What happens if I get the epoxy ratio wrong?

Incorrect ratios result in epoxy that either never fully cures (too much resin), cures too quickly and becomes brittle (too much hardener), or remains tacky indefinitely. Always measure carefully and follow the manufacturer's specified ratio.

Should I mix epoxy by weight or volume?

Check your product instructions. Many epoxies specify mixing by volume, but some are measured by weight. Resin and hardener have different densities, so the ratios differ between volume and weight measurements. When in doubt, use the method specified on the packaging.

How can I extend the pot life of epoxy?

Spread the mixed epoxy into a thin layer on a flat surface rather than leaving it in a cup. The mass of epoxy in a container generates heat that accelerates curing. Working in cooler temperatures also extends pot life. Never add solvent to slow the cure.

Can I use epoxy to fill gaps in woodworking?

Yes, epoxy is excellent for gap filling. Mix in wood dust or commercial thickeners to create a paste-like consistency. For structural gap filling, use a slow-set epoxy (30+ minute pot life) to allow full penetration into the wood fibres.

WoodCalcs

Epoxy Mix Calculator — Resin & Hardener Ratios

Calculate exact resin and hardener quantities for two-part epoxy mixing. Get the ratio right for a proper cure.

Mix RatioCheck your product label

Measurement UnitSelect the measurement unit to use

Total Mixed Volume Needed

The total amount of mixed epoxy you need

Price per Litre/Kg (optional)

Enter your supplier price per litre

How We Calculate This

This calculator divides your total required volume into the correct proportions of resin and hardener based on the mixing ratio.

The formula

Resin = Total volume x (resin parts / total parts)

Hardener = Total volume x (hardener parts / total parts)

For example, with a 2:1 ratio and 300ml total: Resin = 300 x (2/3) = 200ml, Hardener = 300 x (1/3) = 100ml.

Frequently Asked Questions

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Last updated: February 2026

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