Stick-Pack Changeover Costs: How Batch Size Sets the Per-Unit Price
By the Silk Foods Ceylon Editorial Team
Buyer’s snapshot
- On a short stick-pack run, the changeover often costs more line time than the filling. In the worked example below, one 90-minute changeover is 64% of the block for a 10,000-stick run and 15% for a 100,000-stick run.
- Not every change costs the same. A new print on the same film is quick; a new stick width means new forming parts and is the slowest change on the line.
- Sri Lanka’s manufacturing PMI read 53.0 in September 2026, with food and beverages named as a driver of new orders (Central Bank of Sri Lanka, October 2026). Shared line time ahead of the year-end season is not idle time.
- The batch-size table and the sequencing rules are the two parts to take into a quote conversation.
A brand owner comparing two stick-pack quotes usually compares the rate per thousand packs. That number hides the cost that moves most on a short run: the minutes when the machine is stopped, emptied, cleaned, re-threaded and checked before the next flavour starts. On a long run those minutes disappear into the average. On a short run they are the average.
This post works through that arithmetic for a drink-powder or seasoning brand booking time on a shared sealing line at the Silk Foods Ceylon (SFC) facility in Matale. It is a companion to the stick-pack capability one-pager, which covers fill tolerance, laminate and labelling. Here the question is narrower: how batch size and the type of change set the real cost of each stick.
What is a changeover on a stick-pack line, and why does it cost so much?
A changeover is every minute between the last good stick of one run and the first approved stick of the next. On a multi-lane stick-pack line that covers emptying the powder hopper and dosing auger, cleaning product-contact parts, swapping the film reel, re-registering the print, resetting fill weight and passing a first-article check. The line produces nothing saleable during that time.
The cost is fixed per change, not per stick. Operators, power, floor space and quality staff are paid for the stopped hour exactly as for a running hour. The first sticks after restart are also usually scrapped while seal temperature, cut position and fill weight settle, so a changeover consumes some laminate and powder as well as time.
Two rules from outside the factory make the stop longer than a mechanical swap. The BRCGS Food Safety Standard asks for a documented check at each product change that the previous run’s printed packaging and labels have been cleared from the line (clause 6.2.2, as summarised by ASC Food Safety, 2026). And the net-weight rules most packers work to require the batch average to reach the labelled weight, so dosing must be proven on the new SKU before the run is released, as covered in the stick-pack one-pager’s fill-weight section.
How does batch size change the per-unit cost of a short run?
Batch size decides how many sticks share the fixed cost of the changeover. With a changeover fixed at 90 minutes, the stopped time is 64% of the block for 10,000 sticks and 15% for 100,000. Fill cost per stick barely changes with run length; changeover cost per stick falls in direct proportion to it.
The table below is a worked example with round numbers, built so the arithmetic is easy to follow. It assumes a staffed line hour costs LKR 12,000, the line produces 12,000 good sticks an hour once running, and one changeover takes 90 minutes. These are illustrative figures for the maths, not SFC’s line rates, which are quoted per SKU at brief.
| Run length (sticks) | Filling time | Changeover share of the block | Changeover cost per stick | Total line cost per stick |
|---|---|---|---|---|
| 5,000 | 25 minutes | 78% | LKR 3.60 | LKR 4.60 |
| 10,000 | 50 minutes | 64% | LKR 1.80 | LKR 2.80 |
| 25,000 | 2 hours 5 minutes | 42% | LKR 0.72 | LKR 1.72 |
| 50,000 | 4 hours 10 minutes | 26% | LKR 0.36 | LKR 1.36 |
| 100,000 | 8 hours 20 minutes | 15% | LKR 0.18 | LKR 1.18 |
Read the last column, not the third. Going from 5,000 to 25,000 sticks cuts line cost per stick by more than 60%. Going from 25,000 to 100,000 cuts it by about another third. The curve flattens fast: past a certain run length, a longer run saves little, and the extra stock ties up cash and shelf life instead.
The point where the curve flattens depends on the changeover, not the filling speed. Halve the changeover to 45 minutes and the 10,000-stick run falls from LKR 2.80 to LKR 1.90 per stick on the same assumptions. A faster filler, holding the 90-minute changeover, barely moves that small run at all, because the stopped time dominates.
From the SFC team
On short runs, the fastest way to lower a co-packing quote is usually to remove a changeover rather than to ask for a lower rate. A brief that arrives with fewer variants, one film width and every input on site gives the planning team more room to price than a discount request does.
Which changes cost the most line time?
Changes fall into four rough tiers. A print change on the same film is the shortest. A fill-weight change adds a dosing reset and a fresh weight check. A flavour change adds emptying and cleaning, longer still if the next powder is milder or allergen-free. A width or length change, which needs new forming parts, is usually the slowest.
