We are happy to give help and advice on how you can prepare your fleeces for successful processing.
The Art of Fibre website also has lots of useful advice on best practice for shearing and fleece skirting.
We use just the blanket fleece to make worsted yarns – neck fibre is sometimes suitable but rarely as good as the blanket from the same animal.
To make the best yarns we try to batch fibre with the least variation in staple length, fineness and handle.
Fibre Properties for the Worsted Process
Staple length
- Average shorn fibre length should be 9 – 20cm (3½” – 8”)
- Shearing which closely follows the contours of the skin will avoid cutting the staples too short and with different lengths
- Coarser fibres, suri fibre and fibre for weaving yarns should ideally be longer than finer fibres, huacaya fibre and fibre for knitting yarns.
- Variation : average fibre length should vary by less than 4cm (1½”) within a batch for best results.
Fineness
- Fleece with average fibre diameter < 26 microns will make a soft yarn (depending on staple length).
- Coarser fibres are better made into heavier yarns and may benefit from blending with other natural fibres
- Fleeces with SD < 5.5 micron and comfort factor > 95% make the best yarns. (refer to AAFT for guidance on fibre statistics).
- Variation : average fibre diameter should vary by less than 3 microns within a batch for best results.
Contamination
- Coarse fibres : separate leg and neck fibre from blanket BEFORE bagging fleece to avoid mixing – fleeces with lots of guard hair will not make good yarns.
- Colours : keep coloured fleeces strictly separate – especially black and white !
- Vegetation : remove worst and most obvious material – carding and combing remove the rest
- Also try to avoid short 2nd cuts and its not good to have stones, toenails or faeces in the bags either !
Storage
Dry fleece in clear plastic bags loosely sealed to exclude moths stored in cool dry conditions will be usable for several years.
Worsted Processing
The worsted process was developed long ago and has proved very effective for long staple speciality fibres such as alpaca and mohair.
The multiple stages produce a yarn which is clean, compact, even and strong, ideal for hand / machine knitting or weaving.
Combing aligns the individual fibres to enhance softness and the reflection of light from the yarn surface which is particularly beneficial for alpaca, both huacaya and suri.
The essential stages in the process are:
- carding – opens the locks and separates the fibres to create a sliver of loosely held, roughly aligned fibres.
- preparation gilling – multiple ends of sliver are fed into a gill machine which delivers a single sliver at a specified weight with improved evenness and fibre alignment. Several passes through the gill prepare the sliver for combing.
- combing : this is the unique feature of the worsted process. Multiple ends of gilled sliver are fed into the comb – an ingenious machine which in various forms has been around for over 100 years. The fibres are drawn through fine combs which remove selected short fibres, neps (random bundles of short fibres) and any remaining vegetable matter. Most importantly the long fibres are aligned to lie parallel in the delivered sliver and this is what produces the very desirable properties of a worsted yarn.
- finish gilling : the combed sliver is weak so several passes through the gill improve its strength to make a very uniform top sliver of highly organised long fibres.
- drawing and doubling : the tops are drawn finer in several stages. Two or more ends from the previous stage pass through the machines together (known as doubling) to make a lighter, more even end. A small amount of twist is applied to help carry the fibre through each stage. The final output is very even, lightly twisted roving at 1 – 2g/m on a bobbin.
- spinning and twisting : the roving is drawn finer on a ring spinning frame and more twist added to achieve the desired strength and softness. Two or more singles can be twisted together in the opposite direction to make yarns from very fine 2-ply to DK weight.