Building a resin river table is one of the most rewarding ways to combine natural timber with
modern epoxy. The key to a strong, clear, professional-looking result is careful preparation: dry timber, a leakproof mould, the right resin for each stage, and a controlled curing environment.
This guide brings together Paul’s practical workshop recommendations, products from Resin Wood Tables NZ and supporting tutorials from the Resin Wood Tables NZ YouTube channel.
Important: Always read the current product label, technical data sheet and safety data sheet before use. The manufacturer’s current mixing ratio, maximum pour depth, working time, temperature range and personal protective equipment requirements take priority over general advice. Wear suitable gloves and eye protection, maintain ventilation and follow the SDS for respiratory protection. Keep children, pets, flames and ignition sources out of the work area.
What You Will Need
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MDF, melamine or Form-ply for the mould
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Screws and suitable silicone sealant
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Accurate scales or measuring equipment specified for each resin
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Clamps or weights
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Spirit level
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Moisture meter
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Gloves, eye protection and any other PPE required by the SDS
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Sanding and finishing equipment
1. Plan the Table Before You Begin
Decide on the finished length, width and thickness of the tabletop, the width of the resin river and the position of the live edges. Lay the slabs out on a flat surface and experiment with their position before cutting anything.
Calculate the approximate volume of the river in litres using its average length, width and depth. Add a sensible allowance for irregular live edges, knot holes and material left in mixing containers. The Resin Wood Tables NZ resin calculator can help you estimate how much epoxy you'll need.
Plan every stage around the resin’s working and curing times. Deep pours generate heat while curing, so the correct product, pour depth, room temperature and batch size are essential.
2. Choose and Prepare the Timber
Your timber should be around 12% moisture content or lower before you encapsulate it in resin. Wet or unevenly dried wood can shrink, move, cup, crack or interfere with adhesion after the table has been poured.
Check several areas on both slabs with a moisture meter. Remove bark, loose fibres, dirt, grease and weak or rotten material. Clean and sand the live edges without removing all of their natural character. Flatten the slabs as needed, and ensure the surfaces that will sit on the mould are stable.
Although heat and clamps can sometimes correct movement after curing, prevention is far easier than repairing a completed table. Store the prepared slabs flat, in the same controlled environment where they will be poured.
3. Build a Strong, Leakproof Mould
Paul recommends starting with a good mould made from MDF, melamine or Form-ply,
because a smooth, slippery surface makes demoulding easier.
Cut the mould base and sidewalls so there is enough room around the slabs for the planned tabletop dimensions. Screw the sides securely to the base, then seal every internal seam and corner with silicone. A tiny gap can release a surprising amount of resin, so inspect the mould carefully before pouring.
Make sure the mould is sitting on a solid, perfectly level surface. Apply Blue Whale Mould Release Agent evenly as directed and allow it to become ready before inserting the timber.
Video: How to Make a Mould
4. Seal the Timber
Sealing porous timber helps reduce air release and gives later coats a more predictable
surface. Paul’s first choice is Resinzwood 2:1 Fast Set Epoxy Sealer. The current product page specifies a 2:1 mixing ratio by weight, so use accurate scales rather than assuming the same ratio by volume.
Mix Parts A and B thoroughly according to the product instructions, scraping the sides and bottom of the container. Paul’s workshop method is to add approximately 10–20% isopropyl alcohol only after Parts A and B have been completely mixed. This lowers the viscosity and can help the sealer penetrate the timber. However, only modify the product if the current manufacturer guidance permits it: isopropyl alcohol is flammable, changes the formulation and increases vapour exposure. The product page advises suitable gloves and a mask when using this method; keep all ignition sources away and follow the SDS.
Coat the top, bottom and exposed edges so moisture exchange remains as even as possible. Coating only one face can encourage cupping, bending or splitting as the untreated side absorbs or releases moisture differently.
Other sealing options include:
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Resinzwood Knot Hole Resin, particularly for filling cracks, knots and small voids
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Multi Sealer Epoxy, a lower-cost solvent-based option that requires strict attention to ventilation, vapours and recoat compatibility
Allow the sealer to reach the correct recoat or cure stage before continuing. Do not trap solvent beneath another epoxy layer.
Video: Sealing Timber Procedure
5. Decide Whether to Seal the River Edges
There are two valid approaches to the live edges that form the resin river:
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Leave the river edges unsealed: The deep-pour resin can penetrate the wood more deeply and form a strong mechanical bond. The trade-off is that escaping air may create more bubbles.
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Seal the river edges: This can reduce bubbles and make a clear river easier to control, but heavy sealing may reduce penetration into the timber.
For a solid or heavily pigmented river that will be machined flush, small bubbles are often easier to hide. For a crystal-clear river, sealing the live edges is usually the more forgiving option. Whichever method you choose, remove loose fibres and contamination so the resin bonds to solid timber.
6. Position and Secure the Slabs
Place the dry, sealed slabs in the mould and set the river width. Check that the layout is square and that the mould remains level in both directions.
Clamp or weight the timber firmly to the base. Timber can float as you add a large volume of resin, even when the slabs feel heavy. Protect the timber beneath clamps or weights and make sure nothing can shift during the pour.
