4.1.6 Crutching Sheep

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Crutching is the removal of wool from around the tail and udder of the sheep to prevent flystrike, to make it easier for newborn lambs to feed and to prevent dags forming.

Figure 4.6 Crutching

Pre-Lamb - Remove a full or half belly then proceed to the full crutch.

Half belly

Option 1 - With any belly crutch the teats must be properly cleared so lambs can feed easily.


Figure 4.6 Crutching

Figure 4.6 Crutching
Option 2

 

Full Belly - The full belly is recommended with long woolled sheep. This helps the fleece dry quickly keeping the wool a better colour. It also gives the option of leaving very short belly wool on in the case of early mainshear.

Note: Keep the comb on the skin up to the base of the teats. Don't flick the comb off the skin.

It is important that the whole crutch is properly cleaned.

Note: Remember to protect the teats.

Figure 4.6 Crutching Figure 4.6 Crutching

The back end can be done in two ways.
Figure 4.6 Crutching


E. Fan Crutch - Special care must be taken to avoid cutting hamstrings.
Use left hand to maintain pressure in the flank to keep the sheep's legs
straight until both hamstrings have been cleared.

Figure 4.6 CrutchingF. Back Slam.

Figure 4.6 Crutching

Figure 4.6 Crutching G. The back end must be even on both sides without an overhand of wool over the tail. Excess fleece wool should not be removed. A tidy finish is essential. Some trimming blows may be needed to ensure no tassles of wool hanging from the sheep.

Figure 4.6 Crutching
I. Wethers - When clearing the pizzle, always approach from the side.

 

H. Top Knot (where necessary)

 

Source: Wools of New Zealand

4.2 Combing

4.2.1 Combing Cashmere Goats

Cashmere fibre is combed from the animal during the spring moult. The cashmere goat is tethered in a standing position and the longer outer hair is first clipped to remove matted hair to make it easier to comb. It is then tethered lying down for combing which is done in short, pulling strokes. Finally, the animal is clipped once more to remove the remaining hair which also has export value (for use in suit interlinings and carpet underlay).

Combing is a more efficient way of harvesting the fibre than shearing, which is the method favoured in the West. Shearing not only means that all the coarse fibre is collected together with the down, but it may fail to harvest all the underwool, leaving some of the precious fibre on the animal. The comb has been copied in the West but has proved difficult to use.

Traditionally, farmers collected and packed the fibre into jute sacks; today polypropylene sacks are more common. Unfortunately, this presents the possibility of contamination of the cashmere with stray fibre from the sacks. Each sack should be new to reduce this chance and it is vital to maintain cleanliness in the packing of the fibre. A small strand of synthetic fibre which escapes notice before processing can be very costly to remove.

Polypropylene cannot be dyed and if fibre contaminates cashmere yarn, it will ruin the processing lot. One large supplier of dehaired cashmere is initiating a programme of exchanging polypropylene bags for polyethylene bags, to reduce contamination.

The sacks of cashmere are delivered to local collecting stations which exist throughout the cashmere producing regions of China. (There are 60 collecting stations in Gansu province alone). From these initial collection points, the sacks of fibre are distributed to sorting factories or warehouses.

 

 

4.2.2 Combing Yaks

Yaks are combed soon after the spring moult has occurred. The lower sides and belly are combed to remove the soft fine under coat. The neck, back and hind quarters are not combed.

4.3 Plucking Angora Rabbits

Plucking is an alternative to shearing. It's not really feasible in a commercial rabbitry as it is time consuming - one rabbit taking about an hour to pluck. For a small scale venture seeking top quality fibre, plucking is suitable.

Plucking must be done during the rabbit's natural shedding period. Young rabbits are first plucked at about 12-14 weeks. Thereafter every three months.

Judging when a rabbit is ready to pluck is developed through experience. With a coloured rabbit, colour is usually the best indicator. Part the fibres, and if new darker growth can be seen at the base, it is ready for plucking.

