A Camping Brand’s First 5,000 Sachets: Fill Weight, Carton and Cost

The brief arrived as a single line: “25 g sachets, 5,000 units, our logo, ready for the spring range.” The brand had a good position in lightweight stoves and a founder who had used gel sachets on a bothy trip. What they did not have was a fill weight that matched how their customer actually uses a toilet in the field, and that one number drives the rest of the costing.

Sachet projects fail on arithmetic more often than on chemistry. Here is the arithmetic, laid out the way a buyer will eventually ask for it.

Choosing a fill weight that matches one use

A trail toilet session produces 250 to 400 ml of urine. A 25 g sachet of a mid-range SAP blend absorbing 180 times its weight in urine handles about 4.5 litres in a laboratory beaker, which sounds like enormous headroom until you account for the bag. In a 1-litre collection bag with 300 ml of urine, 2 g is enough. In a 5-litre bucket shared by a family over a weekend, 25 g is about right. In a 20-litre portable tank, you need 60 to 80 g and a sachet is the wrong format entirely.

So the fill weight question is really a container question. Brands that sell into ultralight hiking want 8 to 12 g, sized to one bag. Brands selling family camping kits want 20 to 30 g with instructions covering a bucket or a cassette. Getting this wrong produces the worst outcome in retail: a product that works but is used at a fifth of the intended dose, and a customer who concludes it does not work.

The carton is where the cost hides

Film and fill are cheap at volume. Cartons, artwork, and the labour of counting are not. A 5,000-unit run packed 50 per carton gives 100 cartons, which is manageable for a small warehouse but expensive per unit at the printer. Packed 100 per carton, the print run halves in cost per box and the cube drops by roughly a third, because the folding carton wall thickness is amortised over more units.

The trap is display-ready packaging. A retail-ready tray that goes straight onto a shelf costs two to three times a plain carton and constrains the pallet configuration. If the brand’s first channel is a website and a few independent outdoor shops, ship plain cartons and let the shop merchandise from a counter box. Add the display tray in year two, when a chain asks for it, and expect to redo the artwork dieline at that point.

What to fix in the brief before the factory quotes

Four specifications decide whether the quote you receive is the quote you can use. Film structure, usually a metallised or aluminium-laminated layer if the sachets will sit in a damp pack for a season. Tear notch position, because a sachet that needs teeth in the rain gets cut open with a knife and half the powder goes on the ground. Lot code and best-before placement, which must survive condensation. And the artwork safe area, which on a 60 by 90 mm sachet is smaller than most designers expect.

One brand we worked with printed dosing instructions at 5 pt in four languages, and the field feedback was blunt: nobody could read it with cold hands. They moved to a pictogram strip — one bag icon, one bucket icon, a number — and support tickets about “how much do I use” fell away almost entirely.

The failure that costs a season

The expensive mistake is not a bad fill weight. It is a film that fails in transit. A pallet of sachets shipped in a container through a humid summer can arrive with powder caked into bricks inside intact-looking film, because the water vapour transmission rate was adequate for a warehouse and inadequate for a six-week sea voyage. If the goods cross an ocean, specify the WVTR and ask for a sample that has been through a humidity chamber, not just a room-temperature shelf test.

Before the purchase order goes out, write three lines on one page: grams per use case, units per carton, and film specification with a vapour barrier figure. Everything else — logo placement, colour, the story on the back — can change later without touching tooling. Those three cannot. The SAP powder product range gives the absorption figures you need to convert a use case into a fill weight, and the conversion is worth doing before a designer touches the artwork.