Precision Tool for Artisans
Mold Material Calculator
Stop guessing. Weigh your mold with water once, and get the exact powder, liquid, wax and cost for every piece you cast — with batch quantities, waste buffer and a per-unit price that actually holds up when you sell.
Material calculator
01 — Mold Measurement
Fill the empty mold with water, weigh it. 1 ml water = 1 g.
Solid volume only. For a hollow jar, subtract the inner cavity, or measure with water — always more accurate.
02 — Per Piece
≈ 0.00 oz
≈ 0.00 oz
Any field works — type in one, the other two follow.
03 — Batch & Buffer
Covers what stays in the cup, the spout and the stir stick. 5–10% is realistic for most studios.
04 — Cost & Pricing Know your number before you set a price
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A BN platinum silicone mold typically runs 200–500+ pours with proper care.
Wick, fragrance, pigment, sealer, box, label.
Guide figures only. Add your own shipping, platform fees and tax before you commit to a price list.
Recipe copied to clipboard.
Get the material for this batch
Which material should you pour?
The same mold, four completely different products. Pick by the result you're selling.
| Material | Factor g per 1 ml |
Mix ratio powder : liquid |
Liquid | Demold | Best for |
|---|---|---|---|---|---|
| Boowannite Aqua eco resin system |
1.6 | 1 : 0.35 | Boowannite liquid | ~40–60 min | Terrazzo, pastel colour work, lightweight decor, fast studio turnaround |
| Normal Gypsum Plaster of Paris type |
1.6 | 1 : 0.28 | Pure water | ~30–45 min | Prototyping a new mold, test pours, low-cost practice pieces |
| OmniCast™ Cement UHPC casting system |
2.3 | 1 : 0.15 | Pure water | Cures 2 h, demold 4 h | 120 MPa+ strength, crisp fine detail, outdoor & wet-room pieces, production runs |
| Wax Single component |
0.8 | — | None | Varies by wax & mass | Pillar, taper, 3D sculptural and refill candles |
Factors are density-based and hold across mold sizes. Demold times are guidance at ~25°C / 77°F — cold studios run slower.
How to measure your mold's water weight
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01
Zero the scale
Put the empty, dry mold on a digital scale and tare it to zero. Use a 0.1 g scale if you can — for small molds it matters.
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02
Fill with water
Fill the cavity to the exact line you'd pour to. For candle jars, that's the finished fill line, not the very rim.
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03
Read the number
Whatever the scale says in grams is your mold water weight in ml. 168 g of water = 168 ml capacity.
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04
Write it on the mold
Note it on the support shell or in your product sheet. Measure once, reuse it for every batch forever.
Dry the mold fully before casting. Trapped water changes the surface finish on cement and gypsum.
Questions makers actually ask
Why does the calculator ask for water weight instead of the mold's dimensions?
Because it's the only measurement that's exact. Molds have curves, undercuts, textured walls and support shells — geometry formulas always drift a few percent, and on a 40-cavity batch that drift becomes a wasted bag of powder. Water fills the real cavity. One measurement, permanently accurate.
How much wax do I need for my candle mold?
Multiply the mold's water weight in ml by 0.8. A 200 ml mold takes roughly 160 g of wax. Wax is less dense than water, which is why the number is lower than the volume. Different waxes vary slightly — soy, coconut blends and paraffin all sit near 0.8, so use it as your working figure and adjust once you've poured your first piece.
Why is the OmniCast™ factor 2.3 when Boowannite is 1.6?
Density. OmniCast™ is an ultra-high-performance cement that packs far more mass into the same volume — which is exactly where its 120 MPa+ strength comes from. The same mold will produce a noticeably heavier, more substantial piece in OmniCast™ than in Boowannite. That weight is often what makes a product feel premium in the customer's hand.
Do I add the buffer to the powder or the liquid?
Both, proportionally — which is what this calculator does. Scaling only one side changes your mix ratio and that's how you get soft, chalky or cracked pieces. The buffer covers residue left in the mixing cup, on the spatula and in the pouring spout.
Can I use these ratios for Jesmonite?
Use the Boowannite setting as your starting point — it's an aqua eco resin system built for the same kind of work. Always check the ratio printed on your own supplier's packaging, since acrylic-liquid systems differ between brands, and run one test pour before committing to a production batch.
My mold has several cavities. What do I enter?
Enter the water weight of a single cavity, then set "Pieces / cavities" to the number you're filling. Doing it that way keeps your per-piece cost honest, which is what you need when you price the product.
Is the pricing suggestion realistic?
The ×2 wholesale / ×4 retail structure is the standard handmade-goods keystone model, and it's a floor rather than a target. It has to absorb your shipping, marketplace fees, returns and the pieces that don't survive demolding. If your calculated retail feels low next to comparable products, the market is telling you something — sculptural cast pieces usually sell on design and finish, not on material cost.
Turn the numbers into a product line
Makeit™ pairs every mold with a curated list of exactly what you need to finish it — no guesswork, no half-used supplies.
