Easy Epoxy Calc

How much epoxy for a river charcuterie board?

Short answer

You need about 0.29 gallons of mixed epoxy — roughly 37 fluid ounces — for an 18-inch river charcuterie board with a river averaging 3 inches wide and 1 inch thick, including a 15% allowance for cup residue.

How to work it out

  1. 18 in × 3 in × (1 in + 1/16 in proud) = 57.4 cu in = 31.8 fl oz
  2. + 15% waste = 0.29 gal → 1 × 0.5 gal kit
  3. Lifts: 1-1/16 in ÷ 2 in per layer → 1 lift
  4. Batches: 0.29 gal ÷ 0.5 gal (one whole kit) → 1 → A 0.76 qt (1.83 lb) + B 0.38 qt (0.77 lb) each
  5. Mix ratio 2 : 1 by volume, SG A 1.15 / B 0.97 (typical, not published by the maker — type your data sheet’s SGs for exact weights) → Part A 0.19 gal (1.83 lb) + Part B 0.1 gal (0.77 lb)

Small river boards are a good way to practise before committing to a table. An 18 in board with a 3 in river needs only a little over a quart of mixed resin, but because so little is mixed, the film left on the cup and stir stick is a bigger share of it — so this example uses a 15% allowance instead of 10%.

Adjust for your project

in
in
Measure across the gap, not the whole table — the diagram just below the calculator shows where.
in
Your slab thickness at the thickest spot. About 1/16 in extra, so you can sand it flat, is added for you (“Pour proud” under More options). Many deep-pour resins also have a minimum depth — often 2 in.
in
On the label as “max pour depth”. Not bought yet? Leave 2 in — many deep-pour epoxies allow 1–2 in per layer.
Total of both bottles together. Most “1 gallon kits” are ½ gal resin + ½ gal hardener — enter 1. If the listing says 1 gal of EACH, enter 2.
gal
Total of both bottles together. Most “1 gallon kits” are ½ gal resin + ½ gal hardener — enter 1. If the listing says 1 gal of EACH, enter 2.
More options: waste · proud · product …
%
Cup and bucket film, small leaks, the seal coat on the live edges. Use 15% for very open or punky wood.
in
Resin poured above the wood so the whole top can be sanded flat — 1/16 in is typical. Enter 0 if you already added it to the depth.
Fills in the mix ratio, weights and depth limits from the maker’s published data, and hides those fields. Always check the data sheet that comes with your batch.
in
From the label — e.g. MAS Deep Pour X 2 in, FlowCast 1/2 in
gal
Some labels lower the deepest layer for big pours, or cap the volume per layer. Enter that volume here; leave blank if your label doesn’t.
fl oz
Open knots and cracks that join the river fill up too. A rough guess is fine: a 1 × 1 × 3 in knot holds about 1.7 fl oz.
Only changes the Part A / Part B split — it’s printed on the kit. Tabletop and art resins are usually 1:1; deep pour often 2:1.
From the TDS, in g/ml. Leave blank for 1.15 (typical, not published by the maker).
From the TDS, in g/ml. Leave blank for 0.95 on 1:1 kits or 0.97 on other ratios (typical, not published by the maker).
gal
Resin + hardener mixed in one bucket. Leave blank to mix one whole kit at a time; enter less (1.5 gal or 6 L is easy with a drill paddle) to split each lift into batches you pour back to back.
From the label: when the next layer can go on (the recoat window) at room temperature. Leave blank to skip the pour schedule.
From the label: how long after the last pour before the table can come out of the form.
$
Optional — your kit price, for a cost estimate
Deep-pour epoxy to buy0.29 gal1.14 qt · 1.08 L
In short
Buy 1 × 0.5 gal deep-pour kit. Pour the river in one layer.
What the resin will weigh in the table (for the form and legs)
2.28 lb (1.03 kg)
Left over from the last kit
0.21 gal (0.86 qt · 0.81 L)
Mixing details: batches, Part A and Part B
Mixing details: batches, Part A and Part B
Part A (resin)Part B (hardener)
Whole job24.4 fl oz · 1.83 lb12.2 fl oz · 0.77 lb
  • What to buy: 1 × 0.5 gal deep-pour epoxy kit. Each kit has both bottles (resin + hardener) — you don’t buy them separately.
  • Check the label’s minimum depth too. Many deep-pour resins list a minimum pour as well as a maximum — MAS Deep Pour X, for one, wants at least 2 in, and thinner pours cure slowly or stay soft. At 1-1/16 in, choose a resin whose range includes that depth, and type its minimum under Min depth per pour (More options) to check.
  • Seal the live edges and any bark with a thin coat first — dry wood soaks up epoxy and releases bubbles into the pour.
  • About 27.4 fl oz will be left in the jugs. Kept sealed, it fills knots and cracks later, or makes a practice river board.

For this job · affiliate link
Deep pour epoxy kitYou need 0.29 gal — 1 × 0.5 gal kit. Pick one whose label range includes 1-1/16 in per pour — the minimum as well as the maximum; a tabletop resin would overheat at 1 in deep.
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Epoxy by board length (3 in river, 1 in thick, 15% waste)

Epoxy by board length (3 in river, 1 in thick, 15% waste)
Board lengthDeep-pour epoxy to buyKits to buy
12 in24.4 fl oz1 kit
14 in28.4 fl oz1 kit
16 in0.25 gal1 kit
18 in0.29 gal1 kit
20 in0.32 gal1 kit
24 in0.38 gal1 kit

What to know about a river charcuterie board

Size and thickness. Serving boards are commonly 14–20 in long and 8–12 in wide, and about 3/4–1 in thick after flattening. A 1 in pour — 1 1/16 in with the bit poured proud for sanding — is shallow for some deep-pour resins; a few list a 2 in minimum. Put your resin’s minimum in Min depth per pour and the calculator warns you, or choose a casting resin whose label includes 1 in in its range. Otherwise it may stay soft for days.

Kit fit. You need about 37 fluid ounces with waste. A quart kit (32 fl oz) is short, so the calculator calls for two; a half-gallon kit — entered under Another size, since it is smaller than the usual table kits — leaves about 0.21 gallons (roughly 27 fl oz) spare, enough for a second board. With batches this small, measure carefully: a 2:1 product eyeballed in a small cup can be off by more than the whole waste allowance. Graduated mixing cups, or a digital scale and the Part A and Part B weights shown above, make it repeatable.

Food contact. Check the cured resin’s food-contact statement on the label or data sheet before serving on it, and treat the piece as a serving board rather than a cutting board — knife scores in the resin collect food and are hard to clean.

Leftover from a table pour often covers one of these. The spare jug from How much epoxy for a river coffee table is more than enough, and the 7.57 L left from two 12 L kits in How much epoxy for a 180 cm river table would cover several boards.

Different size? Use the full River Table Epoxy Calculator.

What you’ll need

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Frequently asked questions

How much epoxy for a charcuterie board with a 4 inch river?

About 0.38 gallons (roughly 49 fl oz) for an 18 in board, 1 in thick, with 15% waste.

How much epoxy for a 3/4 inch thick river charcuterie board?

About 28 fluid ounces for an 18 in board with a 3 in river, including 15% waste and 1/16 in poured proud.

Is one quart of epoxy enough for a river charcuterie board?

Not quite. With 15% waste you need 0.29 gal (about 37 fl oz), more than a 32 fl oz quart, so plan on 2 kits of 1 qt — or trim the allowance and scrape the cup well.

Other common sizes

Sources