When the fibre is ready for harvesting the old coat lightens in colour, and the new fibre is about 33-50 mm long. The fibre to be plucked will be about 100 mm long.

White fibre is more difficult to judge. To test whether a rabbit is ready gently pluck a sample out. Once plucked, the rabbit will look quite naked.

Pluck the long fibres by gripping the tips of the fleece between finger and thumb. Use the fingertips of the other hand to hold the rabbit's skin tight. Only take the long fibres, and remove small amounts of fibre at a time. Don't attempt to pluck them unless the fibres are loose, as this will cause the rabbit discomfort.

The plucked fibre should be packed in a non-contaminating packaging material and suitably identified. Plucking often needs to be done over a period of days as the fibre may not all be ready for plucking at the same time. Generally, the back is ready first, then the sides and later the extremities.

4.4 Slipe Wool Production

There are many millions of sheep slaughtered throughout the world for their meat. The process obviously requires each carcass to have the skin removed. This skin offers two valuable bye products for the sheep meat industry - the pelt for leather and the wool. For the full potential value of both the pelt and the wool to be realised requires the woolly skin to be processed correctly. This section deals with both the process of removing and processing the wool (known as slipe wool) and first stage treatment of the pelt once the wool has been removed.

Slipe wool, which constitutes approximately 5% of world wool production, has particular characteristics that arise from the sliping process and which make it somewhat different from greasy wool. The three most notable of these are that:

1. Because the skins receive a thorough washing immediately after removal from the animal, much of the suint is washed from the wool and the yield on drying raised, on average, about ten percent.

2. Fibre length is more even because without shearing, there are no second cuts.

3. Residues of the depilatory mix may be found as a contaminate in the wool. Colloquially known as "lime", this is a dried compound of the lime-sodium sulphide depilatory and some dissolved wool fibre that it contacted. This is fairly readily broken up and removed in scouring.

4.4.1 The Production System

The text will name the steps in the production line and give a brief explanation of the method and purpose of each. It is important to bear in mind that the system outlined is aimed at having two valuable products both emerging in the best possible condition: the pelt and the wool.

Some side processes will be described separately. When introduced in the text, these will be names between square brackets thus: [Slipemaster process].

4.4.2 Sheep Wash

It is recommended that incoming sheep are washed in a spray, swim-through or submerging floor wash to free them of any dirt and particularly fouling that occurs during trucking. This is done the day before slaughter.

4.4.3 Skin Wash

As skins arrive at the fellmongery (often within seconds of leaving the animal), they are thoroughly washed in cold water to:

(a) quickly lower the temperature by removing the body heat and,

(b) to remove grime and particularly blood from the wool.

If skins are left uncooled and in bulk, decay will set in quickly and spoil the leather-making qualities. In plants without their own fellmongery, the skins are washed before dispatch to the company's central fellmongery. Washing is usually by being propelled through a soak tank and then tumbled in a rotary screen in a spray of water. This device is colloquially known as a "rumbler".

4.4.4 Wringing

Subsequent procedures need the skins wet but not as wet as they emerge from the skin wash so excess water must be removed. This may be done by spinning in a hydro-extractor (commonly called a "hydro") like a giant spin dryer, or by passing through a pair of squeeze rollers.

4.4.5 Trimming and Spreading

These operations are carried out to even up the shape of the skin, remove portions with very different wool types, and to ensure that the skin is well spread to receive the depilatory spray that follows. Trimming is carried out on the moving table that will take the skins under the depilatory spray. The pieces removed are head pieces, brisket pieces, cod-lock pieces and in some plants, shank pieces off the lower leg. In some plants, the head pieces and/or the brisket pieces will have already been removed on the skinning chain or earlier in the fellmongery.

Wool from the trimmings is reclaimed through the ["slipemaster" process].

