How do you calculate potting compound cost per assembly?

Work out the compound each assembly takes (fill volume x density, plus mixing waste) and price it per kg, then add the job's dispense labour, setup, cure and overhead divided by the assemblies. 650 assemblies at 2.20 of compound each is 1,430; with 380 of labour and setup and 260 of overhead, 2,070, or 3.18 each, the Potting Compound Cost calculator's own example.

How do I find the fill volume?

The cavity volume less the volume of the components, from CAD, or weigh an assembly before and after potting and divide by the density. Enter it per assembly in cm³.

What is mixing waste?

Compound lost to purging, static mixer tips and material that passes its pot life, as a share of what is dispensed. It is set per compound on Setup; meter-mix-dispense equipment and hand pours usually differ.

Why do small runs cost so much more?

Dispense labour, setup, the cure oven and fixtures are largely job costs, spread over the assemblies. 440 over 80 battery modules is 5.50 each; the same costs over 1,300 assemblies would be a few cents.

Does it include degassing, rework and scrap?

Only if you include them in the labour and setup or cure and overhead columns. Shelf life and minimum order quantities of the compound are not modelled.

Does the workbook use macros?

No. It is a plain .xlsx with ordinary formulas, tables and native charts. The Verify sheet re-checks the formulas against fixed test jobs and shows Self-check: PASS.

Industry Cost Kits

Potting Compound Cost Excel Template

Potting cost per assembly = fill volume × density × (1 + mixing waste) × price per kg + (dispense labour and setup + cure and overhead) ÷ assemblies. Give every potting job a row and see its compound use, its cost per assembly, where the potting price goes, and its margin against your target.

Free, and a plain .xlsx with no macros to enable. A CSV with live formulas and a printed how-to guide come with it.

Overview

This potting compound cost template is a working Excel workbook for process and cost engineers, estimators and production managers potting and encapsulating electronic assemblies. Each potting job is one row with its compound, the assemblies in the run, the fill volume each takes, the dispense labour and setup, the cure oven, fixtures and overhead, and the quoted potting price per assembly. The compound list on Setup gives the mixed density, price per kg and mixing waste, so the workbook works out the grams and the compound cost of each assembly rather than asking you to estimate it. It ships with ten jobs in three compounds at a fictional electronics maker, so every tile and chart is filled in when you open it.

In the example a sensor housing takes 102 cm³ of urethane at 1.45 g/cm³, 157 g with 6% mixing waste, 2.20 of compound at 14.00 a kg. 650 housings with 380 of dispense labour and setup and 260 of cure and overhead cost 2,070, or 3.18 each, a 26% margin at 4.30; the repeat run of 1,300 spreads the same kind of costs to 2.77 each and makes 35.5%. A first run of 80 battery modules takes almost a kilogram of compound each and carries 5.50 of labour and overhead per module, making 7% at 21.00.

Rework and scrapped assemblies are only in the cost if you include them. The download is a plain .xlsx with no macros. A CSV with live formulas is also included for other tools; the dashboard, charts, dropdowns and self-check are in the .xlsx.

What this template includes

Setup sheet with your company, currency, target margin and near band, and the potting compounds with their density, price per kg and mixing waste
Jobs table, one row per potting job: assembly, compound, assemblies, fill volume per assembly, dispense labour and setup, cure and overhead, and quoted price per assembly, with a Check column
Per job: compound per assembly in grams, compound cost per assembly, compound used in kg, compound cost, total cost, cost per assembly, margin and a status in words
Dashboard with four tiles (jobs, potting cost, compound used, jobs below target margin), cost per assembly as a share of price split into compound, labour and overhead, margin above or below target, and the job table
Method sheet with every formula, and a Verify sheet that re-checks the formulas against an independent reference and the Potting Compound Cost calculator (Self-check: PASS)
CSV with live formulas for the Jobs table; the dashboard, charts, dropdowns and self-check are in the .xlsx

Suggested use case

Use it to price potting and encapsulation as a value-added operation, to compare compounds on cost per assembly, or to see how much a small run's setup and cure overhead adds to each part.

How to use it

On Setup, type your company, currency and target margin, and list your compounds with their density, price per kg and mixing waste.
On Jobs, give each potting job a row: compound, assemblies, fill volume per assembly, dispense labour and setup, cure and overhead, and the quoted price per assembly.
Fix anything the Check column names.
Open the Dashboard: where each assembly's potting price goes and its margin against your target.

Frequently Asked Questions

How do you calculate potting compound cost per assembly?: Work out the compound each assembly takes (fill volume x density, plus mixing waste) and price it per kg, then add the job's dispense labour, setup, cure and overhead divided by the assemblies. 650 assemblies at 2.20 of compound each is 1,430; with 380 of labour and setup and 260 of overhead, 2,070, or 3.18 each, the Potting Compound Cost calculator's own example.
How do I find the fill volume?: The cavity volume less the volume of the components, from CAD, or weigh an assembly before and after potting and divide by the density. Enter it per assembly in cm³.
What is mixing waste?: Compound lost to purging, static mixer tips and material that passes its pot life, as a share of what is dispensed. It is set per compound on Setup; meter-mix-dispense equipment and hand pours usually differ.
Why do small runs cost so much more?: Dispense labour, setup, the cure oven and fixtures are largely job costs, spread over the assemblies. 440 over 80 battery modules is 5.50 each; the same costs over 1,300 assemblies would be a few cents.
Does it include degassing, rework and scrap?: Only if you include them in the labour and setup or cure and overhead columns. Shelf life and minimum order quantities of the compound are not modelled.
Does the workbook use macros?: No. It is a plain .xlsx with ordinary formulas, tables and native charts. The Verify sheet re-checks the formulas against fixed test jobs and shows Self-check: PASS.