Drill Calculator logoDrill Calculator
Tool Geometry & Depth Control

Calculadora de Punta de Broca y Longitud de Vértice

Calcule la longitud de punta, tolerancia de profundidad y distancia de traspaso para ángulos de 118°, 135° y personalizados.

Point & Depth Parameters

Calculate drill point offset, tip length, and full machine depth

mm
degrees
Calculated Drill Point Length (l)~0.300 × D
3.60mm
Full Machine Z Travel
33.60 mm
Depth + Point Length
Full Diameter Depth
30.00 mm
Flat cylinder depth
Live Point Geometry Cross-Section118° Point
l = 3.60mmD = 12mm
Formula: l = (D / 2) / tan(θ / 2)

For a standard 118° drill, point length is approximately 0.300 × Diameter. For 135° split points, it is approximately 0.207 × Diameter.

The Mathematics of Drill Point Tip Length

When programming CNC hole drilling or setting manual depth stops, understanding the difference between the cylindrical hole depth (the usable flat diameter) and the total drill tip travel is critical. If a print calls for a 1.000" blind hole, drilling only to 1.000" Z-depth results in an undersized cylindrical depth because the conical point has not completed its diameter!

Fundamental Point Length Equation:
l = (D / 2) / tan(θ / 2)
Where D is the drill diameter, θ is the included point angle (e.g. 118° or 135°), and l is the conical tip length.

118° Standard Point Angle

The traditional general-purpose drill point. Well-suited for mild steels, aluminum, brass, and plastics.

Tip Length ≈ 0.300 × Diameter
Example: 1/2" (12.7mm) drill has a 0.150" (3.81mm) tip length.

135° Split Point Angle

Flatter cone with web thinning. Eliminates chisel edge wandering, penetrates tough stainless steels, and reduces breakthrough burrs.

Tip Length ≈ 0.207 × Diameter
Example: 1/2" (12.7mm) drill has a 0.103" (2.63mm) tip length.