Why Jeans Need a Staged Sampling Process
A T-shirt can often be approved on one or two samples. Jeans rarely can. The garment has a complex pattern, several fabrics and trims, a wash that changes the look and measurements, and a size run that must grade properly. A mistake in any one of these areas can be expensive to correct after cutting. The sampling process exists to find and fix each type of problem at the cheapest point, which is before bulk fabric is cut.
The staged approach also protects the relationship with the factory. Specific, stage-by-stage comments are easier to act on than a general "not right". Our general garment sampling process guide explains why sampling is a common failure point for new brands, and this guide narrows that to denim.
The Stages at a Glance
Factories and brands use different words, and the same sample can be called by two names. What matters is that each stage has a defined purpose and a clear approval. The sequence below is a common one for a new style.
- 1Development sampleFirst interpretation of the design and tech pack. Checks the idea, pattern and fabric.
- 2Fit sampleChecks fit and measurements against the spec on a body or form.
- 3Wash sampleApproves the wash look: shade, whiskers, hand feel, shrinkage.
- 4Size setChecks grading across the size run, usually smallest, middle and largest.
- 5PP sampleMade from bulk fabric and trims. The reference for production.
- 6Top of productionChecks early production pieces against the approved PP sample.
Development Sample: Does the Idea Work?
The first sample turns a sketch, reference garment or tech pack into cloth. At this stage the fabric may be a close substitute and the wash may be a rough guide, and that is fine. Look for the overall proportion, pocket shapes, stitch details, hardware and general feel. This is the time to catch design problems, such as a pocket that sits too low or a leg that twists, before spending on finer points.
The quality of the tech pack sets the quality of this sample. If the specification is vague, the first sample reflects the factory's guess. Read the jeans tech pack guide and the tech pack how-to before you send a brief.
Fit Sample: Measurements and Body
The fit sample is where the garment is measured and tried on. Measure the sample against the specification at every point of measure: waist, hip, front and back rise, thigh, knee, leg opening and inseam. Then try it on a fit model or a form and judge how it sits, which no table of numbers can show. Rise, seat shape and thigh room are the classic problem areas, as discussed in the jeans rise guide and the jeans fit guide.
Specific groups of buyers will have different priorities. A women's range will pay close attention to waist-to-hip proportion and stretch behaviour, covered in our women's jeans fit and sizing guide, while a men's range focuses on thigh, seat and leg shape, as in the men's jeans guide.
Always say whether measurements are taken before or after washing. A sample measured unwashed and then washed can move by a visible amount, so the spec should define the point at which the measurement counts. The measurement conventions are in the jeans size chart and measurement spec guide.
Wash Sample: Shade, Finish and Handle
The wash sample approves the look. Denim can be washed and finished in many ways, from light rinse to heavy stone and enzyme treatments, and from hand scraping to laser and ozone. The same fabric can look completely different depending on the recipe, so the factory needs a reference such as a physical garment or an approved swatch.
When reviewing a wash sample, look at five things: overall shade against the reference, contrast between high and low areas, whisker and honeycomb placement if present, hand feel, and the condition of seams, pockets and trims after washing. For heavier washes, the garment strength and abrasion points need a close look. See the denim washes guide, the laser and ozone finishing guide and the distressed jeans guide.
Approve the wash on garments that went through the full process, not on a swatch or a hand-treated piece. Hand-finished showpieces often look better than machine-washed bulk, so ask which method was used and whether it can be repeated. Agree the colour standard in a form that can be physically compared by the factory throughout production.
Size Set: Does the Grade Hold Up?
A style that fits in one size may fail in others. A size set is a set of samples in several sizes, normally the smallest, a middle size and the largest, made with the same pattern, fabric and wash. Compare measurements across sizes against the grading rules, and check the proportions by eye. Pockets, rise and leg shape should look right in each size rather than simply scaled.
This is also the point to check that the wash is consistent across sizes, because large and small garments can wash differently in a machine load. Grading logic is described in the garment grading and size chart guide. If a size set is skipped to save time, any grading problem becomes a bulk problem.
Pre-Production (PP) Sample: The Reference for Bulk
The PP sample is the most important approval. It should be made from the real bulk fabric and trims, with the final wash, labels and packing details. It is the sample that production is compared to, and its approval authorises cutting. Make sure the factory states which fabric lot was used and check that the fabric has passed any required tests. For fabric checks see the denim fabric inspection guide and the denim fabric testing guide.
