Use this workshop calculation to turn measured dimensions and the selected construction convention into a cut, spacing, fit, or material-planning value.

Shank diameter (mm)

Nail shank diameter in millimetres.

Penetration depth (mm)

Penetration depth in the wood in millimetres.

Wood group

Wood group: softwood (factor 1.0) or hardwood (factor 1.4).

Estimate nail withdrawal resistance in kilograms from shank diameter, penetration depth, and wood group. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Withdrawal resistance (kg)

Estimated withdrawal resistance in kilograms.

• Nominal dimensions, kerf, moisture movement, hardware clearances, wall squareness, and manufacturer instructions can change the required shop dimension. Measure the actual assembly and test critical joints on scrap before cutting finished material.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Complement the calculated dimension with a physical story stick, dry fit, or full-size layout. Follow the hardware, coating, adhesive, or machine manufacturer's limits where they differ from a rule of thumb.

• Screw Pull-Out Estimate

  Estimate screw pull-out resistance in kilograms from core diameter, penetration depth, and wood group.

• Nail Length Rule

  Minimum nail length from the thickness of the attached board and a separately chosen penetration depth into the receiving member; not a withdrawal-capacity check.

• Biscuit Slot Depth Lookup

  Look up the standard joiner plunge depth for size 0, 10, and 20 compressed-wood biscuits.