Every plant manager we work with wants the same thing: a single page they can put in front of the CFO that shows when the new clamp system pays for itself. So we built one and we are giving it away — no email gate, no download nag.
Run the interactive calculator below. If you want the editable spreadsheet version, the link is in the call-to-action at the bottom of this page.
Interactive ROI calculator
QMC ROI Calculator — enter your numbers
Results
Numbers update as you type. Use bad-day average for change time, not best case. Include mold-side hardware in the investment figure or your payback will look better than it actually is.
What the calculator does
It compares your current mold change process with a quick mold change (QMC) setup over a 36-month horizon. You enter eight numbers from your shop floor. The model returns annual hours lost (before and after), annual cost of that lost time in your currency, payback period in months, three-year cumulative savings, and an NPV at your discount rate.
That is enough for most capex approvals at most plants in Southeast Asia, India, Mexico and Turkey.
Get the editable spreadsheet
Prefer to work in Excel, WPS or Google Sheets? Download the same model as a CSV that opens in any spreadsheet tool — formulas auto-recalculate. Request the editable ROI template here. No form, no email gate; the file is yours.
Inputs — what to gather before you start
Before opening the calculator, walk to the shop floor with this list.
- Press tonnage class — useful for context only.
- Number of mold changes per shift (or per day).
- Working days per year — most Asia plants run 280–320.
- Current mold change time — total minutes from “press stop” to “first good part”.
- Expected mold change time after QMC — be conservative; if a vendor promises 5 minutes, plan for 10.
- Downtime cost per hour — fully loaded cost, including operators, the empty press, the missed shipments. Most plants underestimate this by 30–50%.
- QMC system investment — hardware + mold-side hardware + commissioning + training. The press-side clamps are usually less than half the total. Ask your supplier for the full bill of materials.
- Discount rate — if your finance team does not give you one, use 10% for Southeast Asia, 7% for Europe, 12% for Bangladesh or Pakistan.
A worked example
To show what good numbers look like, take a real case from a Vietnamese auto-parts molder we worked with last year (anonymized, numbers rounded). Four mold changes per day, 290 working days, current change time 110 minutes, target 12 minutes, downtime cost USD 80 per hour, full QMC project USD 42,000.
The model returns annual downtime hours of 2,127 before and 232 after, annual savings of USD 151,600, payback in 3.3 months, and three-year cumulative net savings of USD 412,800. The CFO signed off the same week.
Common mistakes when running these numbers
The numbers are only as honest as the inputs.
The first mistake is using stopwatch time from a good day, not average time. Walk the floor on a bad day. Use the bad-day average.
The second is forgetting the mold-side hardware. A pair of hydraulic clamps for one press might cost USD 3,000, but the flanges, T-blocks and back plates for the molds that go on that press can easily be USD 7,000 more. Build that into the investment figure or your payback graph will lie.
The third is treating cost-per-hour as just lost revenue. The real cost includes idle operators, idle utilities, the production planning chaos when an order ships late, and the customer credibility damage when you miss a delivery date twice in a row. For tier-1 automotive customers, that last item is the largest line.
When the ROI does not work
Sometimes the answer is no. Run the numbers honestly and you will see it.
If you only change molds once or twice a day and your downtime cost is below USD 30 per hour, a full QMC system rarely pays back in under 24 months. In those cases, look at simpler upgrades first — a few manual hydraulic clamps and a SMED training program might give you 70% of the gain at 20% of the cost.
A vendor who insists the ROI works in your situation when the math says otherwise is selling you a system, not solving your problem.
How to use the result internally
Print the result and bring it to the next operations meeting. Two slides usually win the argument: a comparison of current downtime hours per year (in red) versus after-QMC hours (in green), and a cumulative cash position month by month with the breakeven point marked.
Most CFOs do not need more. If yours does, attach the editable spreadsheet so they can stress-test the assumptions themselves.
Frequently asked questions
Does this calculator include the cost of training?
Yes, training and commissioning are included in the investment line. Leave them out at your peril — without proper SMED training, the new clamps do not get you the change-time you paid for.
What discount rate should I use?
10% is a safe default for Southeast Asia and Latin America. Use 7–8% for Europe, 12% for Bangladesh or Pakistan. Your finance team almost always has an internal hurdle rate; use that if you can get it.
My plant runs three shifts. Does the calculator handle that?
It handles it through the “mold changes per day” field. If you change four times per shift across three shifts, enter 12.
Can I use this for stamping press die change too?
Yes, the math is identical. Replace “mold” with “die” and “QMC” with “QDC” mentally. Stamping plants usually see slightly faster payback because die changes are more frequent.
What if my downtime cost varies by product?
Use a weighted average — sum (hours per product × hourly cost per product) divided by total hours. Plants that make this distinction usually find their real number is 20% higher than the simple average.
Final thought
The hardest part of justifying a quick mold change project is not the math. It is making the math match the reality of your shop floor. Walk the floor first, then sit down with this calculator. If you want a sanity check on your numbers, send them to our application team — we will tell you honestly whether the project pays back or whether you should hold off.
Related reading: Hydraulic vs Magnetic Quick Mold Change System — which one fits your factory.
Want a second pair of eyes on your numbers?
Email your inputs — press list, mold mix, current change time — and our application engineers will run them with you, free of charge. Contact KINGHOU →
