Easy Epoxy Calc

How much epoxy for a bottle cap bar top?

Short answer

You need about 2.8 gallons of tabletop epoxy for an 8 ft × 20 in bottle cap bar top with the caps laid open side down: 1.56 gallons to fill 3/8 inch deep over the caps, 1.12 gallons for a final 1/8 inch flood coat and 14.9 fl oz of edge drips, with 5% for the bucket.

How to work it out

  1. Top: 8 ft × 20 in = 13.3 sq ft; coated edges: 11.3 ft, 1.5 in tall
  2. Fill (3/8 in (yours)): 13.3 sq ft × (3/8 in − 78.5% × 1/4 in for the caps) = 1.49 gal + 5% waste = 1.56 gal
  3. Flood coat: 13.3 sq ft × 1/8 in × 1 = 1.04 gal + edge film 11.3 ft × 1.5 in × 1/32 in × 1 = 3.53 fl oz → + 5% waste = 1.12 gal
  4. Edge drips: 11.3 ft at 1.25 fl oz per foot of edge per 1/8 in coat × 1 = 14.2 fl oz → + 5% waste = 14.9 fl oz
  5. Total: 1.56 gal + 1.12 gal + 14.9 fl oz = 2.8 gal → 3 × 1 gal kits
  6. Mix ratio 1 : 1 by volume, SG A 1.15 / B 0.95 (typical, not published by the maker — type your data sheet’s SGs for exact weights) → Part A 1.4 gal (13.4 lb) + Part B 1.4 gal (11.1 lb)

Bottle caps are the thirstiest embedded bar top: crown caps stand about 1/4 in tall, so the fill needs to be around 3/8 in to bury them. That’s more than most tabletop epoxies should take in one pour, so expect two or three layers — or a product rated for thicker pours.

Adjust for your project

ft
in
Measure the top surface, including any overhang.
The edges the resin runs over. Each one gets a thin coat and drips for a while, so both are counted.
in
How tall the edge is — usually the thickness of the top.
Items buried in a clear fill pour. Solid items take up room, so they reduce the resin a little.
in
Leave blank for your tallest item plus 1/8 in of cover: 3/16 in over pennies, 3/8 in over bottle caps. Or type your own.
sq ft
Leave blank if the items cover the whole bar. If they sit in one panel or band, enter its area — the fill is dammed to that area and the flood coat still covers the whole top.
Most embedded bar tops pour the fill inside a dam or rail and only let the final flood coat run over the edges. If your fill layers run over too, their drips are added.
1 is normal. Add one after a fill pour for a single, even surface.
A thin first coat brushed or scraped into bare wood, so air in the grain doesn’t bubble up into the clear coat.
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 · ratio · SG A …
%
What stays in the bucket and on the spreader. Edge drips are counted separately.
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. Big batches heat up and thicken sooner, so pros mix the next one while the last is being poured.
$
Optional — your kit price, for a cost estimate
Tabletop epoxy to buy2.8 gal11.2 qt · 10.6 L
Kits to buy
3 kits
Fill depth used
3/8 in (yours)
Fill pour (buries the items), incl. waste
1.56 gal (6.24 qt · 5.91 L)
Fill layers at 1/8–1/4 in (3–6 mm) each
2–3
Flood coat(s) + film on the edges, incl. waste
1.12 gal (4.48 qt · 4.24 L)
Edge drips (runs off and is lost), incl. waste
14.9 fl oz (0.46 qt · 0.44 L)
Bar top area
13.3 sq ft
Batches to mix
3 batches
Per batch (volume, then weight)
A 1.86 qt (4.47 lb) + B 1.86 qt (3.69 lb)
When mixing — Part A (resin)
1.4 gal (5.59 qt · 5.29 L)
When mixing — Part B (hardener)
1.4 gal (5.59 qt · 5.29 L)
Part A by weight
13.4 lb (215 oz · 6.09 kg)
Part B by weight
11.1 lb (177 oz · 5.03 kg)
Left over from the last kit
0.2 gal (0.82 qt · 0.77 L)
  • What to buy: 3 × 1 gal tabletop epoxy kits. Each kit has both bottles (resin + hardener) — you don’t buy them separately. Looking at a different kit size? Change Kit size above.
  • A fill that deep is 2–3 layers of tabletop epoxy poured 1/4–1/8 in at a time, each inside the recoat window — or fewer with a product rated for thicker pours.
  • The fill is poured inside a dam or raised rail, so it doesn’t run over the edges — no drips are counted for it. Only the final flood coat runs over the coated edges.
  • Glue the caps down first and run a bead of glue or epoxy round each rim, so the air trapped underneath stays put instead of bubbling up through the fill.
  • Pouring onto bare wood? Choose a seal coat above — it stops air in the grain bubbling up into the clear coat.

