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Resin calculator
Estimate casting volume and split your A:B mix with the ratio printed by the manufacturer.
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- Calculated on your device
02 / Your results
| Component | Volume |
|---|---|
| Part A | 73.33 ml |
| Part B | 36.67 ml |
Your mould holds 100 ml before the extra allowance. Measure components by volume to match the selected product ratio.
This geometric estimate assumes component volumes add together. It does not account for inserts or irregular shapes. Follow your product’s maximum pour depth and mixing instructions.
How the calculation works
The mould's volume is increased by your waste allowance, then divided by the A:B ratio. Weight ratios need the actual density of both components to convert grams and millilitres correctly.
Try an example
A 10 × 10 × 1 cm rectangular cast holds 100 ml before waste. With 10% waste, prepare 110 ml total.
How to use this calculator
- Choose a rectangular or circular mould and enter its inside dimensions and pour depth in centimetres or inches.
- Set an extra material allowance and enter your product's Part A : Part B ratio. Match the label's volume or weight basis; weight mode also needs each unmixed component's density in g/ml.
- Select Calculate resin. Measure A and B using the selected basis and follow your product's mixing and maximum pour-depth instructions.
Common questions
Are a 2:1 volume ratio and a 2:1 weight ratio interchangeable?
No. Components can have different densities. Select the ratio basis printed on your product and measure using that basis. The example's 2:1 ratio is illustrative and may not match your resin.
Why does weight mode ask for two densities?
Mould dimensions give a volume, while a weight ratio specifies masses. The calculator needs each unmixed component's density from the manufacturer's technical data sheet to connect them. It does not assume that 1 ml weighs 1 g.
Does the estimate include objects inside the mould?
No. It models an empty rectangular prism or cylinder, plus your extra allowance, and assumes component volumes add together. Inserts, irregular shapes and curing effects are not included.
Further reading: TotalBoat: epoxy ratios by weight and volume