Perfect Resin Mixing: Step-by-Step Technique Guide

Understanding Resin Ratios

The foundation of perfect resin mixing is the correct ratio of resin to hardener. Get this right, and everything else falls into place. Get it wrong, and your project fails.

Most Common Ratios

Ratio	Resin : Hardener	Most Common Brands	Cure Time	Notes
1:1	Equal parts by volume or weight	ArtResin, Puduo	24 hours	Easiest to measure. Most beginner-friendly.
2:1	2 parts resin : 1 part hardener	EasyCast, ACP	24-48 hours	Requires more precise measurement.
3:1	3 parts resin : 1 part hardener	Some specialty resins	24-48 hours	Rarely used. Very specific applications.

CRITICAL: Always check YOUR specific resin's instructions. Different brands have different ratios. Using the wrong ratio is the #1 cause of sticky, uncured resin.

Never guess or assume. If you've lost the instructions, look up your brand online or contact the manufacturer. It takes 2 minutes and saves your project.

Measurement Methods: Choose Your Approach

You can measure by volume (cups, markings) or by weight (scale). Both work—choose what fits your workflow:

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Volume Measurement

Use markings on silicone cups or measuring containers. Good for casual mixing. Less precise but faster. Works great if you're consistent.

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Weight Measurement

Use a digital scale (grams). Most precise method. Best for 1:1 ratios. Takes 30 seconds more but guarantees accuracy. Recommended for serious crafters.

Measuring Tips for Accuracy

✓ Use Same Container: If using volume, always use the same cup. This ensures consistency cup-to-cup.
✓ Tare the Scale: If weighing, tare (reset to zero) between resin and hardener for accuracy.
✓ Measure on Level Surface: Keep measuring cup level. Angled measurements are inaccurate.
✓ Read at Eye Level: When checking volume markings, view from eye level, not from above.
✓ Don't Mix in Original Bottles: Always mix in a separate container. Never mix directly in resin or hardener bottles.

Best practice: Use weight measurement with a digital scale for perfect 1:1 ratio resins. It's foolproof and takes minimal extra time.

Step-by-Step Mixing Technique

Follow this exact process every time for consistent, perfect results:

Complete Mixing Protocol

1

Prepare Your Container

Use a clean silicone or plastic cup. Never reuse containers with dried resin residue (causes cloudiness). Clean cups are essential.

2

Measure Resin First

Pour resin into your clean container first. If using weight: place cup on scale, tare to zero, pour resin to desired weight. If using volume: pour to your marked line.

3

Measure Hardener Second

Add hardener to resin. Using weight: tare scale again, add hardener to correct amount. Using volume: pour hardener to marked line in same cup. Ratios are critical.

4

Initial Visual Mix (5 seconds)

Before stirring, observe the mix. You should see two distinct colors layered. This confirms both components are present. If you only see one color, check your measurements.

5

Stir SLOWLY (2-3 minutes)

Use a stirring stick and mix SLOWLY. This is critical—slow mixing minimizes air bubble creation. Stir continuously but gently for 2-3 full minutes. Don't rush this step.

6

Scrape Sides and Bottom

After 1.5 minutes, scrape sides and bottom of cup with stirring stick. Make sure all components are mixed, especially corners where unmixed material hides.

7

Continue Slow Stirring

Stir for remaining 1-1.5 minutes, continuing to scrape sides. Mixture should become uniform in color with no streaks. Uniform color = properly mixed.

8

Visual Confirmation

When complete, mixture should be completely uniform color, no stripes or layers visible. If you see any streaks, stir for additional 30 seconds and check again.

9

Let Rest (30 seconds to 1 minute)

After mixing, let the cup sit undisturbed for 30-60 seconds. This allows large air bubbles created during mixing to rise to the surface (you'll see them).

10

Ready to Pour

After rest period, your resin is ready to pour into molds. If using heat gun for bubble removal, wait until after the rest period.

Timing Note: After mixing, your resin has a "pot life"—typically 30-60 minutes before it becomes too thick to pour. Work efficiently but don't rush.

Preventing Air Bubbles While Mixing

Most air bubbles come from mixing technique. Prevention is far easier than removal:

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Slow Mixing Speed

Mix slowly (not fast). Fast mixing whips air into the resin. Slow, deliberate mixing minimizes air incorporation. Take the full 2-3 minutes.

