ClayFit: Clay Shrinkage

Every clay body shrinks. Yours does not shrink by the number on the bag — it shrinks by whatever your clay, your kiln and your firing schedule actually do. ClayFit measures that, remembers it, and works backwards from the size you want. YOUR CLAY, NOT THE CATALOGUE Manufacturer figures are a starting point. The rate you get depends on the batch, the bisque, the cone you fire to and the atmosphere in the kiln. ClayFit stores a measured shrinkage rate for each clay and each firing profile, built from test bars and finished pieces you measured yourself. WORK BACKWARDS FROM THE FINISHED SIZE You know the mug should be 90 mm across when it comes out of the glaze firing. ClayFit tells you how wide to throw it wet. Enter a target and it gives you the wet dimension, using your own measured rate — and it shows you the rate it used, how many measurements it came from, and how much those measurements varied. EVERY STAGE, NOT JUST THE TOTAL Record a test bar wet, then bone dry, then after bisque, then after the final firing. ClayFit works out the shrinkage at each step and the total from wet to fired. Enter the wet measurement today and come back weeks later to add the rest — the record waits for you. VOLUME TOO A 500 ml bowl fired is not a 500 ml bowl wet. Linear shrinkage compounds in three directions, so ClayFit does the cube for you and tells you the wet equivalent volume to aim for. WHAT YOU GET • Unlimited firing profiles and measurements per clay • Average shrinkage with sample count and spread, so you know how solid it is • Reverse calculator for diameter, width, height, length and volume • Round up to your preferred step, because short is worse than long • Outlier detection — impossible readings are flagged and left out • Home Screen widget showing your active clay and its rate • mm, cm or inches; ml, litres or fluid ounces; Celsius or Fahrenheit • Everything stays on your device. No account, no network, no tracking The Unlimited upgrade is a one-time purchase, not a subscription. It removes the clay-body limit and adds CSV export. ClayFit gives estimates based on the measurements you enter. Real pieces vary with wall thickness, throwing, drying and where they sit in the kiln. Test bars are still the honest way to check a new batch.