Complete one final leak inspection. Confirm that all corners are silicone-sealed and keep an emergency tray, sealant and mixing container nearby.
7. Mix and Pour the Resin River
For a deep river pour, Paul recommends Ocean Cast 100 Deep Pour Epoxy, formulated for low heat build-up, de-foaming, and high UV protection.
The current product page recommends maximum river-table pours of:
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Up to 60 mm for beginners
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Up to 80 mm for experienced users
For standard Ocean Cast or any other casting resin, follow the limit on that product’s current instructions. Paul’s general recommendation for standard Ocean Cast is approximately 35–40 mm per layer. Never assume that different deep-pour epoxies share the same allowable depth.
Condition the resin and workshop to the recommended temperature before mixing. Paul recommends maintaining the room at approximately 18–23°C during curing. Provide gentle room ventilation without blowing dust or strong airflow directly over the resin.
Measure exactly by the method stated for that product—weight and volume ratios are not interchangeable. Mix slowly and thoroughly, scraping the container’s sides and bottom. Add compatible pigments sparingly and remain within the manufacturer’s maximum pigment loading.
Pour steadily into the lowest part of the river and allow the resin to find its level. Avoid introducing unnecessary air. Deal with surface bubbles only by a method approved for the resin. If using a flame, follow the product instructions, keep it moving and account for the fire risk posed by resin, solvent vapours and nearby materials.
Do not move, machine or add an incompatible layer until the resin reaches the specified cure or recoat stage.
Video series: Sea La Vie—River and Ocean Table Techniques
8. Demould, Flatten and Sand
Once the deep pour has cured sufficiently, remove the screws and carefully remove the mould walls. Do not force a still-flexible casting out of the mould.
Flatten the tabletop using a router sled, CNC machine, wide-belt sander or another suitable method. Work progressively through the sanding grits and remove all dust between stages. Before applying an epoxy flood coat, prepare the surface to the exact grit and cleaning method recommended for that coating.
Pay particular attention to scratches in clear resin. Fine scratches that seem invisible when dry can reappear beneath a clear topcoat.
9. Apply the Top Coat or Flood Coat
The flood coat protects the surface, fills fine sanding marks and creates a level, high-gloss
finish. Resin Wood Tables NZ currently offers several choices:
Ultra Fast Tabletop Epoxy
Resinzwood Ultra Fast Tabletop Epoxy is Paul’s favourite when speed and hardness are priorities. Its current specifications list a 2:1 ratio by weight, a short 10–15 minute working time, a 4–6 hour initial cure, a 24–48 hour full cure and a recommended thickness of 3–5 mm. Have the surface, tools and helpers completely ready before mixing.
Crystal Clear Tabletop Resin
Resinzwood Crystal Clear Tabletop Resin is a self-levelling, high-gloss coating mixed 2:1 by weight. It is a useful choice when you want a less rushed application than an ultra-fast system. Confirm its current working and curing times before starting.
Crekoat Flake Floor Epoxy
Crekoat Flake Floor Epoxy may also be used for suitable tabletop applications and is generally supplied in larger kits. Check availability, application thickness and finishing suitability for your particular table before purchasing.
Set the tabletop perfectly level, control dust and calculate enough resin to cover the entire surface without stopping. Mix accurately, pour promptly and spread evenly without overworking the coating. Follow the specified cure time before handling or sanding.
Video: How to Flood Coat a Tabletop
10. Finish and Fit the Legs
After the final coat has fully cured, inspect the edges and underside, remove drips and complete any required polishing. If the wood will receive oil or another finish instead of full epoxy encapsulation, confirm that it is compatible with the cured resin and follow its preparation instructions.
Mark the leg positions carefully and pre-drill all fixings. Use inserts or slotted mounting holes where appropriate so natural timber movement is not unnecessarily restricted. Large slabs may also benefit from steel stiffeners or C-channel supports.
Allow the epoxy to achieve its full stated cure before putting the table into service. Protect it from strong direct sunlight and excessive heat; UV inhibitors slow yellowing but do not make epoxy completely immune to long-term UV exposure.
Paul’s Vital River-Table Checklist
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Start with timber at approximately 12% moisture content or lower.
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Build the mould from smooth MDF, melamine or Form-ply.
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Apply mould release according to its instructions.
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Silicone-seal every mould corner and joint.
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Clamp or weight the timber so it cannot float.
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Keep the mould and tabletop perfectly level.
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Maintain gentle ventilation without airflow directly over the resin.
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Keep the curing room around 18–23°C, subject to the resin’s instructions.
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Measure each product by its stated method and ratio.
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Respect the resin’s maximum pour depth and working time.
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Keep the work area clean, dry and free from flames or ignition sources.
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Read the current label, technical data sheet and SDS before every stage.
Final Thoughts
A successful resin river table is built long before the main pour. Dry timber, careful sealing, a rigid leakproof mould, accurate mixing and temperature control will prevent most common failures. Take your time during preparation, use a resin designed for the required depth, and don't rush the curing stages.
For more product information, practical support and project inspiration, visit Resin Wood Tables NZ and subscribe to the Resin Wood Tables NZ YouTube channel.
Video Resource Sea La Vie Major Project 14 Videos
