Resin Calc

Deep Pour Epoxy Calculator

Sized for thick casting pours rather than surface coats. Set your product's maximum pour depth and this works out the volume, the 2:1 split and how many layers you need.

Epoxy Volume Calculator

Project Shape
Dimensions
in
in
in

Your Results

Total Epoxy Needed

585.1fl oz

APart A (Resin)

390.1fl oz

BPart B (Hardener)

195fl oz

Layers needed

2

Mix per layer

292.6fl oz

Equivalent by weight
447.6 / 193.3 oz
Cavity volume
960 in³
Mix Ratio (Resin : Hardener)
2:1

Recommended for this pour

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Deep Pour Casting Resin

Low-exotherm formula for thick single pours, commonly 2 to 4 inches per layer though some products allow less, so check your data sheet. The right choice for river tables and thick castings. Usually 2:1, though 3:1 systems exist.

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Essential mixing tools

What Makes Deep Pour Epoxy Different

Deep pour and coating epoxy are not the same product used at different thicknesses. They are different chemistries, and using the wrong one in a thick pour is the single most expensive mistake in resin work.

It cures slowly on purpose

Epoxy curing is exothermic: the reaction generates heat. In a thin film that heat escapes into the air. In a thick mass it cannot, so the centre gets hotter, which speeds the reaction, which makes more heat. Deep pour resin uses a slower system so the heat has time to dissipate.

It is usually mixed 2:1

Most deep pour casting resins take two parts resin to one part hardener by volume, against the 1:1 typical of table top epoxy. The ratio is fixed by the chemistry, so set it to match your product rather than assuming. For a channel plus its coats, the river table epoxy calculator splits the products for you.

It has a maximum pour depth

Commonly two to four inches per layer, though some products allow more and a few less. Exceeding it brings back the overheating problem the resin was formulated to avoid. Enter your figure below and the calculator splits the pour into layers for you.

It takes much longer to cure

A slow exotherm means a long wait. Deep pours frequently need several days before they can be worked, against roughly 24 hours for a coating epoxy. Rushing to demould or sand a pour that is still soft ruins the surface.

What Happens When a Pour Is Too Deep

Overheating shows up in recognisable ways, and none of them can be repaired after the fact.

Cracking

The hot centre expands and the cooler outside does not, so the casting fractures internally or splits along the wood line. This can happen hours after the pour looked fine.

Yellowing or amber patches

Excess heat discolours the resin, usually worst in the thickest section where the heat had nowhere to go. On a clear river pour it is immediately obvious and there is no way to bleach it out.

Boiling and trapped bubbles

In severe cases the mass gets hot enough to off-gas, leaving a foam of bubbles through the middle of the casting. The surface may look acceptable while the interior is ruined.

Shrinkage and pull-away

A hot cure shrinks more as it cools, which can pull the resin away from the live edge and leave a visible gap between the wood and the pour.

Deep Pour Epoxy Questions

How deep can I pour epoxy in one layer?

Deep pour casting resins are commonly rated for two to four inches per layer, while table top epoxy is usually limited to a quarter inch or less. The exact figure is on your product data sheet. Enter it in the calculator and it will tell you how many layers your depth needs.

What mix ratio is deep pour epoxy?

Most deep pour resins are 2:1 resin to hardener by volume, though 3:1 systems exist. The ratio is set by the chemistry and is not adjustable. Changing it does not slow the cure, it just prevents a proper one.

Can I use table top epoxy for a deep pour?

Not in a thick layer. Coating epoxy is formulated to cure fast, which generates too much heat in a deep mass and leads to cracking, yellowing or bubbling. You can build depth by pouring it in thin layers, which the epoxy coverage calculator will size, but a dedicated deep pour resin is simpler and avoids layer lines.

How long between deep pour layers?

Pour the next layer once the previous one has reached a firm but slightly tacky state, which gives a chemical bond rather than a mechanical one. Timing varies by product and temperature, so follow the recoat window on your data sheet.

Does temperature affect a deep pour?

Considerably. A warm workshop speeds the reaction and raises the peak temperature, making overheating more likely, while a cold one can leave the resin under-cured and soft. Most products specify a working range, commonly somewhere around 21 to 24 degrees Celsius.