Review the PP sample against the full specification, not only the fit. Check the fabric lot and weight, the shade against the signed standard, the trims and hardware, the labels and care label, the stitches and tolerances, and the packing method. Check any shrinkage test results. After approval, send a signed copy to the factory and keep a matching one. Anything that changes after this point, such as a different fabric lot or trim supplier, should go through a documented change.
Top of Production and Shipment Checks
The top of production (TOP) sample is taken from the first finished production pieces. It confirms that bulk matches the approved PP sample, and it is reviewed before the rest of the goods are packed. Differences found at this stage are cheaper to fix than at final inspection. Compare shade, measurements, trims and finish with the PP sample, then record the outcome. Final inspection follows, as described in our jeans quality inspection checklist and the AQL inspection guide.
Writing Sample Comments the Factory Can Use
Good comments are specific, measurable and tied to the spec. Poor comments are adjectives. The table gives an example format, using invented figures to show the structure.
| Area | Weak comment | Useful comment (illustrative figures) |
|---|---|---|
| Waist | Too tight | Waist measures 1.5 cm under spec. Correct to spec in the pattern, not by washing. |
| Rise | Rise looks wrong | Front rise is 1 cm over spec. Reduce by 1 cm and keep the back rise unchanged. |
| Wash | Too dark | Face is darker than the signed standard in the mid-thigh area. Match the standard under daylight. Send a revised wash sample. |
| Leg | Twisting | Outer leg seam rotates forward after wash. Check grain direction and seam allowance, then confirm after a wash. |
| Hardware | Not premium | Rivets show surface marks. Replace with the approved supplier part and confirm in a photo. |
Use photographs with arrows and measurements, refer to the point of measure code on your spec, and number every comment so the factory can answer them one by one. Send comments in one consolidated list rather than as scattered messages, and ask the factory to reply in the same format. This reduces the risk of a point being lost. Attach the current size chart and tech pack version to every round, so the factory and your team are always reading the same document.
Using Photos, Video and Courier Wisely
Photographs and short videos speed up many reviews, and they are useful for checking construction, placement and general appearance. They are poor judges of shade and handle. Colour on a screen depends on the camera and the display, and a flat photograph cannot show how a fabric drapes or how stiff it is. Use digital review for early rounds and for quick checks between samples, then insist on the physical garment for wash, fit and PP approval. Courier time is part of the schedule, so plan it as a step of its own: a sample that takes several days to arrive and several more to review can easily add a week to each round.
When a physical sample is not practical, ask the factory for a measured photo set with a tape visible in each image, a video of the garment on a form, and a swatch of the washed fabric sent separately. None of these replaces the physical sample, but together they reduce the number of rounds spent on avoidable errors.
Approval Records and Version Control
Every sample should have an identity: style, version, date, fabric lot, wash code and the status of the comments. A simple sample log, kept in a shared spreadsheet, prevents the common problem of two versions in circulation. Record who approved, on what date, and what changed since the last round. Store photographs and measurement sheets with the log.
Timeline and cost need the same discipline. Sample rounds take time, and every extra round delays bulk. Our denim production lead time guide shows where sampling sits on a calendar, and the jeans costing sheet helps you account for sample charges. Ask each supplier how many sample rounds are included and what each further round costs, because policies differ.
Common Sampling Mistakes
- Approving fit on an unwashed sample. The wash changes the measurements.
- Skipping the size set. Grading problems then appear in bulk.
- PP sample made from substitute fabric. It no longer represents bulk.
- Vague comments. Adjectives get interpreted, measurements get fixed.
- No signed standard. Shade disputes become matters of opinion.
- Changing the specification after PP approval. Undocumented changes cause most disputes.
- Sample sequence and names agreed in writing before the first sample
- Tech pack complete and version-controlled
- Fit sample measured against spec and tried on a body or form
- Measurement basis (before or after wash) stated
- Wash standard signed and held by both sides
- Size set reviewed for grading and wash consistency
- PP sample made from bulk fabric, trims and final wash
- Fabric lot and test results recorded with the PP approval
- Comments numbered, measured and photographed
- Top of production checked against the signed PP sample
Jeans Sampling Process with Ruhrose
Ruhrose runs the jeans sampling process as part of denim development, with development in Bangladesh and UK buyer support. Each stage has a written purpose, a numbered comment list and an approval record, and the PP sample is made from the bulk fabric before cutting. Production starts from 500 pieces per style and colour. For the route around sampling, see how to get jeans manufactured. To brief a new style, start a product enquiry with your tech pack or reference garment.