CHAPTER III

RIB FABRIC GROUP—HOW STITCH IS MADE FOR DIFFERENT CLOTHS

THERE are numerous conflicting expressions or terms used in the knit goods industry, and one of the most common of these is the term “flat goods.” In the older underwear sections, where the circular machine was used exclusively and the flat machine was practically unknown, the term flat goods indicated underwear fabric made tubular in the jersey stitch on circular spring needle machines, as distinguished from tubular rib fabric made on latch needle machines. At present, in the localities where mills are using both the circular and flat straight needle bed machines, it is generally understood that a flat fabric is a fabric of single thickness made on a flat machine, regardless of the stitch, and any fabric made on a circular machine is known as a tubular fabric. If the stitch should be specified it is mentioned separately.

This latter custom appears to me to be the more logical; therefore, when these terms are used hereafter in this work it should be understood that flat fabric means cloth of a single thickness made on a flat machine, or a tubular fabric cut open so it will lie out flat. The “flat goods” of the old time knitters will be called jersey cloth or fabric.

We will now leave the jersey fabrics for a time, as the making of the tuck stitch and plated work in the jersey stitch are more or less complicated and had better be left until we take up fancy stitches and designs on circular latch needle machines. The tuck stitch is never used in the jersey fabrics on flat machines.

Rib Fabrics

A rib fabric is one which has a rib or wale on both sides of the cloth. It has much more stretch or elasticity than cloth of the jersey group; about twice as much, generally speaking. The elasticity of either one, however, may be varied to a marked degree by changing the length of loop drawn.

Rib fabric is peculiarly adapted for such garments or parts of garments as should be close fitting, such as ladies’ undergarments, cuffs for all kinds of knitted garments, tops of half hose, etc. Fig. 24 shows very clearly the course the yarn takes to form this stitch. It would be well to study this drawing in connection with Figs. 2 and 3 and note carefully the different course the yarn takes in order to form a wale on both sides of the fabric. A photographic reproduction of a plain rib fabric showing both sides is given at _a_, _a_, in Fig. 25.

A properly constructed plain 1 and 1 rib fabric, such as is shown in Fig. 24, should be alike on both sides. Very often this is not the case. A little carelessness on the part of the adjuster in not drawing the stitch the same length on both sides will make a difference on the flat machines, while it is impossible to make them the same on an ordinary circular machine on account of the principles of construction of this machine.

Fig. 26 is a view of a flat machine making the rib stitch, looking down from above. It almost fully explains the method of making this stitch to those who have carefully read and understand the principles of making the jersey stitch. In this illustration the carriage is moving from right to left, and both front and back cams are in operation, therefore both front and back needles are working.

It should be noted that the back plate is set so that the needles of that plate come up at a point in the middle of the spaces between the needles of the front plate. The cams, front and back, being made exactly alike and set exactly opposite one another, must push the needles of both plates up at the same time and draw them down at the same time. When we feed the yarn, indicated by the letter _a_ in Fig. 26, down through the guide, _b_, it is drawn into loops from both sides alternately, as shown at _c_, by the opposite sets of needles, thereby making stitches, or ribs, or wales, on both sides of the fabric. This is the plain 1 and 1 rib stitch.

Varieties of Rib

This stitch, by distortion, or by manipulation of the yarns or needles, or by a combination of two or all three of these things, can produce a number of fabrics different both in appearance and feel. To enumerate the principal ones, there are the half cardigan or tuck stitch, also sometimes called royal rib; the full cardigan, and the rack stitch with the rack on one side of the fabric and the double rack which shows the rack on both sides of the fabric. Then there is the zig-zag stitch, which is quite simple to make but is quite a puzzle to those not familiar with it. There is also the cotton back, which is a well known and popular fabric in the sweater trade.

Then there are many varieties of ribs made either in plain or in combination with one or more of the above by taking needles out of the machine at predetermined places, or by the Jacquard system of selecting needles. There is also the system of making designs by the cut pressers and pattern wheels, which is used on circular machines only.

Half Cardigan or Tuck Stitch

The half cardigan or tuck stitch is used more than any other of the ribbed group, though it is generally used in combination with the plain rib. The body and sleeves of the ordinary rib sweater, and much of the rib underwear produced, are made in this stitch while the cuffs are plain rib. The reason for this is that the half cardigan rib will knit up considerably wider, with the same number of needles, than the plain rib, therefore it is possible to make a shaped garment without cutting and sewing up again. Also the plain rib comes out lighter and thinner so makes a more desirable cuff for sweaters and underwear. It also has more life or spring to it, which is another desirable feature.

The half cardigan or tuck stitch is the one that is almost invariably used in making the well known cotton back sweaters. It is believed by many people who are familiar with this fabric that the back stitch of cotton does not come through on the face, but in this they are mistaken. The face stitch does not go through on the back, but the back yarn does go through on the face.

Fig. 27 is a line drawing showing the course the yarn takes in making this stitch and a careful examination of it will demonstrate to the reader that this is the case. The dotted line _e_, _e_, indicates the wale on the face and _f_, _f_, shows the wale on the back. It will be noted that the back stitches of yarn come through to the face of the fabric and connect the preceding and succeeding stitches, _c_, _c_, the same as in the plain rib, but there is this difference, in the plain rib these face stitches are, or should be, just the same length, while in the half cardigan, on account of the back stitch of this course holding over for one course, it necessarily draws a longer stitch in the back and the yarn for this long stitch must come from the face stitch, thereby making this face stitch very short.

