Deep Pour Epoxy: Complete Guide and Tutorial
Updated 9 October 2026
Deep pour epoxy is the resin that makes thick, glass-clear castings possible: river tables, resin blocks, encased objects and the deep channels that carry fibre optic strands through a table top. Unlike a coating resin, which is designed to sit a few millimetres thick, a deep pour system is formulated to cure slowly, release its heat gently and stay clear through several centimetres in a single layer. This guide explains what makes deep pour epoxy resin different, how to choose one, and then walks through a full pour from mould to final cure.
At Go Bespoke, a small London workshop building resin and fibre optic tables, deep pours are the backbone of most projects. The technique is not difficult, but it is unforgiving of shortcuts. If you have only ever poured thin coats, read our main guide on how to pour epoxy resin first, then come back here for the deep work.
What is deep pour epoxy?
All epoxy cures through a chemical reaction between resin and hardener, and that reaction gives off heat (the exotherm). In a thin coat the heat escapes into the air. In a thick mass it builds up, and because heat speeds up the reaction, a fast resin poured too deep can overheat, crack, yellow or even smoke.
Deep pour epoxy resins, sometimes sold as casting resins, solve this with a much slower hardener and a lower viscosity. The result is:
- Greater depth per layer. Typically somewhere between 2 cm and 10 cm per pour depending on the product, compared with around 3–6 mm for a table top coating epoxy.
- Long working time. Often 40 minutes to several hours, which helps bubbles rise out on their own.
- Slow cure. Demoulding usually takes 3–7 days, and full hardness can take longer still.
- Thin, water-like flow. It seeps into gaps, which is why mould sealing and timber sealing matter so much.
The trade-off is that deep pour resin is softer and less scratch resistant on the surface than a coating resin, and it is not designed to self-level into a thin finish coat. Most tables therefore use a deep pour for the body and a separate flood coat or oil finish on top.
Choosing the best deep pour epoxy for your project
Searching for the best deep pour epoxy brings up a long list of brands, and most reputable products work well when used within their limits. Rather than chasing a name, compare the datasheets on these points:
| Specification | Why it matters |
|---|---|
| Maximum pour depth per layer | Decides how many layers your project needs and how safe each pour is. |
| Maximum mass or volume per pour | A compact block runs hotter than a long, narrow river of the same depth. |
| Mix ratio (by weight or volume) | Weigh-ratio systems are more accurate on large batches; never swap methods. |
| Working time and demould time | Longer working time means fewer bubbles but more waiting. |
| UV stabilisers and clarity | Important for clear river tables, less so for heavily pigmented pours. |
| Recommended temperature range | Most systems want roughly 20–25°C for the resin, mould and room. |
For river tables specifically, look for a resin rated for at least the full depth of your river in two or three layers, with good UV resistance. Our comparison of the best epoxy for river tables goes into more detail, and the guide to UV resistant epoxy resin explains why clarity fades over time and what slows it down. As for the cheapest deep pour epoxy: budget resins can work, but the savings are small compared with the cost of timber and a ruined cast, so price should be the last factor rather than the first.
Planning a deep pour: volume, layers and mould
Before mixing anything, work out three numbers: total volume, safe depth per layer and number of layers. Measure the cavity length, width and depth, then use our epoxy calculator and quantity guide to convert that into litres. Add around 10% for spillage, leakage and what stays in the mixing buckets.
Next, divide the total depth by a layer depth comfortably below the manufacturer’s maximum. If a resin is rated to 5 cm and your river is 5 cm deep, two layers of 2.5 cm are a safer plan than a single full-depth pour, particularly in a warm room or a wide, compact cavity.
The mould needs to be flat, level and completely sealed. Melamine-faced board lined with sheathing tape or a release film, with all inside corners run with silicone or hot glue, is the usual workshop approach. Deep pour resin finds pinholes that a coating resin would never reach, so test the seal before you commit a large batch.
Deep pour epoxy tutorial: step by step
1. Prepare the timber
Wood should be dry, stable and free of loose bark and soft rot. Porous end grain and live edges release air for hours once covered in resin, which is the main source of bubble trails in deep pours. Seal all surfaces that will touch the resin with a thin coat of epoxy and let it cure to tacky first; our article on the epoxy sealer for wood covers this step in full. Screw or clamp the slabs down so they cannot float when the mould fills.