The table ranks the common changes by what has to happen while the machine is stopped. Minutes are not given because they depend on the machine, the powder and the cleaning validation; SFC confirms them per SKU at brief.
| Type of change | What happens while the line is stopped | Relative cost |
|---|---|---|
| New print, same film width and same powder | Reel swap, print registration, label-clearance check | Lowest |
| New fill weight, same film and powder | Dosing reset, first-article weight check, code change | Low |
| New flavour, similar powder, dry clean | Hopper and auger emptied, dry clean, line clearance, new reel | Medium |
| Strong to mild flavour, colour, or allergen-free after allergen | Full clean of product-contact parts, drying before restart | High |
| New stick width or length | Forming tubes, slitter and cutter changed and reset | Highest |
Two practical consequences follow. First, a range that shares one stick width avoids the most expensive change entirely. Second, the cleaning tier depends on the order in which flavours run, which the brand can influence before the block is booked.
How should a multi-flavour range be sequenced?
Run the range from mild to strong, light to dark, and allergen-free before allergen-containing, all within one stick width. That order lets most changes use the shorter dry clean, because a trace of the previous powder does not affect the next one. Reverse the order and every change needs a full clean.
Take a hypothetical drink brand with four 5 g flavours: lemongrass, ginger, cocoa and a milk-containing cocoa blend. Sequenced lemongrass, ginger, cocoa, then milk cocoa, the first three changes can be dry cleans and the full wet clean falls once, at the end of the block, when the line is cleaned anyway. Sequenced the other way, milk cocoa first, the line needs a full allergen clean before anything else can run.
The same logic applies to label risk. Under the Food (Labelling and Advertising) Regulations 2026, each flavour carries its own ingredient list and declarations, so every flavour change is also a label change. A sequence that keeps similar packs together reduces the chance of a wrong reel reaching the wrong powder, which is the error the label-clearance check exists to catch.
Which parts of a changeover can the buyer take off the clock?
Most of them. The lean method known as SMED, single-minute exchange of die, splits setup into internal work that can only happen while the machine is stopped and external work that can happen while it runs (Lean Enterprise Institute). Anything a buyer settles before the block becomes external, so the stopped time covers only the swap itself.
Shigeo Shingo’s original target was a changeover in single-digit minutes. A food line with a validated clean will not get there on a flavour change, but the principle still pays. Five inputs, ready before the block starts, take the most waiting out of a stick-pack changeover:
- All powders delivered, released and weighed into batches before the block date, not arriving on the day.
- Every printed reel on site and checked against the approved artwork for each flavour.
- One stick width and length across the range, so no forming parts change mid-block.
- One fill weight across the range where the market allows it, so dosing is reset once.
- The flavour order agreed in advance, so the planning team can schedule the clean types.
Printed laminate is the input most likely to be missing. SFC’s working plan for a first printed pack runs 8 to 13 working weeks from dieline to material in the plant, against one to two weeks of co-packing lead time from arrival of finished goods. A block booked before the film arrives is a block released and rebooked, which is covered in more detail in artwork and print lead time for private label.
When is a short run still the right call?
A short run is right when the brand is testing a flavour, a channel or a price, and the cost of unsold stock exceeds the extra line cost per stick. Paying LKR 2.80 a stick instead of LKR 1.36 on 10,000 sticks costs about LKR 14,400 more in this example, which is often cheaper than holding 40,000 sticks nobody reorders.
The comparison works in cash terms, not unit terms. In the example, a 50,000-stick run of one flavour costs LKR 68,000 of line time and puts 50,000 sticks of powder, laminate and cartons into a warehouse. A 10,000-stick run costs LKR 28,000 and commits a fifth of the materials. For a first listing, a smaller commitment that sells through can beat a cheaper unit that does not.
The trap sits in the middle. Five flavours at 10,000 sticks each is 50,000 sticks, but with five changeovers it carries 7.5 hours of stopped time instead of 1.5. In this example that range costs LKR 140,000 of line time against LKR 68,000 for 50,000 sticks of one flavour. The minimum order quantity by format post sets out the cash each format ties up at first run; the changeover count is the variable that turns a sensible launch into an expensive one.
Where SFC walks away
A range of many flavours, each too small to cover its own changeover, booked as separate small blocks across the month.
A block booked before printed film is confirmed on site.
A powder still being reformulated: that is an R&D brief, 3 to 4 weeks at most from signed brief to approved formulation, and it comes before a packing slot.
How does Silk Foods Ceylon price a stick-pack block?
SFC books co-packing as a production block, typically a single day, and quotes in LKR per 1,000 packs or per kilogram. The quote reflects run length, number and type of changeovers, fill weight, film supply and compliance scope. Lead time is one to two weeks from arrival of finished goods. There is no published per-stick price, because the changeover count moves it most.
