Casting Resin Guide

Choosing the Right Casting Resin for Your Project

Resin art opens up endless opportunities to create unique pieces, from jewellery and home décor to dramatic river tables. But with so many resin systems available, how do you know which one to choose? The key lies in understanding slow curing, fast set, and deep pour resins and when to use each.

What Are The Benefits Of Slow Curing Casting Epoxy Resins?

When should you choose a slow curing resin instead of something faster? The answer usually comes down to project size and durability. For larger castings, such as river tables, lamp bases, or intricate moulds,slow curing systems like Just Resin’s ArtCast Slow are ideal.

One of the biggest advantages of a slow cure is the longer pot life (around 30–40 minutes). This gives you extra working time to mix pigments thoroughly, remove bubbles, or carefully place inclusions before the resin begins to set. Slow resins also cure with far less exotherm (heat build-up), which reduces the risk of cracking or warping in larger pours.

Of course, the trade-off is time. Slow resins can take up to 7 days to fully cure, with demoulding often not recommended until after 24–48 hours. But that patience pays off. ArtCast Slow cures to a high Shore D hardness (85–90), making it extremely tough and durable. That’s why it’s often chosen for castings that will see daily use, such as keychains, ornaments, and functional art pieces.

If your project requires strength, clarity, and the ability to work without rushing, a slow cure system will deliver a professional, glass-like result.

Why Should I Use a Fast Set Casting Resin?

What if you don’t want to wait a whole week before demoulding? That’s where a fast set resin comes in handy. For smaller moulds, quick turnaround jobs, or projects that need to be ready in just a day or two, Just Resin’s ArtCast Fast is the perfect option.

With a much shorter pot life (around 15–20 minutes) and a cure time that allows for demoulding in 12–24 hours, ArtCast Fast gives you speed without sacrificing clarity. This makes it ideal for smaller projects like jewellery, charms, and detailed moulds, where you want to keep the creative process moving quickly.

Another benefit is that fast curing resins are less prone to yellowing over time, thanks to their advanced UV-stabilised formulas. They also have a naturally low viscosity, which means they flow easily into tight moulds, thin layers, and detailed designs, perfect for capturing intricate textures without trapping bubbles.

Fast set casting resin is also incredibly durable. Once cured, it can be sanded, drilled, and polished just like a slow curing system, but with the added advantage of getting your finished piece in your hands sooner. If you’re an artist who thrives on quick results, or you’re producing resin crafts in higher volume, fast set resin is the time-saving solution.

When Should I Use a Deep Pour Casting Resin?

Not all projects are created equal when it comes to resin. While ArtCast Fast and Slow are excellent for smaller moulds, jewellery, or detailed pieces, they aren’t always the best choice when you want to work on something big, bold, and deep , like a river table, large encapsulations, or thick furniture designs. That’s where RiverPour Deep Pour Epoxy Resin comes into play.

RiverPour is designed specifically for deep castings up to 50 mm in a single pour. Unlike standard casting resins, which may overheat or cure unevenly if poured too thick, RiverPour has a unique low-exotherm formulation. This means it cures steadily, staying crystal clear without cracking or yellowing. It also gives you a much longer working time—over 4 hours—so you can take your time mixing pigments, placing inclusions, or creating dramatic depth effects without feeling rushed.

If you’ve ever dreamed of creating a statement river table or a thick resin-and-wood design, RiverPour is made for the job. Its 2:1 mix ratio by weight makes measuring simple and accurate, even in big batches. It self-levels beautifully, releases bubbles with ease, and cures to a hard Shore D 78–82 finish—strong enough for sanding, machining, and everyday use once fully cured.

A common question artists ask is: “How long will it take before I can demould?” With RiverPour, you’re generally looking at 36–48 hours before demoulding, with full cure achieved in around 7–10 days. That balance of depth capacity, clarity, and durability is why it’s the go-to resin for professional river table makers and hobbyists who want flawless results on a bigger scale.

And yes—you can absolutely use RiverPour for artistic embeds too. Larger natural objects, ocean scenes, or layered pours look incredible with the depth and clarity RiverPour provides.

Beautiful Things That You Can Cast In Resin

When creating resin art, a little creativity goes a long way. Embedding objects in resin can transform everyday items into timeless keepsakes or striking décor. The fun part is that you can use almost anything as a mould or inclusion, flowers, seashells, pebbles, beads, even tiny toys. But the real secret lies in choosing the right resin for the right embed.

• Small and detailed objects: For pendants, charms, or mini keepsakes, a fast set resin like ArtCast Fast is ideal. It flows easily into fine details and gives you finished results in as little as a day. Think dried flowers in jewellery, beads, or even glitter effects.

• Medium-sized castings that need durability: If you’re creating slightly larger pieces such as pyramids, keychains, or memorial keepsakes with ashes or hair, ArtCast Slow offers the time and toughness you need. The slower cure allows bubbles to escape naturally, leaving a flawless, glassy finish.

• Large-scale or deep projects: When you’re aiming for dramatic depth, such as river tables, ocean scenes, or encapsulating driftwood or shells, RiverPour Deep Pour Resin is unmatched. Its ability to cure thick layers without overheating ensures your inclusions stay perfectly suspended and crystal clear.

So whether you’re preserving a delicate flower in a pendant, capturing a meaningful object in a keepsake, or building a show-stopping river table, there’s a resin designed to suit your project. By matching the resin system to the scale and detail of your creation, you’ll achieve not only stunning clarity but also the durability to ensure your work lasts for years to come.