The purpose of a pre-shipment test is not to prove the material is good. It is to prove the material is the same as the one you approved, and to catch the change before it becomes a container.
The minimum set
| Test | Method | Acceptance |
|---|---|---|
| Compression recovery | internal 5 kg / 24 h / 40 C | >= 90 % |
| Peel strength (laminated) | ISO 2411 | >= 6 N/50 mm |
| Pilling | ISO 12945-2 | >= grade 3-4 |
| Colour fastness to rubbing | ISO 105-X12 | >= grade 4 dry, >= 3-4 wet |
| Dimensional change | ISO 6330 / ISO 5077 | <= 3 % |
| Air permeability | ISO 9237 | report value, no pass/fail |
Why each test earns its place
Compression recovery. Run to internal 5 kg / 24 h / 40 C, acceptance >= 90 %. This is the test that answers the question the buyer will ask first, and the one where a supplier is most likely to send a development sample rather than production material.
Peel strength (laminated). Run to ISO 2411, acceptance >= 6 N/50 mm. This is the test that answers the question the buyer will ask first, and the one where a supplier is most likely to send a development sample rather than production material.
Pilling. Run to ISO 12945-2, acceptance >= grade 3-4. This is the test that answers the question the buyer will ask first, and the one where a supplier is most likely to send a development sample rather than production material.
Colour fastness to rubbing. Run to ISO 105-X12, acceptance >= grade 4 dry, >= 3-4 wet. This is the test that answers the question the buyer will ask first, and the one where a supplier is most likely to send a development sample rather than production material.
Sampling for 3D mesh, and where it goes wrong
A single sample from the top of a roll tells you about the top of that roll. For a first order of 3D mesh, take three positions along the run and one sample per colour, then test compression recovery on all of them rather than on a composite.
Condition the samples before testing. Several 3D mesh results move by 10-20 % between a dry laboratory and a humid one, which is why two labs can disagree on the same material without either being wrong.
Reading a 3D mesh report properly
- The measured value for compression recovery, not only the verdict. A pass at >= 90 % is a risk, not a comfort.
- The method number for peel strength (laminated), not the description. A trade name is not a method.
- Conditioning and duration, because both change several results in this family.
- Sampling position and lot number, so the result can be tied to the cartons you received.
- The laboratory name and its accreditation, if the report may be used in a dispute.
The three tests buyers skip and regret
First, the test that reproduces the end use rather than the laboratory condition. For 3D mesh that usually means peel strength (laminated) measured after the wash or exposure the product will actually see, because compression set does not appear in a conditioned laboratory.
Second, the test on the assembled product. Flat goods can pass every check and still fail at a seam, a fold or a fixing point. Delamination is usually a construction failure rather than a material one.
Third, retention. Keep one sealed sample per approved lot, labelled with the lot number and the date, for at least two years. It is the only way to know whether compression recovery changed or the conditions did.
Turning test results into a purchase order clause
Write the acceptance value into the PO, name the method, and state what happens on failure: replacement, credit, or rejection at whose cost. A test without a consequence is advisory, and advisory tests get skipped when the schedule is tight.
Full parameter ranges are on the 3D mesh page; the checks that hold those ranges in production are described on the quality control page.
Questions buyers ask before ordering
Can you supply 3D mesh under 200 m per colour?
We can, at a small-lot surcharge, because beam setup and dyeing are the fixed cost. Below 100 m we usually quote from stock shades instead of custom dyeing.
Does thickness tolerance matter?
Yes. +/- 0.5 mm is normal; +/- 1 mm changes the sewing allowance and the compression figure. Ask for the tolerance in writing.
Is 3D mesh machine washable?
Spacer knits tolerate 40 C domestic washing if the face is tricot and the edge is bound. Laminated versions depend on the adhesive, not the mesh.
How often to re-test
| Stage | What to test | Frequency |
|---|---|---|
| Development sample | All parameters in the specification | Once per development |
| First production lot | All parameters, plus the end-use test | Every lot for the first three |
| Repeat lots | Critical parameters and the one that failed before | Every lot |
| Annual | Full panel, including ageing where relevant | Once a year, or after any process change |
The rule behind the table is simple: test most when you know least. A supplier with three clean lots has earned a lighter regime; a supplier with a process change has not, even after five years.
Retained samples: the cheapest insurance in the order
Keep one sealed sample per approved lot, labelled with the lot number and the date, for at least two years. It costs a shelf. It is also the only way to answer the question that decides most claims: did the material change, or did the conditions?
Without a retained sample, a claim becomes an argument about memory. With one, it becomes a measurement, and measurements get resolved.
For 3D mesh, the sample should include the finish, not just the base material, because compression set usually starts in the finish or the additive rather than the substrate.
The test plan for 3D mesh, by order size
| Order | Tests to run | What it establishes |
|---|---|---|
| Sample or trial | Compression recovery | Whether the material can meet the requirement at all |
| First production order | Compression recovery, Peel strength (laminated), Pilling | The baseline every later lot is compared against |
| Repeat orders | Compression recovery plus the parameter that failed last time | Whether the process has drifted |
| Annual or after a process change | Full panel | That nothing has moved in the background |
Testing more on a repeat order is waste; testing less on a first order is a gamble. The table is deliberately asymmetric, because the risk is. For 3D mesh, the one test never worth dropping is compression recovery, because it is the one that predicts compression set.
From quotation to specification in seven lines
Leave the tolerance and the method out and every dispute is settled by whoever needs the goods more.
- Monofilament diameter: 0.08-0.20 mm is not an answer on its own. Ask for the last three lots’ actual readings and the spread behind them.
- Usable width: agree the test method with the number. Two labs, two methods, two answers, one argument.
- Surface construction (tricot / plain / mesh): state where in the band this order sits. The middle of the band is not what a tolerance is for.
- Colour fastness to rubbing: the figure you will accept inside the >= grade 4 band, the tolerance on it, and the method used to measure it.
- Sample retention: one production sample per lot stays with the mill for twelve months. Claims are settled against it, not against memory.
- Test reports: name the standard as well as the test. A pass on a development sample is not a pass on a production lot.
- Deviation rule: anything outside the agreed bands is reported before shipment, not after arrival.
Questions worth asking before the price is agreed
The questions below are the ones that cannot be answered from a catalogue, which is exactly why they are worth asking.
| Question | Answer that should worry you | Answer that holds up |
|---|---|---|
| Who signs the test report, and against which standard? | “Our QC department signs it.” | A named standard, a named method and a signature that belongs to somebody who can be asked again next year. |
| How do you hold usable width inside 150-160 cm? | “That is standard for us, no problem.” | The last three lots’ readings, the instrument used and who signs the report. Delamination starts here. |
| What happens if colour fastness to rubbing misses the >= grade 4 requirement? | “It will not happen.” | A re-test clause, the tolerance on the re-test, and the point at which the lot is remade rather than discounted. |
Need a test plan for a first order?
Send the end use, the quantity and the destination market, and we will come back with a specification that meets it, a price at your volume and the test reports that back it up. Samples are free for qualified programmes; we charge the courier only.
Related reading
Sample cut with your values on it · Neutral packing and private label · Consolidation, documents and lead times