In the drawing the stitches are not proportioned just as they lie in the actual fabric, for if they were it would be very difficult to trace their course. In the fabric the stitches _b_, _b_ are so short that they are almost completely covered by the large, full, round stitches, _c_, _c_, _c_. These stitches are full and large from the fact that where they go through to the back they do not form a loop but simply cross over the back loop as at _d_, without being drawn through. These are completely covered by the loops _a_, _a_, in the back wale.

How the Half Cardigan or Tuck Stitch Is Made

The diagram at Fig. 28 shows the method used to make the half cardigan or tuck stitch on a flat machine. The cams shown are what are known as the Lamb system and are called the automatic cardigan or drop locks. The word “locks,” as applied to the flat knitting machine, means a full set of cams attached to the cam plates ready to affix to the carriage. There are a number of different systems of constructing these locks, but the one selected is the most simple of all and for this reason is used for illustration first. The others will be taken up at the proper place.

In Fig. 28 only a part of the needle plates are shown. They are attached to a frame at an angle of 90° to each other and 45° to the horizontal as explained before. The cams are shown in working position with the carriage (to which they are attached when in use) removed. As indicated by the thread _h_, they are being moved toward the far end.

It should be noted that the automatic drop V-cams _a_, _a_, are in different positions. These cams are made so that they swing freely on the pivots _b_, _b_, and the swing is inside of the limits of the positions of the two cams in the drawing. It is controlled by pins on the top side of the swinging ends, the pins coming through a slot of the proper length in the cam plate to stop them at the right place.

When starting to move these locks from the near end toward the far end, the cam _a_, on the left, might be in any position within the limits of the before mentioned slot in the cam plate, but the instant it comes in contact with the butts of the needles it is automatically forced to the position shown.

In making the half cardigan stitch the right hand cam is held up to the top, as shown, at all times by means provided. This position forces the needles high enough so that the latches are above and clear of the loop that is on the needle, therefore when the needles are drawn down again by the cam _f_, they draw new loops and cast the old ones off over the latch and hook, and they drop down on the new loop, just as explained in describing how to make the plain rib. This refers only to the needles in the right plate.

The cam _a_, on the left side, however, having been swung down to its lowest position by contact with the needle butts, raises the needles only about one-half of the normal distance. Or to put it differently, the needles raise high enough to open the latches and catch the yarn when being drawn down again, but not high enough to permit the loop that is on the needle to slide down below the latch. Therefore, after the completion of the course we have the right side with the new loop drawn through the old one as in plain rib, but the left side still retains the old or previous loop and also the new one as at _j_. This leaves two loops on every needle on the left side and one on the right when the course is completed.

On the return course, from the far end to the near end, when the point _i_ of the left cam, _a_, comes in contact with the first needle it must swing up in the same position as the right cam, _a_, therefore all the needles will draw the new loop through the two preceding ones and clear themselves, leaving only one loop on each needle as in the plain rib.

On the next course, from the near end to the far end, the left hand needles again hold the old loop and take on a new one as just explained, while the right hand needles cast off the old ones and hold only the new ones.

To condense the operation into a few words let us say that the left hand needles always must hold the two stitches while moving in one direction, and clear them off and hold only one on the return course; while the right hand needles always cast off the old stitch and hold the new ones only. The right hand needles would make the face side of the fabric.

The writer has made a special effort to explain the formation of this particular stitch, and the reader should make the same effort to get this formation clear in his mind, for this stitch is the base of almost all of the fancy stitches or design work which will be taken up later. The system used in design work is of course entirely different from the one just described, being what might be called a selective system, that is, a method whereby the designer may select the proper needles at the proper time and place to make the tuck stitches block out the design wanted.

Fig. 25, at band _c_, shows the tuck or half cardigan stitch; _b_ is the face and _c_ is the back. If studied carefully the reader will notice that the face side, _b_, has a full round stitch, while _c_, or the back of the fabric, has a small narrow stitch.

The Full Cardigan Stitch

The full cardigan stitch is not nearly so generally used as the half cardigan and plain rib stitches. It is seldom if ever used in making underwear or any fine fabrics. When it is made it is usually used for sweater fabrics or other novelty wearing apparel of this character.

A line drawing of the full cardigan stitch is shown in Fig. 29. This stitch, as its name would indicate, is made in the same way as the half cardigan only the stitches are held alternately on both rows of needles on alternate courses. Referring again to Fig. 28, in making the full cardigan stitch the cams would operate exactly the same while moving toward the far end as shown and explained for the half cardigan. But the means provided to hold the right hand cam, _a_, at the top position would have been removed, so that on the return from the far to the near end this cam would be thrown down to the same position as the left hand cam, _a_, is shown, while this left hand cam would be forced up into the position in which the right hand cam is now shown. In other words, the stitch would be the same with the carriage or cams moving in either direction, only it would alternate on each course from one row of needles to the other.

We will refer back to Fig. 25, which shows both sides of a piece of fabric with the three stitches we have just discussed in one piece. This shows quite plainly the individual characteristics of each. All have the same number of needles or wales, the same yarn was used, on the same machine; yet how different the results!

The most marked difference is in the width. There is proportionately the same difference in the thickness, but this cannot very well be shown. It should be observed that the stitch or loops of the plain rib _a_, _a_, and the full cardigan _d_, _d_, are the same on both sides of the fabric, while the stitches in the half cardigan, _b_ and _c_, are not. It will be noted also that the stitch of the plain rib is much smaller than that of the two cardigans, also that the wales or ribs hug very close together in the plain rib, while they are separated more or less in the cardigans.