4.4.6 [Painting]

The skins move from the trimmers through under a [Paint] canopy to receive a spray of the chemical depilatory. Thickened to the consistency of thick porridge and a blue/green colour from the sodium sulphide base, this will work through the skin in the next few hours and dissolve the fibre root allowing easy removal of the wool.

4.4.7 Pairing

As the painted skins come to the end of the moving table (in essence a conveyer belt), a worker lifts them off one by one and in most plants, stacks them on crates (or pallets) alternately paint to paint, wool to wool, to:

(a) prevent the paint from drying out and,

(b) protect the wool as much as possible from paint contamination. In some plants the pairs of skins may be hung over wooden poles or on metal hangers with big sheep skins folded along the back and hung singly.

4.4.8 Storing

Painted skins are held overnight in a cool, damp area known as the "skin cellar" or the "potting shed". They are usually ready for pulling (wool removal) in a few hours but to fit a normal work schedule are held over for pulling the next day.

A skin cellar is desirably cool and draught-free so the skins will not start to dry out and reduce the efficiency of the chemical process.

4.4.9 [Pulling and Grading]

This is the operation of removing the wool from the skins and grading it at the same time. It may be a hand or machine operation, but machines are gradually taking over from hand pulling. In each case the wool off each skin is identified for grade and thrown into a container for that grade. Wool from the edges is graded off as "seconds", while wool that falls on the floor around hand pullers becomes "thirds". As the containers fill, the wool, which is still quite wet, is taken from the pulling area either to the drier, or if it is very short, or contaminated with paint as may be the case with seconds and thirds, to the [Fehrer Wash].

4.4.10 Drying

For this purpose, standard driers as used in wool scours are used. The containers of wool are marshalled according to grade and dried batch at a time. The wool is commonly put through rollers to squeeze out as much water as possible and monitored into the drier through a feed hopper. Wool that has been through the Fehrer wash is treated similarly to wool from the slipe mastered skin pieces.

Drying slipe wool is a complex operation because many of the grades have very different drying characteristics; some dry very quickly and easily while others slowly. An added complication is that there are many small runs and frequent changes with the end of one run and the start of another in the drier at the same time.

From the drier (or driers), the wool is transported to the bins or, in some cases, directly to the press. There are three common means of transport; barrows, conveyor belts or forced air ducts.

4.4.11 Binning

Most plants bin their wool, at least overnight. In order to be sure that all the wool is adequately dried with no wet patches, slipe wool is commonly over-dried to make sure. It is therefore desirable that it be given time to regain atmospheric moisture before pressing so that it can be weighed out and invoiced at a normal regain figure. From the drier, the wool is normally weighed in tared barrows before being taken to the bins.

4.4.12 Pressing

Any of the usual wool presses may be used to produce bales. Only new wool packs are used and bale weights are lower than with greasy wool because, with the higher yield, the same volume of wool weighs less.

4.4.13 Elaboration of Specified [ ] Process

These are covered in the order in which they appear in the earlier text.

4.4.14 Slipemaster Process (for skin pieces)

This is a process which uses the action of scalding temperature water to loosen the wool fibre from the trimmed skin pieces. The operation is as follows:

(i) The pieces are batched according to type, headpieces, briskets etc. and loaded into the feed hopper of the machine. Large ones such as head pieces may be cut into two or three smaller pieces by the operator in order to get a more effective pull.

(ii) A spiked brattice carries the pieces up and into the hot water tank. Here they progress slowly through the scalding water, temperature approaching 100°C.

(iii) On emerging from the water the pieces fall over a lip and into the nip of two fast rollers, one metal and one covered with rubber. Being slippery from the hot water, the skin does not get gripped by the rollers but dances round on top while the wool is pinched and pulled through into the delivery chute. The skin piece meanwhile works along the rollers and drops off the end onto a conveyor which delivers it to the rendering department for boiling down.

(iv) The wool will have picked up some contamination of animal fat in the hot water and for this reason is usually given a cold water rinse and spun in a hydro before being taken to the drier.

