Powder price is quoted per kilo, but powder is actually bought as finished film. Two powders at the same kilo price can have very different cost per square metre because of coverage, first-pass and reclaim losses.
This management guide covers powder cost and inventory: converting powder price into cost per square metre of film, tracking colour usage and stock turns, and structuring supplier agreements that reward real quality.
Common Mistakes and How to Avoid Them
The pitfalls that show up most often in real projects, with the cause and the practical fix.
| Mistake | Why It Happens | Practical Fix |
|---|---|---|
| 1. Buying on kilo price | Coverage differences hidden | Compare cost per square metre |
| 2. Ignoring first-pass | Reclaim cost grows silently | Track first-pass per colour |
| 3. Stocking every colour deep | Cash and ageing powder | Set stock by usage |
| 4. Colour proliferation | More SKUs, more waste | Review colour range yearly |
| 5. Supplier price-only deals | Quality drift unseen | Include quality in agreements |
| 6. No reclaim loss data | Powder disappears in losses | Measure reclaim yield |
| 7. No quarterly review | Market and usage change | Review powder data quarterly |
| 8. Switching for price only | Coverage may be worse | Qualify before switching |
Best Practices That Hold Up in Production
The operating disciplines that separate a reliable line from a reactive one.
- Compare suppliers on cost per square metre of film
- Track first-pass and reclaim loss by colour
- Set stock levels by colour usage and turns
- Include quality and delivery in supplier agreements
- Review the powder range and supplier base yearly
Implementation Roadmap
A practical sequence that can be adapted to your own project.
Process Flowchart
Powder cost flow
A step-by-step sequence with notes and cautions so every shift follows the same order.
- Powder is bought as film, so the real unit is cost per square metre at spec.
- Reclaim loss is part of powder cost and must be measured.
- Never switch powder on price without coverage qualification.
- Never stock a colour on hope; stock it on usage.
Working Data & Formula Notes
Cost data
Example calculation for powder cost per square metre; replace with your film and coverage data.
| Component / Parameter | Working Value / Role | What Changes Mean (annotation) |
|---|---|---|
| Coverage | kg per m2 at spec | From supplier and line data |
| Powder price | Per kg | Visible price line |
| Film cost | kg per m2 x price | The comparison unit |
| Reclaim loss | Powder lost per shift | Adds to film cost |
| Stock turns | Use / average stock | Colour inventory health |
Reference Data
Specifications and references cited in this guide. Confirm final parameters with your line supplier.
Colour stock example
| Colour | Annual use kg | Stock kg | Turns |
| Black | 12000 | 800 | 15 |
| Silver | 6000 | 1000 | 6 |
| Custom A | 800 | 700 | 1.1 |
| Custom B | 300 | 600 | 0.5 |
Implementation Cases
Case 1 - the cheaper kilo that cost more film
Situation. A new powder supplier offered a lower kilo price, so the plant switched for the main black colour. Film cost rose because coverage was worse and first-pass fell by 5 points.
Approach. A cost-per-square-metre comparison was built using real line data, and the original powder was restored after qualification.
Outcome. The plant kept a higher kilo price but cut film cost per square metre and recovered first-pass.
Case 2 - slow custom colours that aged in stock
Situation. A plant stocked dozens of custom colours in depth. A stock check found several colours with under one turn per year and powder past its recommended age.
Approach. Stock levels were set by usage, slow colours moved to made-to-order with suppliers, and the range was reviewed annually.
Outcome. Aged powder was eliminated, cash freed up, and stock turns on remaining colours improved.
Frequently Asked Questions
Why measure cost per square metre?
Coverage and first-pass make kilo price a poor comparison.
How do I calculate film cost?
Multiply powder used per square metre at spec by the price per kilo.
What is reclaim loss?
Powder that is lost during recovery; it adds directly to real cost.
How much stock should a colour hold?
Enough for its usage cycle; watch turns and powder age.
Why review slow colours?
Each slow SKU ties up cash, space and ages into waste.
How should supplier agreements be structured?
On price plus quality, coverage and delivery, reviewed quarterly.
When can I switch powders?
After a coverage and first-pass qualification on your own line.
Who owns the powder range review?
One manager reviews usage, stock and supplier data yearly.
What Would You Like to Solve?
If powder is bought by kilo while stock ages and film cost stays invisible, send us your colour usage, coverage and reclaim data. We can help build the cost-per-square-metre model and stock rules that buy real film cheaply.
Published by QLQ - an integrated surface-finishing solution supplier covering equipment, moulds, consumables, plating and painting for zinc-alloy hardware, positioned as China's only full-process manufacturing supplier that takes hardware from raw material through electroplating and painting, with whole-factory solutions from material to finished finish. Values cited are project references; confirm with your line supplier before specification.