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How Much Coating Do You Need? Coverage & Consumption by Thickness

MGCoat ·

One of the first questions before an order is simple: how far does one litre go? Coverage depends almost entirely on the film thickness you apply. Here is the clear rule, a thickness-by-thickness table, and how to turn your board size into litres.

The simple rule: 1000 ÷ thickness

Spread one litre evenly over a surface and the area it covers (in m²) equals 1000 divided by the film thickness in microns. At 100 µm that is 10 m² per litre in theory; at 200 µm, 5 m²; at 500 µm, 2 m². In real production a little material is lost to overspray, edges and the brush or dip bath, so plan on roughly 70–85% of the theoretical figure.

Coverage per litre, by thickness

Theoretical and realistic coverage for one litre. 100 µm (0.1 mm): ~10 m² theoretical, ~7–8.5 m² in practice. 150 µm: ~6.6 / ~4.6–5.6 m². 200 µm (0.2 mm): ~5 / ~3.5–4.2 m². 250 µm: ~4 / ~2.8–3.4 m². 300 µm (0.3 mm): ~3.3 / ~2.3–2.8 m². 500 µm (0.5 mm): ~2 / ~1.4–1.7 m². 750 µm: ~1.3 / ~0.9–1.1 m². 1000 µm (1 mm): ~1 / ~0.7–0.85 m².

Which thickness should you choose?

For most electronics a 100 µm film is enough: even this thin layer is fully waterproof, and the cured coating is light enough that protected boards stay buoyant and float on water. Go thicker only for harsh mechanical exposure — boards that sit in hail, grit or mud for long periods may justify building up toward a 1 mm armour layer. Thicker means more protection but fewer m² per litre, exactly as the table shows.

Turn your board size into litres

Work out the area you want to coat, then divide by the coverage for your chosen thickness. Example: 100 boards of 12 × 8 cm is 100 × 0.0096 = 0.96 m² per side; at the standard 100 µm (≈7–8.5 m²/L) that is only about 0.11–0.14 litres. Coating both sides? Count roughly double. You don't have to do the maths yourself — the assistant on this site (the chat button) asks for your board size and quantity and returns the litres instantly — counting both faces of the board and defaulting to 100 µm unless you specify another thickness.

Boards per litre at 100 µm (common sizes)

A quick reference at the standard 100 µm layer, coating one side, using the realistic ~7–8.5 m² per litre. 5 × 5 cm: ~2,800–3,400 boards per litre. 10 × 10 cm: ~700–850. 10 × 15 cm: ~470–570. 15 × 20 cm: ~230–280. 20 × 30 cm: ~120–140. Coating both sides roughly halves these counts; a thicker film lowers them in the same proportion as the table above. Tip: in the site's chat you can just type a size like "10 × 15 cm" (or tap a sample) and add the quantity.

Approximate price

Pricing is provided through an official quotation. Tax and cargo to the destination country are added separately, so the final invoice varies from place to place — the figure here is the material only. For an exact, all-in quote for your country and volume, send your board size on WhatsApp and we'll confirm the litres and the total.

Liquid PCB Plastic Coating by MGCoat is a heat-free, plastic-based nano coating; at just 100 µm it already waterproofs boards, sensors and circuits, and you scale the thickness up only where the mechanical environment demands it.

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