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Stir Vertically

Use vertical stirring motions (up and down) rather than circular. Circular motions create more swirling and air. Vertical motion is gentler.

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Scrape Container Sides

Scrape sides and bottom throughout mixing. Unmixed material hides in corners. Scraping ensures complete mixing without extra stirring.

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Let Rest After Mixing

After mixing, let the cup sit for 30-60 seconds. This allows mixed-in air bubbles to float to the surface where you can see them.

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Cold Resin = Fewer Bubbles

Resin at room temperature (slightly cool) incorporates fewer air bubbles than warm resin. Store resin at 65-70°F if possible.

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No Vigorous Mixing

Never use power tools, electric mixers, or vigorous hand mixing. These create excessive air. Slow hand-stirring is best.

Troubleshooting Mixing Problems

❌ Streaky Mix (Not Fully Combined)

Stir for additional 1-2 minutes while scraping sides. Stop only when color is completely uniform with zero streaks. Incomplete mixing causes sticky, uncured resin.

❌ Too Many Bubbles While Mixing

You're mixing too fast. Slow down. Use gentle vertical stirring instead of vigorous circular motions. Slower = fewer bubbles. Let rest 1-2 minutes after mixing to allow bubbles to rise.

❌ Resin Too Thick to Pour

Your pot life has passed. This happens if you waited too long after mixing. Work faster next time. Once mixed, pour within 30-60 minutes depending on brand. Some brands have additives to extend pot life.

❌ Resin Sticky After 24 Hours

You likely used the wrong ratio or didn't mix thoroughly. Check your brand's exact ratio. Verify you stirred for full 2-3 minutes and mixture was completely uniform before pouring.

❌ Resin Cloudy After Curing

Could be air bubbles (stir slower next time) or moisture (work in dry environment). Could also be leftover residue in mixing cup. Always use clean cups.

❌ One Batch Cures, Next Doesn't

Temperature difference. Resin cures better at 70-75°F. Cold batches cure slower or incompletely. Keep your workspace warm and consistent.

Frequently Asked Questions

Do I need an expensive scale, or will any scale work? +

Any digital kitchen scale works fine. You need one that measures in grams and shows decimal places (like 100.5g). Must be accurate to at least 1 gram. Amazon scales for $10-15 are perfect. No need for expensive lab scales.

Can I mix in glass containers or does it have to be plastic/silicone? +

Glass works fine and is actually great—you can see the mixture clearly. Plastic and silicone work too. Avoid metal (can cause reactions). Glass is great because you can see color uniformity clearly.

How long can I wait after mixing before pouring? +

Depends on your resin brand. Most have 30-60 minute "pot life" after mixing. Check your instructions. As time passes, resin gets thicker and harder to pour. Plan to pour within 30-45 minutes to be safe.

Is it okay to mix different resin brands? +

Not recommended. Different brands have different ratios, cure times, and formulations. Mixing brands can result in improper cure, sticky resin, or cloudiness. Use one brand per project.

Can I save leftover mixed resin for later? +

No. Once mixed, the chemical reaction begins. You can't stop it or pause it. Mixed resin must be poured within 30-60 minutes. Never try to save mixed resin—it will harden in the cup and be unusable.

Should I add colorant before or after mixing? +

Add colorant AFTER mixing resin and hardener completely. Mix resin + hardener first (2-3 minutes), then add tiny amount of pigment (toothpick dab), then stir additional 30-45 seconds. Adding during mixing makes complete mixing harder.

Is there a way to fix a batch if I mess up the ratio? +

Not really. If you realize mid-mix that your ratio was wrong, you can try adding the correct amount of missing component and mixing again, but results may be unpredictable. Better to start over with fresh materials. That's why measuring carefully is critical.

Pre-Mixing Checklist

Before You Mix, Verify:

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Check brand instructions for correct ratio (1:1, 2:1, etc.)

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Have clean mixing container (no dried resin residue)

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Scale or measuring cup ready for accurate measurement

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Stirring stick prepared (wooden or silicone)

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Molds ready and placed where you'll pour

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Work surface protected with mat or plastic

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Timer ready (or keep watch on time)

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PPE on (gloves, mask, eye protection)

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Ventilation running (fan, windows open)

Perfect Resin Mixing: Master the Technique