WonksAnonymous
For manufacturing owners, operations leads and finance teams
Do the math before you buy the machine.
We write about what production really costs: payback on new equipment, cost per good pack, bottlenecks, downtime and imported machinery. Each piece shows its arithmetic with labeled example numbers, so you can swap in your own and see whether the answer changes.
Topics
Production Economics
What a good pack costs to make once downtime, scrap, changeovers and the slowest machine on the line are counted.
Automation Investment
How to tell whether a machine will pay for itself, starting from the full installed cost and the hours it will actually run, and how to check the answer once it is in.
Trade and Supply Chains
Everything between a supplier's price and a running line: freight, duties, installation, spares, fair quote comparisons, and when a contract packer beats owning the line.
Start here
Deciding whether to buy a machine
Start with what payback, ROI and TCO each tell you, then check whether your orders will keep the machine busy.
Chasing more output from a line
Find the bottleneck before you pay for speed, then put a number on each stop and changeover.
Comparing quotes from suppliers
Get every quote onto the same scope and trade terms before you compare prices.
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Average Fixed Cost Formula, Cost Per Unit Calculator, and Operating Leverage
Use the average fixed cost formula (AFC = TFC / Q) and unit cost calculator to see why an automated line costs more per pack than a semi-automatic line at 45% utilization.
Overall Equipment Effectiveness Formula, Calculator, and the OEE Financial Bridge
Use the overall equipment effectiveness formula (OEE = Availability × Performance × Quality) and financial calculator to test whether a +5% OEE gain saves cash or merely creates idle time.
ROI Calculation in Excel: Simple ROI, Discounted Payback, NPV, XNPV, IRR, and MIRR for Equipment CapEx
Compare simple ROI calculation in Excel against NPV, XNPV, IRR, XIRR, and MIRR formulas when equipment CapEx has milestone deposits, Q1 ramp-up scrap, and a Year 5 overhaul.
Cost of Goods Manufactured Formula: A Packaging WIP Reconciliation
Build a manufacturing-cost statement from raw-material usage, labor, overhead and WIP, then reconcile COGM to costed finished-goods receipts.
Variable Cost Formula: Packaging Line Examples Across Shift Limits
Model packaging materials, piecework, overtime and energy separately, with assumed examples showing where one variable rate stops working.
Manufacturing Capacity Utilization: Why the National Rate Is Not a Plant Target
Compare national capacity utilization, plant output, machine hours and OEE by their denominators, with a labeled plant example and a records checklist.
Allocate Manufacturing Overhead After Automation: Labor or Machine Hours?
Apply one manufacturing overhead pool on labor hours and again on machine hours. Rates and dollars stay blank until your records fill them.
Map the Peak Cash Gap on a Manufacturing Order
Separate net working capital and an operating working-capital figure from the monthly cash gap of one manufacturing order. Plant amounts stay blank.
Make or Buy at a Bottleneck: Calculate the Opportunity Cost
Compare avoidable make cost with purchase-and-delivery cost, then add only the contribution of orders the same hours could ship.
Build a Multi-Year Equipment Cash-Flow Model in Excel
A five-year Excel sheet for equipment cash that changes by year, with a negative overhaul year, cumulative recovery, and NPV.
Fixed, Variable and Total Cost: Formulas That Reconcile
Calculate FC, VC, TC, AFC and AVC with a worked production-line example, separate total and unit-cost charts, and copyable Excel formulas.
Calculating OEE on Packaging Lines: Availability, Performance, and Quality
A practical guide to calculating Overall Equipment Effectiveness (OEE) on packaging lines, diagnosing the six big losses, and avoiding bottleneck averaging errors.
Measuring the Cost of Unplanned Production Downtime
Three ways to value an hour of unplanned downtime (lost revenue, lost contribution, recovery cost), when each applies, and a worked 90-minute stop.
Contract Packing Versus Owning a Packaging Line
When a contract packer costs less than your own line, when it does not, and the non-price factors that decide the close cases, with a worked break-even.