Theory of Silk Weaving | Page 8

less uneven, it is safer to count the cocoon fibers of several threads and to take average thereof.
It requires the experience of years to judge with any degree of certainty as to the origin and quality of silk, whether it be "classical," "extra," "sublime," etc.
There are machines wherewith to ascertain exactly the twist, that is, the number of turns the silk has received in the throwing process.
In the dyeing we distinguish two great classes, of which the names themselves give a good definition. "Bright" has a brilliant luster, while "souple" has more of a dull, subdued appearance. To find out whether the silk has been weighted in the dyeing process, we may compare it with other silk of which the exact conditions are known, or we may burn a small quantity of it. Unweighted silk does not burn readily and leaves a residue of white ashes, while heavy weighted silk burns lively, leaving black, charry ashes.
[Page 70] 4. REED CALCULATION
We count the number of repeats of the weave in a given space, generally ? or ? inch, and multiply this with the number of threads one repeat contains, which gives us the reduction of the warp.
Suppose we had a taffeta, which, as we know, has only 2 ends to a repeat, and counted 30 interlacings per ? inch on one pick; we would have 60 threads per ? inch or 240 per one inch. In this case the reed may be 80 by 3 or 60 by 4.
Another instance: In an 8-shaft satin we count 10 warp-threads, which bind on the same pick in ? inch; this, multiplied by 8, equals 80 ends per ?, or 320 per one inch; the reed will be an 80 with 4 in a dent or a 64 by 5.
In short, the number of the reed is found by dividing the number of warp-threads that are to go in one dent, in the number of ends per inch. Sometimes, the reed marks are clearly visible in a sample by holding the latter against the light. Silk fabrics move with very few exceptions within the limits of 50 and 90 dents per inch.
To learn the full number of dents required for the width of the cloth, simply multiply the dents per one inch with the width, adding a certain allowance for shrinkage. The edges, of course, must also be taken in consideration, and very often the dents that are taken up by the latter are used to counter-balance that shrinkage.
5. DRAWING-IN THE WARP IN HARNESS AND REED
Here we must specify the number of dents that contain the same number of ends, and whether the latter are single or double, also the number of shafts and the method of drawing-in.
[Page 71] 6. WARPING TICKET
To make out the warping ticket, we need to ascertain the total number of ends, whether leased single or double, and the arrangement of the colors.
7. HARNESS ARRANGEMENT
This is governed by the number of ends to be drawn in and the necessary shafts. If we have, for instance, 100 threads per inch to be drawn on 4 shafts, we must give each shaft 25 heddles per inch. There are generally between 25 and 45 heddles per inch on one shaft.
8. REDUCTION OF THE FILLING
Here we state the number of picks per inch, give directions as to doubling, if such is necessary, and if more than one color or shuttle is used, the rotation thereof.
9. CALCULATION OF WARP AND FILLING
The system adopted in this country for specifying the size of silk is based on the weight in drams (avoirdupois) of a skein containing 1000 yards. A skein, thus weighing 5 drams, is technically called 5-dram silk. The number of yards of 1-dram silk to a pound must accordingly be 256000. The formulas for figuring the amount of silk required for a piece of cloth are as follows:
Warp Calculation
_Multiply_: Number of ends��length��count ----------------------------- _Divide by_: 1000 yards��256 drams
[Page 72] Filling Calculation
_Multiply:_ Picks��xply��width��length of piece��count -------------------------------------- = lbs. _Divide by:_ 1000 yards��256 drams
The result in both cases will be in pounds.
The system of grading the silk which is in vogue in Europe, and which is employed by a number of mills on this side, is as follows:
1 skein of 500 meters, weighing 0,05 grams = 1 denier international or 1 " 476 " " 0,053 " = 1 " Turin system or 1 " 476 " " 0,051 " = 1 " Milan "
The warp calculation, taking the international denier, would run:
ends in warp��length��denier��0,05 gram -------------------------------------- _divided by:_ 500 meters
for the filling: Picks per meter��xply��width��denier��0,05 gram --------------------------------------------- _divided by:_ 500 meters
Result in metric weight, kilograms and grams.
10. FINISHING
Give directions as to the process of finishing to which the goods are to be subjected, whether to be pressed, calendered, sized, moir��d, etc.
11. CALCULATION OF COST
If all the