Tuesday, January 12, 2010

Uneven knitting, part 2: bunching, big stitches and lumpy fabric--the problems of too-long runs

Part 1 of this series talked about uneven fabric due to  "rowing out,"  which is fabric uneven from row to row. In this post, we have the related problem of knitting which is uneven from column to column. Sometimes, this problem is easy to identify, expressing itself in bunchy vertical columns across the face of the fabric, per photo below. Sometimes, however, this problem expresses itself mysteriously: just a few enlarged stitches across an otherwise perfect row.
Unevenness is unavoidable when you first start knitting. But some knitters remain plagued with this issue. In my experience, this mainly results from a positioning problem called "too-long runs."
To explain: In knitting, we have two needles--the holding needle and the working needle. (For most knitters, the left is the holding, the right the working, but for mirror image knitters, this is reversed.) To knit a new stitch, three things have to happen, and two of them concern positioning.
  • The stitch about to be knit has to be pushed or drawn away from its neighbors, onto the tip of the left (holding) needle--positioning issue #1
  • The stitch has to be knit
  • The newly-made stitch has to be parked on the right (working needle) far enough out of the way to permit the next stitch to be made without falling off in its turn--positioning issue #2.
For smooth knitting, each of these things ought to happen the same way each time. Stitches about to be made should be drawn forward from the waiting pack by the same distance, new loops drawn through ought to be the same size, and each new-made stitch ought to be parked out of the way by the same distance from the working-needle tip.

The problem of the middle stage--drawing the same amount of yarn through each time to make consistent loops--is dealt with in this post about gauge: the TLDR is this is a problem of feed tension. For today, we are only looking at the positioning issues of moving the stitches toward being knit, then out of the way afterwards. These are the positioning issues which cause the problem of fabric uneven across the columns. There are two roots of the problem
  1.  In knitting, you're in the odd position of trying to slide stitches around while also holding--clamping, actually--those very same stitches in one place as you grasp the knitting needles to operate them. You're trying to hold and slide at the same time.
  2.  Knitting is complicated: positioning your hands just right is a bit of a chore. 
 The natural tendency is not wanting to shift the hands too often, therefore making as many stitches possible before re-positioning the hands.

I've observed that knitters who create smooth fabric overcame this tendency. They re-position their hands every few stitches, or even, every stitch. But knitters whose fabric is not-so-smooth tend to hang on to the needles, shoving forward a bunch of stitches at a time, knitting all these--perhaps as many as 10 stitches or even more--without repositioning their hands on the needles. In other words, there's no repositioning until it becomes absolutely necessary because no more stitches are reachable on the left needle, while on the right needle, the newly-made stitches are so crammed together, they're about to fall off the needle tip.

In bunchwise knitting, the first stitch to be knit is separated from its left-hand neighbor by very little distance, while the last stitch of the bunch is drawn very far from its neighbor--a neighbor being held back to be the first stitch of the next bunch. Similarly, the first stitch of the bunch to climb aboard the right-hand needle is held a fair distance away from its right-hand neighbor--the last stitch of the old bunch--while the last stitch to climb aboard is jammed and crammed up against the other stitches newly-made in the same bunch.
The evil is that the running yarn--the yarn coming from the skein--has to run a further distance between stitches in widely-separated bunches than between stitches of the same bunch.

If this is a one-time random event--maybe trying to get in a few last stitches before running for a delivery at the door--the result is the mysterious set of too-big stitches in the middle of an otherwise good row. This sort of problem can usually be blocked out: as the knitting flexes, the small amount of excess yarn stretches from one place to another.

However, when the distortion is systemic, the fabric can't recover. If the hand routinely bunches up roughly equal numbers of stitches, the fabric soon begins to distort into vaguely vertical columns, each column representing the width of the bunch-wise knitting. Fabric knit bunch-wise, where uneven amounts of yarn routinely lays between stitches in adjoining columns, is unlikely to ever lay smooth, not even when properly blocked.
One reason why the old-time production hand-knitters used knitting sheathes or belts to hold the needles was to separate the holding function from the knitting function. If the needles and fabric can be supported without the hand clamping the stitches to the needle, the hand becomes free to guide the stitches, smoothly and evenly sliding each stitch to the working tip, then taking it away again, always moving the stitches by the same amount. 
 In machine knitting, this problem of uneven runs has been solved by having an entire bank of needles, one for each column. These needles are in fixed position, so the running yarn always travels an identical distance between adjoining stitches.
For the modern hand knitter, the cure is to reposition the hands and the stitches often, keeping the runs short--a few stitches, at most. Slower initially, yet soon the hands take the situation in stride. Keeping runs short by moving the stitches evenly up to the left tip and away from the right becomes one more automatic gesture among many made by the knitter's hand, a smoother fabric resulting.

You have been reading TECHknitting blog on "uneven knitting--bunching, big stitches and lumpy fabric."