The Plaster Calculator allows you enter the dimensions of a solid shape, and then calculates the volume of that shape as well as the approximate amount of plaster and water required using common plaster mixing formulas.
Download the USG Excel calculator.
The USG calculator contains some pretty esoteric formulas:
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First, calculate a ratio based on the consistency: ratio = (-0.00004 × consistency^3) + (0.0154 × consistency^2) - (2.23 × consistency) + 164.25
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Second, calculate pounds of plaster and water from ratio and consistency: ratio × cubic feet = pounds of plaster pounds of plaster * consistency / 100 = pounds of water
volume in cubic inches × 11 = grams of water
grams of water × (100 / consistency) = grams of Pottery Plaster
Keith Simpson, Alfred University
Water should be room temperature
Sift plaster through fingers into water
Slake plaster for 3 minutes
Mix for 3 minutes
volume in cubic inches / 80 = quarts of water
quarts of water × 3 = pounds of plaster
Simplified technique by Andrew Martin from "The Essential Guide to Mold Making & Slip Casting". This technique creates a slightly thicker plaster as Andrew has rounded the required water down to make the calculation simpler and allow for the water to be measured by volume.
npm install
npm run serve
npm run build
npm run test
npm run lint