Industry
Part of Sweater mending how it works: a step-by-step guide
Sweater mending with reclaimed wool and unlabeled knits: what you are holding, explained properly
Sweater mending makers: how recycled wool is described on labels under FTC rules, why it behaves differently, and how to test unlabeled knits.
Sweater mending makers who repair sweaters for long end up working on garments whose fiber content is a guess.
Labels wear off, thrifted knits arrive bare, and stash yarn has no band. The Federal Trade Commission (FTC) enforces labeling rules under the Textile Fiber Products Identification Act and the Wool Products Labeling Act, and these rules guide what you are holding, though no practitioners were interviewed.
What to take away
- Reclaimed and recycled wool has shorter fibers than new wool, and it is typically weaker and pills sooner.
- Test unlabeled knits before repairing: a burn test on one strand and a wash test on a swatch.
- Treat unknown as a label in its own right, and write it on the storage bag.
Recycled wool is genuinely different
Wool that has been through a previous fabric has been cut, carded and respun, and its fibers are shorter as a result. Short fibers make a yarn that pills sooner, breaks more easily under tension, and holds a darn less well. This is a well-known characteristic of recycled wool.
Under the Wool Products Labeling Act, 16 CFR § 300.28 (the section on undetermined quantities of reclaimed fibers), where a wool product contains man-made fibers recovered from other textile products in undetermined quantities, the percentages may be disclosed in aggregate.
List man-made fibers followed by fiber names in order of predominance by weight. Example: 60 percent wool and 40 percent man-made fibers listed as rayon, acetate, nylon.
An aggregate disclosure like that is a signal. It means nobody measured the individual proportions, and your repair yarn choice is a judgment rather than a match.
Products made from scrap
Under the Textile Fiber Products Identification Act (16 CFR Part 303), garments manufactured from miscellaneous cloth scraps may carry a disclosure that states the predominant fiber and a minimum percentage of recycled wool—for example, 'miscellaneous cloth scraps composed chiefly of cotton with a minimum of X% recycled wool.' The rule covers products made from manufacturing by-products with various fibers in undetermined percentages.
Scrap like that is exactly where repair-led makers start, and the labeling rules for it are looser than most buyers assume.
That wording exists because scrap-based manufacture is normal. It also tells you what to expect from such a garment: uneven fiber behavior across the same piece, which is why a patch that matches in one place can look wrong two inches away.
Testing an unlabeled knit
- Pull one strand from a seam allowance and burn it. Wool self-extinguishes and smells of burning hair; acrylic melts and beads; cotton burns fast and leaves soft ash.
- Wet a small area and pull it. Wool weakens noticeably when wet; acrylic does not change.
- Rub the surface briskly. Wool starts to felt; acrylic pills instead.
Three tests, five minutes, and you know enough to choose yarn.
Working with what you have
If the fiber is wool and the yarn is reclaimed, expect a repair that needs revisiting sooner. Work the darn slightly larger than the damage so the load spreads further into sound fabric, and accept that the area may pill.
The sequence itself does not change, and the Swiss darning method (our step-by-step guide) applies, but the support you work on matters more with weaker yarn because any stretching does lasting damage.