Slipemaster wool has a distinctive smell picked up in the hot water treatment because of the fat released from the skin. With good processing control this is no problem.

Another feature is the contamination by small or tiny fragments of skin. It is accepted that slipemaster wools will contain these but if the machine settings and temperature are not right they can be quite big (say thumbnail size) and when dried, are very hard.

All head piece wool is kempy and that of black faced breeds will have black kemp necessitating a specific sub grade for black fibre head pieces. Slipemaster shank wool will be loaded with coarse, short hair fibre while brisket wool is usually the poorest colour of all the grades.

4.4.15 The "Paint"

The active agent of the paint is sodium sulphide. This is dissolved in water to make a solution of the required strength and then thickened with hydrated lime to a slurry, thick enough to stay on the skin instead of running off. The lime also helps maintain the alkalinity of the mix as the chemical is taken up by the skin. For the chemically minded, the components are:

1. Sodium sulphide - Na2S

2. Water - H2O

3. Hydrated lime - Ca(OH)2 - and the mixing is in two steps:

Step 1 2Na2S + 2H2O = 2Na SH + 2NaOH

In this step we have the sodium sulphide combining with the water to form sodium hydrosulphide and caustic soda.

Step 2 2NaSH + Ca(OH)2 = Ca(SH)2 + 2NaOH

This step forms calcium hydrosulphide and more caustic soda and constitutes the paint ready for use.

In practice, the sodium sulphide comes as a hard, crystaline substance in metal drums which are opened as required and hoisted upside-down over a tank of water. A pump circulates the water and plays a jet onto the sulphide, slowly dissolving it. The operator knows fairly closely how much chemical to use but having made up the base solution, tests it with an hydrometer, an instrument which measures the relative density of the solution. The particular instrument used here is the "Twaddel" hydrometer and the measurements are in "degrees Twaddel". The principle of the hydrometer is that the lead shot in the bottom causes it to float upright in whatever fluid is being measured. It will float higher or lower according to the density of the fluid and the reading is taken from the graduated scale. Pure water gives a reading of zero and as sulphide is dissolved into it, the hydrometer floats higher and the reading rises. Paint strengths may be varied according to the age of the animals and the wool length.

Older animals and those with short wool have thicker skins and require stronger paint. The strength ranges from 14 to 25 degrees Twaddel.

Once the solution is at the correct strength, the next stage is the addition of the hydrated lime to give the final chemical composition and to thicken the paint so it will stay on the skins. Lime starts as limestone, calcium carbonate - CaCo3 and is first burnt forming calcium carbide - CaCo. This is allowed to take up atmospheric moisture and becomes calcium hydroxide - CaOH2. In this form it is bagged as a ground powder and distributed to users. In the making up of depilatory paint, it is tipped down a chute into the mixing tank where the solution is stirred with a power stirrer. Based on experience an initial amount is put in, and then the final fine-tuning of the thickness done with the aid of another hydrometer more suited to the heavy suspension we now have. This is the Baume hydrometer.

The final product is kept in circular holding tanks with periodic stirring until required at which time it is pumped to the tank at the paint table.

4.4.16 Painting

From a tank by the paint table, the paint is jetted onto the flesh side of the skins as they pass underneath. In most cases, the jet is designed to give a heavier application to the centre of the skins than to the flanks as the skin is thicker along the back. The jet covers the full width of the table which is in fact, an endless conveyor so all skins get a plastering as also does any wool protruding from under the skins. When the painted skins have emerged, they are taken off the belt have surplus paint recovered from them and are washed ready to receive more fresh skins. The paint is highly caustic and for this reason the workers must wear rubber gloves and protective clothing. Also, an emergency water spray is always adjacent to the paint table.

