Every epoxy resin has a specific mixing ratio that must be followed exactly. If the proportions are incorrect, the resin may remain soft, rubbery or sticky even after several days.

If there is too little hardener, the chemical reaction cannot complete and the resin will stay sticky or soft. If there is too much hardener, the resin will not cure faster — instead it may turn yellow, overheat, or form bubbles during curing.

This is why it is important to always follow the ratio recommended by the manufacturer. For example, Artline epoxy resins use different mixing ratios depending on the formula:

• Artline Crystal Resin — 2:1 (by weight)
• Artline Honey Resin — 2:1 (by weight)
• Artline Extra Honey Resin — 2:1 (by weight)
• Artline WoodPro Deep Pour Resin — 3:1 (by weight)

If your epoxy resin is still sticky, don’t panic. This is one of the most common issues beginners encounter when working with resin, and in most cases the cause is easy to identify.

In this guide we’ll explain:

• why epoxy resin stays sticky
• the most common curing mistakes
• how to fix sticky resin
• how to prevent curing problems in the future

Why Epoxy Resin Needs Two Components

Epoxy resin always consists of two parts:

• Resin (Part A)

• Hardener (Part B)

When these components are mixed in the correct ratio, a chemical reaction begins that gradually turns the liquid mixture into a solid material.

If something interrupts this reaction, the resin cannot cure properly and may remain soft or sticky instead of becoming hard.

5 Common Reasons Epoxy Resin Does Not Cure

1. Incorrect Resin Ratio

The most common reason epoxy resin stays sticky is incorrect proportions of resin and hardener.

Many beginners assume that adding more hardener will make the resin cure faster. In reality, changing the ratio prevents the resin from curing properly.

Every epoxy resin has a specific mixing ratio that must be followed exactly. If the proportions are incorrect, the resin may remain soft, rubbery or sticky even after several days.

2. Resin Was Not Mixed Long Enough

Even when the ratio is correct, insufficient mixing can cause uncured areas.

Resin and hardener must be blended thoroughly so the chemical reaction occurs evenly throughout the mixture.

Proper mixing technique

Mix resin for at least 3–4 minutes, making sure to:

• scrape the sides of the mixing cup

• scrape the bottom of the container

• stir slowly to avoid introducing bubbles

Unmixed material stuck to the sides of the cup can cause sticky spots in your project.

3. Moisture or Dirty Tools

Epoxy resin is sensitive to moisture. High humidity can interfere with the curing process and may cause surface problems such as cloudiness, amine blush, or sticky spots.

Moisture can enter the mixture from the environment or from contaminated tools and containers. Even small amounts of water, dust, or grease can affect the chemical reaction and prevent the resin from curing properly.

To avoid these issues, always use clean, dry mixing containers and tools, and work in a controlled environment whenever possible.

Humidity levels also play an important role. Different epoxy resins perform best within certain humidity ranges.
For example, recommended working conditions for Artline resins are:

• Artline Crystal Resin and Artline WoodPro — up to 60% humidity
• Artline Honey Resin — ideally 30–40% humidity
• Artline Extra Honey Resin — below 30% humidity

Working within these ranges helps ensure proper curing and prevents common surface defects.

4. Temperature Is Too Low

Temperature plays a crucial role in how epoxy resin cures. If the room is too cold, the chemical reaction slows down significantly, and the resin may remain soft, rubbery or sticky for a long time.

For best results, Artline epoxy resins should be used at a room temperature of around 22–24 °C. This range allows the resin and hardener to react properly and ensures stable curing.

Small pours can be especially sensitive to low temperatures. If the amount of resin is very small (for example up to 150 g) or the layer is very thin, the reaction generates less internal heat and curing can slow down.

In these situations we recommend:

• warming the resin slightly before mixing (for example by placing the bottles in warm water)
• increasing the room temperature a few degrees to support the curing process

Maintaining stable working conditions is one of the easiest ways to avoid curing problems with epoxy resin.

Recommended Conditions for Artline Epoxy Resins

For the most stable curing results, epoxy resin should be used in controlled environmental conditions. For Artline epoxy resins, we recommend maintaining a room temperature of 22–24°C (71–75°F).

