Epoxy Resin Art

Epoxy resin art is the branch of resin art built on a two-part epoxy system, and for most artists it has become the default choice for pours, coatings and deep, glassy artworks. There are other resins on the market, each with loyal users, but epoxy combines clarity, toughness and a forgiving working time in a way that suits painting with liquid colour.

This guide explains why epoxy wins for most art, how the chemistry works in plain words, and why an art epoxy and a casting epoxy are not interchangeable. If you understand these basics, you will choose the right product first time and avoid a great deal of frustration at the bench.

Why epoxy resin art dominates the medium

Four families of resin show up in craft shops and studios. Here is how they compare for art:

• Epoxy: low odour compared with the alternatives, excellent adhesion, very little shrinkage, high gloss and good clarity that shows off mica powder and metallics. Cures at room temperature with a hardener. Working time ranges from minutes to hours depending on the formula.
• UV resin: a single-part resin that cures in seconds to minutes under an ultraviolet lamp. Brilliant for jewellery, small charms and quick repairs, but light cannot penetrate thick or heavily pigmented layers, so it is unsuitable for large pours.
• Polyester: the traditional casting resin, cured with a small amount of catalyst. It is inexpensive and sets hard, but it has a strong styrene smell, shrinks more and can be brittle. Mostly used by experienced casters and in fibreglass work.
• Polyurethane: fast-setting and often opaque or semi-clear, popular for mould-making, prototypes and small cast parts. It is very sensitive to moisture, which can foam the mix, and is rarely used for clear art pours.

For a piece of epoxy resin art on canvas, panel or timber, epoxy gives the longest window to manipulate colour, the best bond to the substrate and the least shrinkage, which means fewer cracks and pull-aways as it cures. It also takes pastes, inks and tints readily, as our guide on how to colour epoxy resin explains.

The chemistry in plain words

An epoxy system arrives as two bottles: Part A, the resin, and Part B, the hardener. On their own both are stable liquids. Mix them in the correct ratio and the molecules start linking together into long, cross-connected chains. Over hours and days the liquid becomes a gel, then a solid, and finally a fully cured plastic that will not melt again when warmed.

The ratio matters. The manufacturer designs the two parts to react in specific proportions, whether one to one, two to one or something else. Too much of either leaves unreacted material behind, which shows up as soft, sticky or cloudy patches that never fully harden. Measure precisely and mix thoroughly, scraping the sides and bottom of the cup.

Exotherm and working time

The reaction gives off heat, known as exotherm. In a thin layer the heat escapes into the air and you barely notice it. In a thick mass the heat builds up, which speeds the reaction, which creates more heat. That runaway effect can lead to smoking, cracking, yellowing or a rippled surface.

Working time, often called pot life, is how long the mixed material stays fluid enough to pour and manipulate. Warmth shortens it, a cool room lengthens it, and leaving the mix in a deep cup shortens it dramatically because the heat stays concentrated. Experienced artists pour mixed epoxy out of the cup and onto the surface promptly, which spreads it thin and buys time.

Art epoxy versus casting epoxy

Not all epoxies behave the same, and picking the wrong type is the most common reason a project goes wrong.

1. Art or coating epoxy is slightly thicker, self-levels into a domed layer and cures in roughly a day. It is designed for layers of a few millimetres and is ideal for cells, swipes and flood coats on panels, the methods covered in how to make epoxy resin art.
2. Casting or deep pour epoxy is thin and runny, releases air easily and cures slowly so heat can escape. It is designed for thick sections, moulds, tables and the layered 3D work found in advanced resin art techniques, but it will run off a canvas edge and takes days to harden.

Using a casting resin for a thin art pour often leaves a soft, runny result, while using an art resin in a deep mould risks overheating. Read the datasheet for maximum layer depth before you begin.

Getting the best from epoxy resin art

A few habits separate glossy, crisp results from sticky or hazy ones:

• Work at a steady room temperature, ideally around 20 to 24°C, and keep resin bottles at that temperature beforehand.
• Mix slowly for the full recommended time to avoid whipping in air.
• Pass a heat gun or torch briefly over the surface to release bubbles, keeping it moving.
• Cover the piece with a dust cover such as a clean box while it cures.
• Allow the full cure time before sanding, hanging or handling heavily.

Safety is part of the process. Uncured epoxy is a skin sensitiser, so wear nitrile gloves every time, work with good ventilation and use an organic-vapour respirator for larger pours and whenever you sand cured resin.

Because resin artists often work with their hands close to the mix, NIOSH’s booklet on preventing dermatitis when working with epoxy resins is worth a read. It is old but still relevant on avoiding skin contact, ventilation and keeping a tidy workspace.

Related guide: Resin Art Kit: Best Kits for Beginners (Buyer’s Guide)

Frequently asked questions

Can I mix UV resin and epoxy in the same artwork?

Yes, but in separate layers. Many artists use UV resin to tack small elements in place, then pour epoxy over the top once the UV layer is fully cured.

Why is my epoxy resin art still sticky after two days?

The usual causes are an inaccurate ratio, insufficient mixing or a room that is too cold. Unfortunately sticky patches rarely cure later and generally need scraping off and re-pouring.

Is epoxy better than polyester for a beginner?

For most beginners, yes. Epoxy has less odour, more working time and less shrinkage, which makes it more forgiving while you learn. Our resin art for beginners guide suggests simple first projects.

Watch epoxy in action

For a look at how we use epoxy with colour and light, visit the Go Bespoke YouTube channel, @go-bespoke, and see our builds from first pour to finished piece.

Want a piece of epoxy resin art made to your colours? Get in touch for a bespoke quote.