How to Mix Epoxy Resin Correctly (Step-by-Step)

Why Mixing Matters

Most resin problems — sticky patches, soft spots, cloudy cure — trace back to mixing. The resin-to-hardener reaction only completes when the ratio is right and the two parts are blended fully.

What You Need

• Measuring cups with clear markings (or a digital scale if your product specifies weight)
• A flat-bottomed mixing stick or paddle
• Nitrile gloves and a ventilated workspace
• Your resin, hardener and planned pigments

Step-by-Step

1. Measure accurately. Follow the ratio for your exact product — commonly 2:1 or 3:1 by volume. Do not eyeball it. Do not add extra hardener 'to make it harder' — that actually weakens the cure.

2. Combine and mix slowly. Scrape the full contents into a clean cup. Mix steadily for the time your product specifies (often 3–5 minutes), scraping the sides and bottom continuously.

3. Scrape the walls and stick. Unmixed resin hiding on the walls or stirrer is a classic source of sticky streaks.

4. Transfer and mix again (double-cup method). Pour the mix into a second cup and stir briefly. This catches residue from the first cup.

5. Add pigments last. Mix colours in after the base is fully blended, and keep additive amounts within the product's guidance.

6. Pour within the working time. Once mixed, the clock is running. Pour before the resin thickens.

Signs of a Bad Mix

• Sticky or wet spots after curing → under-mixed or mis-measured
• Rapid smoking/heating in the cup → too much hardener or too large a mixed volume
• Cloudiness → moisture contamination or cold resin

Pro Tips

• Warm resin (place bottles in warm water briefly) flows and mixes better in winter.
• Mix smaller batches more often rather than one giant batch.
• Use the same cup style every time so your ratio habits stay consistent.

Need help with a specific product's mixing guidance? Contact Aurexa Resin — we support every system we supply.