THE numbers of cotton yarns are based upon the hank of 840 yards, the number of hanks in 1 lb. being the “counts.”
It follows that if 840—the yards in one hank—be multiplied by the counts, the result will be the yards in 1 lb. of that count.
Thus in 1 lb. of 30’s yarn there will be 840 × 30 = 25,200 yards, and the yards in a pound of any count may be found in the same manner.
The counts of worsted yarns are based upon a hank of 560 yards, and the number of hanks in 1 lb. Avoirdupois is the count of the yarn.
Linen yarns are based on a hank or lea of 300 yards, and the number of these in 1 lb. is the count of the yarn.
Spun silk, which is the silk chiefly used in cotton fabrics for stripes and headings, is numbered on the same system as cotton yarns. The number of hanks of 840 yards in 1 lb. is the count of the yarn.
Net silks or thrown silks are numbered on an altogether different system. The “skein” or hank is 520 yards, and the number of deniers—533⅓ deniers = 1 oz.—which a skein weighs indicates the number of the yarn. In silk manufacture the number of the yarn is called the “size,” the word “count” being used to denote the closeness of the reed.
Another system is used for silk yarns called the Manchester scale. This is based upon the hank of 1,000 yards.
The number of drams which one such hank weighs is the “size” or number of the yarn or thread.
In the former scale the yards per ounce may be found by multiplying the yards in a hank by the deniers in one ounce, and dividing by the number of deniers which a hank weighs.
The yards in an ounce of 40 denier silk will be—
In the Manchester silk scale the yards per ounce of a 4 dram silk may be found by multiplying 1,000, the yards in a hank, by 16, the drams in an ounce, and dividing by the number of drams which the hank weighs, viz. 4; thus—
1000 × 164 = 4000 yards per oz.
Twofold Yarns in cotton, worsted, and linen are numbered according to the count of the single yarn, with the number of folds put before it. Thus a 2-40’s yarn means that the yarn is composed of two threads of 40’s single, making a twofold yarn of 20 hanks to the pound.
In spun silk the yarns are nearly always two or more fold, and the number of the yarn always indicates the number of hanks in 1 lb. The number of folds is usually written after the hanks per pound. Thus, 40’s-2 spun silk indicates that the yarn is 40 hanks to the pound, made up of two threads of 80’s single.
It sometimes occurs in fancy yarns that threads of unequal thickness are twisted together. If a 60’s thread and a 40’s thread are twisted together, the count of the doubled thread will not be the same as if two threads of 50 hanks to the pound, but will be something less than this.
It is obvious that when the two threads are twisted together the weight of a hank of the doubled thread will be 1/60 + 1/40 of a pound, and by adding these fractions together the counts of the twofold yarn may be obtained. Thus—
140 + 160 = 3 + 2120 = 5120 = 24’s counts.
Another method of obtaining the same result is to multiply the two numbers together, and add them together, and divide one result by the other. Thus—
If three or more unequal threads are twisted together the counts of the resulting thread may be found by adding the fractions of a pound which a hank of each count represents.
Example.—Find the counts of a threefold thread composed of one thread each of 10’s, 20’s and 60’s cotton.
110 + 120 + 160 = 6 + 3 +160 = 1060 = 16 or 6’s counts.
Some allowance must be made for the twisting of the threads, but this will vary with the number of turns per inch in the yarn, and so is not taken into account in the example.
If it is required to obtain the weight of each count in 100 lbs. of the threefold yarn, the following is the method.
As one count is to the resulting count, so is the total weight to the weight required of that yarn—
Reeds and Setts.—The system of numbering reeds, now almost universal in the cotton trade, is known as the Stockport or Manchester count. The number of dents or splits per inch in the reed with two ends in each dent is the basis of the system. If the reed has 30 dents per inch, it is called a 60 reed, because if there are two ends in a dent in the 30 dents there will be 60 ends per inch. The number of the reed is always the same as the ends per inch in the reed, if the ends are all two in a dent.
A 60 reed Stockport counts, if reeded three ends in a dent, will have 90 ends per inch, because a 60 reed has 30 dents per inch, and if there are three in a dent, there will be 30 × 3 = 90 ends per inch.
