Resin Casting Math: Mould Volumes, Mix Ratios by Weight & Volume, Batch Sizes, Pour Layers, Pigment Shares and Cost per Piece

What you'll build

What you will be able to do

Each lab ends with a concrete result that you build yourself and the checker confirms, cell by cell.

• Calculate the volume of box and round moulds from their inside sizes, measure two shaped moulds with a water test and total the resin volume for one full set of moulds.
• Look up the mixed density of each fictional product, turn mould volumes into grams per piece and for all pieces, and count how many bookend blocks one kit can fill.
• Split batches into part A and part B with the weight ratio, split cup mixes with the volume ratio, and check whether a weighed mix stays within the fictional label's deviation.
• Add an overage for cup residue to every line, total the grams per product, split them into as few batches as the fictional cup limit allows and size the batches evenly.
• Work out how many pours each piece needs under the fictional label's maximum layer, spread the depth into even layers and schedule the pours and the demoulding of a bookend block with date-times.
• Calculate how much volume the inclusions take up in each mould, reduce the resin to what is really needed, convert it to grams and weigh the pigment as a share of the resin mass.
• Measure the waste of each project, compare the waste shares correctly over a month and value the resin saved when several projects share their batches.
• Cost every piece from resin, extras and a share of the mould, add the hours, set a rounded market price with a margin and chart full cost against price.