For this job · affiliate link
Tabletop / bar top epoxy kitYour 3/8 in fill is 2–3 layers of ordinary tabletop epoxy; a bar-top product rated for thicker pours cuts that down. You need 2.8 gal, so 3 × 1 gal kits — or price one bigger kit, which is often cheaper per gallon.
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Kits for an 8 ft bottle cap bar top, by kit size

Kits for an 8 ft bottle cap bar top, by kit size
Kit sizeTabletop epoxy to buyKits to buyLeft over from the last kit
1 gal2.8 gal3 kits0.2 gal
1.5 gal2.8 gal2 kits0.2 gal
2 gal2.8 gal2 kits1.2 gal
3 gal2.8 gal1 kit0.2 gal

What to know about a bottle cap bar top

Crown caps are roughly 1¼ in across once you count the fluted skirt, so this 8 ft × 20 in top takes somewhere around 1,200 caps in straight rows, or about 1,400 nested — a lot of bottles, so start collecting early and sort by colour before you glue anything.

Which way up changes the resin. Glued open side down (logo up), each cap traps a pocket of air, so it takes up room like a solid disc: in straight rows the caps cover about 78.5% of the top and fill about 0.2 in of the 3/8 in depth, which is why the fill here is 1.56 gallons. Seal each rim with a bead of glue or epoxy so the air stays put instead of bubbling up through the fill. Laid open side up, each cap is a little cup that fills with resin, and the same fill takes about 3.27 gallons — pick “open side up” in the calculator to see the whole job, about 4.51 gallons.

Plan the layers and the batches. At 3/8 in the fill is 2–3 layers of tabletop epoxy; TotalBoat, for example, caps its TableTop at 1/4 in per coat. Each layer is well under a gallon, but mixed epoxy in a container heats up and cuts its own working time, so mix no more than about a gallon at a time and pour each batch straight away. Tack a seal layer first to lock the caps, then the fill layers, then the flood coat.

Watch the kit maths. Three 1-gallon kits leave only about 0.2 gallons (26 fl oz) spare on 2.8 gallons — enough for spills, but not for a seal coat to lock the caps down, which takes about a quarter of a gallon on open-grain wood. A fourth gallon, or two 2-gallon kits (1.2 gallons over), is safer. Your dam or rail must stand at least 1/2 in above the wood for the fill and flood coat together. A shallower penny bar top needs about 2.4 gallons; a plain 8 ft bar top about 1.24.

Different size? Use the full Bar Top Epoxy Calculator.

What you’ll need

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Frequently asked questions

How much epoxy for a bottle cap bar top with a 1/2 inch fill?

About 3.89 gallons on an 8 ft × 20 in bar — 2.65 gal of fill in 2–4 layers, plus the flood coat and drips.

How many 3-gallon kits for a bottle cap bar top?

1 kit of 3 gallons for the 2.8 gallons — only 0.2 gal to spare, so add a small kit if the wood needs a seal coat.

How much epoxy for a bottle cap bar top with two flood coats?

About 4.03 gallons: the same 3/8 in fill plus 2.24 gal for two 1/8 in flood coats and 29.8 fl oz of drips.

How much epoxy for a bottle cap bar top with the caps open side up?

About 4.51 gallons — the resin fills every cap, so the 3/8 in fill takes 3.27 gal instead of about 1.56 gallons with the caps open side down.

Other common sizes

Sources