Seasonal demand matters too. The Central Bank’s September 2026 PMI found manufacturing expanding for food and beverages, with suppliers’ delivery times still lengthened. Year-end demand fills shared lines early, so a consolidated block booked ahead is easier to schedule than several small ones requested late, as set out in festival-season co-packing slots. For the wider principle of holding a range to one pack spec, see how standardised packaging cuts cost per unit.
Frequently asked questions
Why does a small stick-pack run cost more per stick?
The changeover is a fixed cost shared by every stick in the run. In a worked example with a 90-minute changeover and an LKR 12,000 line hour, changeover adds LKR 1.80 per stick on 10,000 sticks and LKR 0.18 on 100,000. Filling cost per stick stays roughly the same at both run lengths.
Which stick-pack change takes the longest?
A change of stick width or length is usually the slowest, because forming tubes, slitter and cutter settings change. A full clean between a strong or allergen-containing powder and a mild or allergen-free one is next. A print change on the same film and powder is the shortest, mainly a reel swap and a label-clearance check.
How can a brand reduce changeover cost with Silk Foods Ceylon?
Keep one stick width and one fill weight across the range, agree a mild-to-strong flavour order, and have every powder and printed reel on site before the block. Silk Foods Ceylon (SFC) books co-packing as a production block, typically a single day, with one to two weeks’ lead time from arrival of finished goods.
What does the BRCGS Food Safety Standard require at a product changeover?
Clause 6.2.2 asks for a documented check at each product change confirming that the previous run’s printed packaging and labels have been removed from the line, as summarised by ASC Food Safety in 2026. The check applies at every change, so a range with more variants carries more checks.
How Silk Foods Ceylon can help
For drink and seasoning brands planning a multi-flavour stick-pack range, Silk Foods Ceylon (SFC) runs co-packing at its 10,000 sq ft cellular-manufacturing facility in Matale. The buyer supplies the powder and film or asks SFC to source film; the SFC team plans the flavour sequence, fills, seals, codes and labels, and reviews artwork against the Sri Lanka Food Act framework with SLSI submission support. Blocks are typically a single day, with one to two weeks’ lead time from arrival of finished goods, on a BRCGS- and FSSC 22000 V6-audited site. Where the powder still has to be made, the spray-drying line and the in-house R&D team sit on the same site. More on the service is in co-packing in Sri Lanka.
To brief a stick-pack block, email b2b@esilkroute.com.lk or call +94 76 441 0389 / +94 76 918 5744.
Sources
Central Bank of Sri Lanka, SL Purchasing Managers’ Index (PMI), September 2026: PMI Manufacturing 53.0, unchanged from August; expansion in new orders and production attributed largely to food and beverages and textiles and wearing apparel; suppliers’ delivery time lengthened. Published 15 October 2026. Retrieved 22 October 2026. https://www.cbsl.gov.lk/sites/default/files/cbslweb_documents/press/pr/press_20261015_sl_pmi_2026_september_e.pdf
Lean Enterprise Institute, Lean Lexicon, “Single-Minute Exchange of Die (SMED)”: definition, the single-digit-minute target and Shingo’s split of internal and external setup. Retrieved 22 October 2026. https://www.lean.org/lexicon-terms/single-minute-exchange-of-die/
ASC Food Safety (2026), “BRCGS for Food Safety Changes, Part 6: Process Control”, on clauses 6.2.2 and 6.2.3 (label and packaging checks at product changeover and during the run). Retrieved 22 October 2026. https://ascfoodsafety.com/brcgs-for-food-safety-changes-process-control/
Government of Sri Lanka (2026), Food (Labelling and Advertising) Regulations 2026, Gazette Extraordinary No. 2494/47, 26 June 2026, made under the Food Act No. 26 of 1980. Retrieved 22 October 2026. https://documents.gov.lk/view/egz/2026/6/2494-47_E.pdf
Silk Foods Ceylon, internal capability data for the Matale facility: co-packing booked as a production block, typically a single day; lead time one to two weeks from arrival of finished goods; first printed pack plan 8 to 13 working weeks; R&D 3 to 4 weeks maximum. The LKR line-hour, line-speed and changeover figures in the worked example are illustrative assumptions for the arithmetic, not SFC rates.
Written by the Silk Foods Ceylon Team. Silk Foods Ceylon (Pvt) Ltd. is a BRCGS- and FSSC 22000 V6-audited contract manufacturer in Matale, Sri Lanka, offering contract manufacturing, private labelling, co-packing, and in-house R&D for local Sri Lankan brand owners, FMCG companies, hotel and restaurant groups, and distributors. To brief a project: b2b@esilkroute.com.lk, +94 76 441 0389, or +94 76 918 5744.