Humidity requirements depend on the viscosity of the resin:

• Artline Crystal Resin — up to 60% humidity
• Artline WoodPro Deep Pour Resin — up to 60% humidity
• Artline Honey Resin — ideally 30–40% humidity
• Artline Extra Honey Resin — below 30% humidity

Thicker resins are more sensitive to environmental conditions. Keeping humidity within these ranges helps prevent common issues such as surface defects, cloudiness, or incomplete curing.

Maintaining stable temperature and humidity is one of the most important factors for achieving a clear, fully cured epoxy surface.

5. Mixing Resin and Hardener From Different Brands

Resin and hardener from different brands should never be combined.

Each resin product is designed so that its resin and hardener work together in a specific ratio. Mixing components from different products usually results in curing problems. Always use the resin and hardener that belong to the same kit.

How to Fix Sticky Epoxy Resin

If epoxy resin remains sticky after several days, it usually will not cure on its own. The affected area needs to be repaired.

Remove uncured resin

Use a scraper or spatula to remove as much soft or liquid resin as possible.

Fill the area

If scraping leaves dents or holes, fill the area with fresh properly mixed epoxy resin.

Sand the surface

Once the repair has cured, lightly sand the surface so the new layer adheres properly.

Apply a new resin coat

Pour a new thin coat of epoxy resin to restore the smooth glossy finish.

Artline Epoxy Resins: Mixing Ratio, Pour Thickness and Curing Time

Different epoxy resins are designed for different types of projects.
Viscosity, curing speed and maximum pour thickness all affect how the resin behaves during the curing process.

Choosing the right resin and following the recommended parameters helps ensure stable curing and professional results.

Artline Crystal Epoxy Resin

Artline Crystal is a very clear, low-viscosity epoxy resin designed for projects where clarity and smooth self-leveling are important.

Recommended for:

• resin art

• jewelry

• molds

• coating surfaces

Technical guidelines

• Mixing ratio: 2:1 by weight

• Recommended pour thickness: up to 5 mm per layer

• Initial curing time: 12–24 hours

• Full cure: about 72 hours

Because of its low viscosity, Crystal releases bubbles easily and produces a perfectly transparent finish.

Artline Honey Epoxy Resin

Artline Honey is a medium-high viscosity resin that allows pigments and decorative elements to stay suspended in the resin.

Recommended for:

• layered resin art

• decorative pours

• artistic techniques

Technical guidelines

• Mixing ratio: 2:1 by weight

• Recommended pour thickness: up to 5 mm per layer

• Initial curing time: 18–24 hours

• Full cure: about 72 hours

Honey resin is widely used for creative resin art projects because it balances viscosity and working time.

Artline Extra Honey Epoxy Resin

Extra Honey is a very thick epoxy resin designed for techniques that require strong viscosity.

Recommended for:

• ocean wave effects

• textured resin art

• sculptural resin techniques

Technical guidelines

• Mixing ratio: 2:1 by weight

• Recommended pour thickness: 2–5 mm per layer

• Initial curing time: about 24 hours

• Full cure: 72 hours or longer depending on temperature

Its high viscosity allows artists to create dynamic textures and wave effects that would not be possible with thinner resins.

Artline Wood Pro Deep Pour Resin

Wood Pro is a deep casting epoxy resin specifically developed for large and thick pours.

Recommended for:

• river tables

• wood slabs

• deep casting projects

Technical guidelines

• Mixing ratio: 3:1 by weight

• Recommended pour thickness: up to 4–6 cm per pour depending on conditions

• Initial curing time: 48–72 hours

• Full cure: 5–7 days

Deep casting resins cure more slowly in order to control heat buildup and prevent cracking during thick pours.

Perfect Resin Starts With the Right Conditions

Most curing problems come down to just a few factors:

• incorrect mixing ratio

• insufficient mixing

• moisture or contamination

• temperature that is too low

• pouring layers that are too thick

When resin is measured accurately, mixed thoroughly and poured within recommended limits, it cures into a strong, crystal-clear surface with professional results.

Choosing the right epoxy resin for your project — such as Artline Crystal, Honey, Extra Honey or Wood Pro — makes the process much more predictable and reliable.

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