · hprogram = hfull + hpoint

Haas drill-point depth guidance: https://www.haas.co.uk/resources/better-techniques/control-tips/working-out-drill-depth/

This printout is a record of displayed inputs and deterministic formula output. It is not an approval, certification, or engineering conclusion.

Method

Calculate geometric drill-point depth and programmed depth for a full-diameter hole depth from drill diameter and included point angle.

hpoint = (D/2)/tan(θ/2); hprogram = hfull + hpoint

When

Don’t

Ideal conical-point geometry only; drilling variation, wear, runout, breakthrough allowance, workholding, machine motion, cutting parameters, safety, and manufacturing approval are excluded.