Various other systems have been used, but are gradually giving way to the simpler Stockport or Manchester system. Some of these are—
The Bolton count, in which the number of “beers” of 40 ends, or 20 dents, in 24¼ inches is the basis of the system.
The Blackburn count, in which the number of beers in 45 inches was the basis. The beer, as above, being 20 dents, representing 40 ends in a beer.
The Preston count was based on the number of beers in different widths.
The 6-4 count was based on the number of beers of 20 dents—representing 40 ends—in 58 inches.
The 9-8’s count was based on the number of beers in 44 inches.
The 4-4’s count was based on the beers in 39 inches.
The 7-8’s count was based on the beers in 34 inches.
The Scotch system is based on the number of dents in 37 inches. Thus in a 2000 reed there will be 2000 dents in 37 inches, representing 4000 ends in that space.
The Bradford system is based on the number of beers of 40 ends in 36 inches. If there are 50 times 40 ends in 36 inches, it is a “50 sett.”
To find the number of ends per inch in a given sett, it is necessary to multiply the sett by 40 and divide by 36, thus—
50 sett × 4036 = 552036 ends per inch.
Quantity of Material in a Piece.—To find the weight of warp and weft of given counts in a piece, the total length of yarn in the piece may be found, and divided by the yards in 1 lb. of the counts of yarn used. This will give the weight in pounds. The following example will make the principle quite clear:—
Example.—Find the weight of warp and weft in a piece woven 30 inches wide in a 70 reed (Stockport) cloth 90 yards long, from 95 yards of warp, 80 picks per inch, the counts of twist or warp being 30’s, and counts of weft 40’s.
If the piece is 90 yards long, the length of warp used will be somewhat in excess of this, as the warp in interlacing with the weft is bent out of a straight line. The amount of “milling up,” as it is called, varies according to the number of intersections in the pattern or weave of the cloth, and with the counts of yarn used. It will also vary considerably according to the elasticity of the yarn. Twofold yarns are more elastic than single, and therefore will require a shorter length of yarn for a given length of cloth.
In this example 95 yards of warp are used to weave a 90-yards piece, an allowance of a little over 5 per cent.
In making the calculation for the weft it is necessary to take the width in the reed, as this length of weft is used every pick. The cloth will contract a little owing to the pull of the threads when woven, and when calculating for a given width of cloth care must be taken to calculate for the reed width and not the cloth width only.
In the present example the width in the reed is given, and so the cloth will be somewhat narrower than this when woven.
TO FIND WEIGHT OF WARP.
TO FIND WEIGHT OF WEFT.
Therefore, weight of weft = 21600033600 = 6 lbs. 66⁄7 oz.
Weight of weft = 6 lbs. 66⁄7 oz.
Weight of warp = 7 lbs. 14⅔ oz.
In the weft calculation, the picks per inch multiplied by the width in the reed in inches gives the inches of weft in one inch of cloth. This multiplied by 36 will give the inches of weft in one yard of cloth, and divided by 36, this gives the yards of weft in one yard of cloth. The two 36’s may be left out, as it is obvious that the yards of weft in a yard of cloth are the same as the inches of weft in an inch of cloth. The formula to calculate the weight of warp in a piece is as follows:—
Inches
in reed × length of warp in yards × ends per inch in reed840 × counts
= weight of warp.
The formula for the weft is—
Inches
in reed × length of piece in yards × picks per inch840 × counts
= weight of weft.
Working out the previous calculation in this manner, we get—
30 × 95 × 70840 × 30 = 7 lbs. 14⅔ oz. of warp.
30 × 90 × 80840 × 40 = 6 lbs. 66⁄7 oz. of weft.
If it is required to find the number of hanks, it is only necessary to leave out the counts in the above formulæ. Thus we get—
Inches wide × length × ends per inch840 = hanks,
and using the figures in the previous example—
30 × 95 × 70840 = 237½ hanks of warp.
Before the actual cost of a piece of cloth can be calculated, it is necessary to know the price to be paid the weaver. In Lancashire the payment is made according to the list agreed upon by both employers and employed. For plain cloths and twills a new uniform list has been agreed upon, and this is now generally accepted. The following is the new list:—