Calculate resin for sphere molds and ball-shaped castings by diameter, waste buffer, and material cost.
Resin Mold Calculator
This resin mold calculator is for mold-based projects where the inside cavity controls the amount. It gives users a practical starting point before they move to cube, sphere, cylinder, coaster, or jewelry-specific pages.
Enter your measurements
Example inputs
Default dimensions, allowances and prices are example inputs. Replace them with your measurements and product label. Leave unknown product limits blank.
Mold resin estimate
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Start with the inputs to generate an order-ready estimate.
- Raw volume
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- Conservative
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- Projected cost
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- Part A / Part B
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- Layer guidance
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- Kits to buy
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- Standard
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- Product fit
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Why This Estimate Changed
What moved the number
- Enter the form values to see raw volume, buffer, and recommendation.
Next Step
Match the result to the right resin class
Use the estimate to narrow the resin class first. Then confirm product limits, cure behavior, and measurement assumptions before you make a buying decision.
Measurement diagram
Choose geometry or an actual known mold capacity
A simple 12 × 8 × 1 cm rectangular cavity holds 96 mL before waste. A mold with curved corners or inserts may hold less. If the supplier gives a mixed volume, use known capacity mode; if you measure it, follow a method compatible with the mold and resin. Six 50 mL cavities are 300 mL raw and 324 mL at 8% waste. Kit yield is the combined mixed volume, not the bottle size of Part A alone.
Product data before mixing
Use the exact product documentation for mixing basis, maximum layer depth, mixed batch volume and cure or recoat conditions. A dimensional estimate and a purchase allowance do not supply those material limits.
What this calculator covers
- Use inside dimensions or a known mixed volume per cavity.
- Count identical molds or sets and add a stated loss allowance.
- Small batches show mL; product limits and complete kit yield stay separate.
How to measure or set the inputs
- Choose inside geometry for a regular shape, or use a known cavity capacity where that mode is available.
- Set the number of identical pieces; the main quantity is the total batch, with a separate loss allowance.
- Check the raw quantity against a hand calculation or a product's published mixed capacity.
- Enter product ratio, limits and total kit mixed yield only when confirmed; purchase quantity is not a batch-mixing instruction.
Common mistakes that cost money
- Using outside mold dimensions.
- Ignoring embedded objects that displace resin.
- Using one large-cast estimate for many tiny molds without extra cup-loss buffer.
Project checklist before you buy
- Confirm the mold or surface is sealed before mixing resin.
- Measure depth twice at the deepest point of the project.
- Add extra material for waste, seepage, and edge soak-in.
- Confirm the resin type matches the intended pour depth.
- Prepare cups, stir sticks, gloves, and a level work surface.
FAQ
Questions people ask before buying epoxy
How do I account for inserts or hollow parts?
Dimension mode estimates a full regular shape. Use a known net cavity capacity or a separately measured displacement when inserts or hollow parts change that volume.
Should I fill any mold with water to measure capacity?
No universal measuring liquid is suitable for every material. Use a supplier's mixed capacity or a method compatible with the mold, substrate and resin, including its cleaning and drying requirements.
Does the result include the number of molds?
Yes. Enter capacity for one cavity or one complete set, then count identical units. The result already includes that count and the selected loss allowance.
Related Pages
Related calculators and guides
Calculate resin for cylinder molds, round columns, tumbler inserts, and cylindrical casts by diameter, height, waste, and cost.
Calculate resin for cube molds, block castings, dice blanks, and square resin forms by side length, waste, and cost.
Calculate resin for round coaster molds by diameter, depth, waste buffer, batch planning, and cost.
Estimate resin for dice molds and cube-shaped resin casts by side length, waste buffer, and project cost.
Estimate resin for jewelry molds, pendants, bezels, charms, and small cavity pours with realistic waste guidance.
Reviewed · Calculation notes and corrections