When paint falls on wool, it dissolves the fibre until it dries or exhausts its chemical action. This results in chunks of material colloquially called "lime" but which in fact are an insoluble compound formed when the chemicals of the paint and the dissolved fibre dry out. One way to remedy this is to wash the wool while still wet as is commonly done with the "seconds", the wool from the edges of the skin which received some spray of paint. However, it is not practicable to wash all types before drying so scourers provide a second option; the use of a "cyclic" opener in the pre-scour treatment. This machine holds the wool in and beats it for a predetermined time to pulverise the contaminate and allow it to fall or wash out as dust.

4.4.17 Alternative Paint Mixtures

There has long been concern to develop alternatives, especially to the use of lime, as the presence of residues in the wool creates sales resistance and makes it difficult to open up new markets. Various other thickeners have been experimented with, flour, potato starch and some based on the cellulosic wall-paper pastes, the latter seeming to have the best potential and some are in commercial use in some fellmongeries. These still require some lime (15-20 % of the normal quantity) to achieve the right chemical makeup and to help maintain a sufficiently alkaline state right through the process.

Another alternative uses caustic soda (Na(OH)2), as the active ingredient, and a propriety cellulosic thickener as a "quick-pull" paint allowing pulling on the same day. This can be used as a strategic option eg. to finish everything on a Friday and give a clear weekend.

4.4.18 A Non-Paint Alternative

Band-knife shearing is being developed as an alternative to the whole existing process. This would entail the skin lying flat and even on a conveyor or drum that would take it under a self-sharpening band-knife operating one to two millimetres above the skin surface. This has advantages and difficulties.

      Advantages:

      - No mess, no contamination, easier sales promotion.

      - Straight through, same day processing.

      - Less danger to less people.

      Problems:

      - Loss of one to two millimetres of fibre.

      - Band knife shearing would present a need to pre-flesh the skins ie. remove any flesh or fat left on by the butchers, in order that
        the skin will lie flat for shearing and that the valuable grain surface would not be ruined.

      - It would not obviate the use of sodium sulphide and lime; these would still be needed to completely de-wool the pelts in pelt
        processing.

4.4.19 Pulling and Grading

"Pulling" is the term given the operation of removing the wool from the painted skin. The pullers grade the wool at the same time. There are two methods in current use, hand pulling and the more recently developed machine pulling.

The hand puller has the painted skins brought up to him on their crates, poles or hangers, and one by one throws them over his "puller's beam" to work on them. The beam is a steeply sloping bench waist high and sloping down and away from him and flanked to each side and in front with small bins or other containers for the wool.

The puller does half the skin at a time starting with the rear end. The puller will remove the britch wool first, throwing it into its container and then run his gloved hands down the sides of the skin, taking off the seconds and depositing them in the appropriate container for their grade. Next is the main body wool which may take two sweeps of the hands to clear. Most of the body wool goes to one of three basic fineness grades with possible three length grades within each. Sometimes the wool must go into a fault grade for vegetable fault, dusty or stain.

Once the butt end is completed, the skin is lifted off and redeposited to work on the front end. The seconds are taken off first and then body wool. Should there be any brands or raddle marks, the affected wool is removed as a "brand" grade.

Frequently there is difficulty with the neck area; folds or bits of fat adhering to skin have stopped the penetration of the paint and the wool will not full freely. A common option here is to take up a pair of hand shears and shear the offending portion. This falls on the floor and along with any other wool off the floor round the puller, is periodically gathered up as "thirds".

The skin, now cleared of most or almost all its wool, becomes known as a "slat" and is dispatched to the [pelt-house] for processing to the pickled pelt stage while the wool is moved on to the Fehrer wash and/or the drier.

4.4.20 Machine Pulling

This is very different. This skins are hung over flat boards, wool side out and are carried up between a pair of beaters which beat the wool off. If fed properly and adjusted properly, these machines are very effective. If not, they can be wasteful of wool and damaging to the skin. Where the skin folds over the top edge of the board the wool needs to be pulled off by hand as the beaters don't have access to it, while if placing is careless with folds in the skin, wool can be left on and/or strips torn off the flanks of skins.

