How much clamping pressure do I need?

PVA/Type-I aliphatic glue (Franklin/Titebond) needs about 100-150 psi (690-1034 kPa) for softwoods and 175-250 psi (1207-1724 kPa) for hardwoods, rising towards 300 psi for very dense species such as oak or maple. Over-clamping squeezes out too much glue and starves the joint; under-clamping leaves gaps.

How many clamps do I need for a panel glue-up?

Space clamps 200-300mm apart for edge-glued panels. Alternate clamps above and below to prevent bowing. A 600mm wide panel typically needs 3 clamps per glue line.

What type of clamp is best for woodworking?

F-clamps (bar clamps) are the most versatile. Sash clamps for long panels. Pipe clamps are economical for wide panels. Spring clamps for light-duty work. A light-duty F-clamp delivers around 270 kgf (~600 lbf); medium and heavy-duty F-clamps reach 500-600 kgf (~1100-1320 lbf). The 250kgf default is a conservative light-duty assumption.

WoodCalcs

Clamp Pressure Calculator — Glue-Up Force

Determine clamp force and number of clamps needed for glue-ups.

Glue Area

Length × width of the glued face (e.g. 600mm × 100mm edge joint = 60000 mm²)

Wood TypeSets the target glue-line pressure: softwood ~100-150 psi, hardwood ~175-250 psi (Franklin/Titebond)

How We Calculate This

Total force (kgf) = Pressure (kPa) × 1000 × Area (m²) ÷ 9.81

Clamps = Total force ÷ Force per clamp (~250kgf for a light-duty F-clamp)

Softwood needs ~690-1034 kPa (100-150 psi). Hardwood needs ~1207-1724 kPa (175-250 psi).

Frequently Asked Questions

Related Calculators

Drill Bit Size Calculator

Find the correct drill bit size for screws, dowels, and pilot holes.

Router Bit Speed Calculator

Calculate safe router speeds based on bit diameter and material.

Sandpaper Grit Calculator

Plan grit sequences and calculate sandpaper sheet quantities.

Blade Height Calculator

Calculate optimal table saw blade height for through and partial cuts.

Table Saw Fence Calculator

Work out fence positions for ripping stock to width including kerf.

Last updated: February 2026

All calculations are estimates. Always verify measurements and material quantities before cutting or purchasing.