2. Condition everything
Keep resin, hardener, mould and timber in the workshop for at least 24 hours so they all start at the same temperature, within the range on the datasheet. Cold resin is thick and traps air; warm resin shortens working time and raises peak temperature. Raise the mould off a cold concrete floor.
3. Measure and mix
Weigh or measure exactly as the manufacturer specifies. Mix slowly for the full recommended time, typically 3–5 minutes, scraping the sides and base of the container. For large volumes, mix in several manageable batches rather than one huge bucket: a big mass of mixed resin sitting in a container heats up faster than the same resin spread out in a mould. If you are adding colour, see how to colour epoxy resin and keep pigment to a few percent of the mix.
4. Pour
Pour steadily from a low height into the deepest point and let the resin travel on its own. Watch the edges and seams closely for the first half hour; a slow leak can drain a surprising amount overnight. Pass a heat gun or small torch lightly over the surface to release surface bubbles, keeping it moving.
5. Manage the exotherm
Over the first several hours, check the mould sides by hand. Warm is normal; too hot to keep your hand on is a warning sign. Never cover the mould with insulation, keep air moving around the room (not directly over the surface) and keep the room within the recommended temperature range throughout.
6. Time the next layer
Follow the recoat window on the datasheet. Pour the next layer too early and the heat of both layers adds up; too late and the surface is fully hard, giving a weaker mechanical bond and sometimes a faint line. If you miss the window, scuff the cured surface with 120–180 grit, remove every trace of dust, and pour onto that abraded face.
7. Cure, demould and finish
Leave the final layer for the full demould time, then longer before machining. A cast that feels hard after two days may still gum up on a router sled. Once cured, flatten, sand through the grits and finish; our guide on how to polish epoxy resin takes it from sanding to a deep gloss. For the full table workflow, the river table build guide picks up from here.
Common deep pour epoxy mistakes
- Pouring past the layer limit to save time, the commonest cause of cracking and yellowing.
- Skipping the seal coat on porous timber, leading to streams of bubbles rising for hours.
- A cold workshop overnight, causing cloudy or soft patches.
- Mixing too fast with a paddle on a high-speed drill, whipping in fine air.
- Demoulding early and flexing a cast that has not reached full strength.
Safety
Work in a well ventilated space, wear nitrile gloves, long sleeves and eye protection, and use a respirator with organic vapour cartridges for large pours or poor airflow. When sanding cured resin, wear a dust mask rated for fine particles. Never dispose of a large batch of mixed, uncured resin in a bin: let it cure in an open container somewhere safe first, as it can get very hot.
Top 10 most-watched on YouTube
Video 1 of 10 — one of the most-viewed YouTube videos for “deep pour epoxy: complete guide and tutorial”: Fire + Epoxy by Blacktail Studio (32,804,615 views as of 13 October 2026).
Thick pours concentrate the heat that resin gives off as it cures. MIT’s Plasma Science and Fusion Center publishes a clear guide to epoxy hazards and safe handling, covering heat build-up in larger batches, sensitisation, protective equipment and why partially cured resin should not be sanded.
Watch it being made
Watch our first light-up resin table being made in the workshop, with dragons and creatures appearing in the resin art, and the colours, pours and finishing shown step by step.
Resin Art Dragons and creatures in resin art table My First Light-Up Resin Table. More builds on the Go Bespoke YouTube channel.
Frequently asked questions
How deep can you pour deep pour epoxy in one layer?
It depends on the product. Many deep pour epoxy resins are rated between 2 cm and 10 cm per layer, with some specialist casting resins going deeper in cool conditions. Always use the figure on the technical datasheet and stay a little below it.
How long does deep pour epoxy take to cure?
Typically 24–72 hours to become firm and 3–7 days before demoulding, with full hardness taking longer. Cooler rooms slow this further.
Can I use deep pour epoxy as a top coat?
It is not ideal. Deep pour resin is softer and does not self-level into a thin, hard finish as well as a coating resin. Use a table top or bar top epoxy for a flood coat, or finish the sanded surface with a hard wax oil or polish.
What is the best deep pour epoxy for river tables?
Choose a clear, UV-stabilised resin whose layer depth suits your river in two or three pours, ideally with a weight-based mix ratio for accuracy on large batches.
Why did my deep pour crack or turn yellow?
Almost always too much heat: a layer poured too deep, too large a mass at once, or a room that was too warm. Thinner layers and a stable temperature prevent it.
Want to see deep pours in action? We film our builds from mould to final polish on the Go Bespoke YouTube channel, and you can explore more projects in our resin table guide.