The pulled wool falls onto a moving conveyor which serves as a grading table. It moves up, then flattens out at waist height. A worker each side takes off the seconds while another stationed at the end grades the body wool to the skips (movable bins on wheels) which surround the end of the conveyor.

With machine pulling it is unusual for a britch grade to be considered and commonly the seconds are left ungraded for fineness.

Compared to hand pulling, the machine has its advantages and disadvantages.

         Advantages:

         - It does not tire; it pulls as effectively at the end of the day as it did at the beginning.

         - If properly adjusted and fed, it recovers more wool than hand pulling.

         - In the event of a walk-out or strike, management can clear a backlog of painted skins, albeit without grading the wool.

         - It does not require the extreme physical effort and skill.

         Disadvantages:

         - It does not lend itself to as thorough grading as hand pulling does.

         - There tends to be more paint contamination in the body grades.

         - Damage can be done to the skin, and skin pieces contaminate the wool.

         - It presents a temptation to shortcut methods with even more contamination with paint and skin pieces.

4.4.21 Pie Wool (Sweating)

Prior to the development of the slipemaster machine, wool from skin trimmings was reclaimed by "pieing". In this process, the wet skin pieces were stacked in a neat heap, the "pie", and left to heat and ferment for several days. The wool was then pulled off by hand, the task known as "pie-picking". It was an unsavoury task, the strong smell of fermenting skin permeating the pickers' skin.

During the process, fat is released from the skin pieces and permeates the wool. Beyond a certain percentage, it allows the wool to sustain fire should it heat and ignite spontaneously, hence the fat content and heat testing provisions prior to shipping. Pieing is rare or non-existent today. It would be done only to special request or if the slipemaster machines were broken down and the company didn't wish to dump its trimmings. A very similar process for de-woolling skins, is however, big business in Mazemet, France, the worlds major centre for sweated wools. The woolly pelts from slaughtered sheep are piled up and allowed to sweat for several days after which the wool is pulled off the pelt, sorted, pressed and marketed as Mazemet wool. This method of recovering wool is mainly used when the skin has little or no leather making potential.

4.4.22 Grading

Slipe wools are divided into five basic sections with the necessary range of grades in each.

These sections are:

(1) Woolly Lambs

      This is for wool from lambs that have never been shorn. This wool is regarded as the elite of slipe wool and consequently has
      greatest range of grades in the system. Grading is to fineness length and fault only.

(2) Shorn Lambs

     Body wool from lambs that have been previously shorn. Because of the varying times between shearing and slaughter, length
     becomes a factor so a series of length grades are superimposed over the fineness grades. Oddments and fault grades are often
     combined with adult "sheep" grades to create more marketable quantities.

(3) Sheep

     This category follows the same pattern as the shorn lamb grades except for the addition of a cott grade and a grade for extra long
     wool.

(4) Sheep and Shorn Lamb Combined

     A category designed to take many of the oddment and faulty wools from categories 2 and 3. In this section of grades, fineness is
     not considered; length becomes the deciding factor where two grades of a type are provided, eg. the "stained" grades. However,
     many producers and traders prefer sheep and shorn lamb wools separated.

(5) Sundry Grades

     Grades for wools where no breakdown on age, fineness or, in most cases, length is warranted. These grades include black, dags,
     seedy slipemasters, slipemaster shank wool, sweepings.

Some preliminary sorting of skins is usual so that a group of handpullers or a machine are pulling only one category of skins at a time. Grading for fineness is achieved by recognition of a limited range of fineness-cum-breed types nominated in fellmongery terms as:

                           "Quarterbred"             -          58 and finer,

                           "Halfbred"                  -          56/58,

                           "Threequarterbred"     -          50/56 and

                           "Crossbred"               -           46/50 and coarser.

It is only with woolly lambs that a grade for Quarterbred is provided and likewise, only with woolly lambs is there a grade for particularly coarse wool, this described as "Crossbred - coarse - 44/48 and coarser". Whether or not a plant can make either or both of these grades depends very much on the breeds used in the regions they service.

