Injection Moulding Cost Estimation: Part Weight, Runners & Regrind, Cavities, Cycle Time, Machine Rates, Tooling & Part Price

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.

• Turn six fictional parts' CAD volumes into part weights with a density lookup, build each tool's shot weight from cavities and runner, measure the runner share and check how much of the barrel's shot capacity each shot uses.
• Compare two parts side by side: gross material per good part with scrap, the regrind you may feed back under the customer's cap, the blended price of resin and colour masterbatch, and the material cost per 1,000 good parts.
• Compare five tool layouts for the clip housing by good parts per hour, parts per shift and production days for a 250,000-piece order, and find the smallest cavity count that still meets the delivery window.
• Build the cycle time of five parts from injection, holding, cooling (from a fictional wall-thickness table) and mould moves, see how much of the cycle is cooling, estimate cooling for a wall between table rows and turn a thinner wall into machine hours saved.
• Add up the projected area of six tools, turn it into the clamp force with a fictional pressure factor per resin plus a margin, pick the smallest machine class that covers it with XLOOKUP's next-larger match and fetch that machine's hourly rate.
• Build the hourly rate of a fictional 120 t machine from depreciation, maintenance, floor space, energy and a shared operator, add the overhead surcharge and turn the rate into the conversion cost per good part of the lid.
• Compare a 2-, 4- and 8-cavity tool for the clip housing by tool cost, conversion cost and total cost per part over the lifetime volume, and work out the volume from which the 4-cavity tool beats the 2-cavity one.
• Build Brackwater's quote for the clip housing at three order volumes: production runs, set-up and order cost per part, full cost, a price with the target margin rounded to a tenth of a cent, and a chart of the price breaks.