The maintenance of grading standards is the responsibility of the fellmonger and his supervisors.

4.4.23 Fehrer Wash

This is an enclosed machine which the wool is propelled through by heavy, high speed beaters in the presence of a large volume of cold water delivered through outlets above the beaters. This effectively breaks up the staples of the wool and disperses any clumpiness and paint residues. It is used mainly for contaminated grades such as seconds and thirds and for very short grades which are very difficult to dry otherwise

All grades under 25mm are washed but opinions vary on the wisdom of washing the next length grade up, 25-50mm, some washing the coarser of these and others firmly against it.

4.4.24 Pelt House Procedure

Pulled skins, now knows as "slats" are moved from the fellmongery to the pelt house to be cleaned up and pickled for sale. There are several stages in this process:

1. Liming

This process is aimed at ridding the slats of the very last vestige of wool which it dissolves away with sodium sulphide and lime. The paint on the slats supplies most of the chemical requirement which is re-activated when the slats are loaded into a container with water.

The container may be a large half cylinder vat or steel, fibreglass lined vessel which have wooden paddles to circulate the contents.

With this system, the slats must be physically lifted from vat to vat for each ensuing process.

The slats are paddled round for about half an hour to completely mix the chemical and water which is then tested for strength. Normally, more sodium sulphide will be required to bring it up to strength. The required amount is added and the mix paddled again. After thorough mixing it is let stand with periodic paddling over several hours by which time the wool residues are gone.

2. Deliming

Once the wool is dissolved, the slats are then delimed to remove all traces of the lime and sulphide. This is simply a thorough wash and rinse with clean, cold water. Neutralising follows, using one of a choice of acids to offset the alkaline build-up during the earlier processes. This is important because the later pickling depends on achieving a controlled acidic state.

3. Bating

This is a process which affects the fibre structure of the slat and helps avoid a grain surface defect known as "Mottle", and also cleanses the grain of detritus loosened in the previous processes so as to produce a smooth, silky surface.

Bating is an enzyme process with enzymes obtained from pancreas glands as the active agent.

The slats now are clean, white and silky to touch.

4. Pickling

This involves a soak in a pickle solution of common salt and sulphuric acid. The acid at 1.5% content is the main pickling (preserving) agent while the salt helps and also inhibits undue swelling of the skin. Also added to the pickle will be one of a choice of fungicides to prevent mould developing as the acid and salt alone will not prevent this.

5. Draining

From the pickle bath the now "pickled pelts" are lifted and allowed to drain of surplus pickle, often on barrows from which they will be graded.

6. Grading

Pelts are graded to size and degree of fault. Faults may be inherent in the breed type, be acquired on the farm or caused in the plant.

Inherent:

-   Pinhole - a fault of many fine wool skins whereby whole follicle groups are taken out by the depilations process and leave tiny but  
    visible "pinholes".

-   Ribby and Merino grades, the pelts having a wrinkly or ribbed grain surface.

Farm Faults:

-   Scars - Barbed wire, dog-bite, shearing cuts.

-   Inoculation cysts, open or closed.

-   Cattle tick and/or flystrike damage.

-   Sunburn, rape scald or facial eczema damage.

-   Dermatitis - skin lesions.

-   Cockle, pimple-like raised spots.

-   Seed, penetration by barley grass, storks bill or similar.

Plant Faults:

-   Knife score or hole.

-   Strain.

-   Broken grain.

-   Stunner burn.

-   Torn or misshapen pelt.

7. Packing

The graded pelts are folded in sixes and placed in bins where they continue draining. When ready for pressing, they are counted onto a pallet and the whole package put under a slow acting, hydraulic press which presses them down to the required dimensions and presses more surplus pickle liquor out. Removed from the press the package is strapped and shrink-wrapped on the pallet, branded with company name, grade and number and is ready for dispatch. In this form the pelts may be reasonably held for up to two years if need be, before tanning.

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