A knitting needle is really a lever (http://en.wikipedia.org/wiki/Lever) for moving loops of yarn.
A knitting needle's position in space can be described by its pitch, yaw, and roll. (http://en.wikipedia.org/wiki/Aircraft_principal_axes) The needle changes pitch, yaw, and roll by rotation around a center of rotation (or the fulcrum point, when the needle is considered as a lever). Thus, a change in pitch allows both ends of the needle to describe arcs in space while the center of rotation has zero motion vector in space. And a needle can vector in space without changing its pitch, yaw, or roll. When a straight needle rolls, there is no apparent motion, but when a bent needle rolls, one or both ends of the needle describe arcs in space.
Moreover, a knitting needle can flex.
Now:
1) The motions of a hand held held knitting needle are those of a class 1 lever, and limited to pitch and yaw, and the applied leverage is about 1:3.
2) With a knitting stick and short, stiff, straight needles, the motions are still limited to pitch and yaw, but the fulcrum is at the cow band, so it is a class 3 lever with and the applied leverage is in the range of 1:20 to 1:40. This takes a lot of stress off of the hands when knitting tight sock fabrics.
3) With a knitting pouch, long, straight, needles act as class 3 levers, and the traditional needles provide leverage of 1:40. With short needles the leverage is more like 1:20. A common use is to reduce the stress allowing sustained knitting.
4) In gansey knitting, the long needles flex, store energy, and that energy is then returned to the knitting stitch. The effective leverage is very high e.g., (1:50) This allows sustained knitting of very tight fabrics.
5) Swaving is different because the needle rolls. In swaving, one leg of the working stitch acts as one fulcrum, the knitting sheath acts as another fulcrum to produce a compound lever as the needle rolls. (http://en.wikipedia.org/wiki/Compound_lever).The effective leverage is very high e.g., ( more than 1:50) This allows sustained knitting of very tight/ fine fabrics.
6) In the various methods of knitting that use hooks, the needles vector, and there is essentially no useful leverage. The motion is driven by the large muscles of the shoulders and upper arms, so it is a powerful motion that can produce very tight fabrics, but no mechanical advantage is gained.
Thus, in fact, there are 6 different hand knitting motions that competent knitters understand. Each knitting motion has virtues and vices, which need to be understood. Knitting sticks, knitting pouches, and knitting sheaths provide additional leverage for knitting fabrics that cannot be reasonably knit with hand held needles by even the strongest and most expert knitters. Anyone that thinks that knitting with 1:3 leverage can produce all the fabrics that knitting with 1:50 leverage can produce, simply does not understand the basic physics of their craft.
A knitting needle's position in space can be described by its pitch, yaw, and roll. (http://en.wikipedia.org/wiki/Aircraft_principal_axes) The needle changes pitch, yaw, and roll by rotation around a center of rotation (or the fulcrum point, when the needle is considered as a lever). Thus, a change in pitch allows both ends of the needle to describe arcs in space while the center of rotation has zero motion vector in space. And a needle can vector in space without changing its pitch, yaw, or roll. When a straight needle rolls, there is no apparent motion, but when a bent needle rolls, one or both ends of the needle describe arcs in space.
Moreover, a knitting needle can flex.
Now:
1) The motions of a hand held held knitting needle are those of a class 1 lever, and limited to pitch and yaw, and the applied leverage is about 1:3.
2) With a knitting stick and short, stiff, straight needles, the motions are still limited to pitch and yaw, but the fulcrum is at the cow band, so it is a class 3 lever with and the applied leverage is in the range of 1:20 to 1:40. This takes a lot of stress off of the hands when knitting tight sock fabrics.
3) With a knitting pouch, long, straight, needles act as class 3 levers, and the traditional needles provide leverage of 1:40. With short needles the leverage is more like 1:20. A common use is to reduce the stress allowing sustained knitting.
4) In gansey knitting, the long needles flex, store energy, and that energy is then returned to the knitting stitch. The effective leverage is very high e.g., (1:50) This allows sustained knitting of very tight fabrics.
5) Swaving is different because the needle rolls. In swaving, one leg of the working stitch acts as one fulcrum, the knitting sheath acts as another fulcrum to produce a compound lever as the needle rolls. (http://en.wikipedia.org/wiki/Compound_lever).The effective leverage is very high e.g., ( more than 1:50) This allows sustained knitting of very tight/ fine fabrics.
6) In the various methods of knitting that use hooks, the needles vector, and there is essentially no useful leverage. The motion is driven by the large muscles of the shoulders and upper arms, so it is a powerful motion that can produce very tight fabrics, but no mechanical advantage is gained.
Thus, in fact, there are 6 different hand knitting motions that competent knitters understand. Each knitting motion has virtues and vices, which need to be understood. Knitting sticks, knitting pouches, and knitting sheaths provide additional leverage for knitting fabrics that cannot be reasonably knit with hand held needles by even the strongest and most expert knitters. Anyone that thinks that knitting with 1:3 leverage can produce all the fabrics that knitting with 1:50 leverage can produce, simply does not understand the basic physics of their craft.
When the Victorian Ladies of fashion established knitting as a leisure pastime (as distinct from a professional craft) they set the social conventions of the pastime. Every pastime from cricket to horse racing and grouse hunting has social conventions. One of the social conventions of knitting as a pastime was that both needles must be hand held. This did away with professional knitting techniques All modern knitting needles from Faberge to Signature to the various cable needles, all have the same leverage. Long (gansey) needles, used as hand held needles still have the same leverage, and provide no advantage. Any knitter that used a knitting sheath or knitting stick was not considered a person of fashion. If you wanted to use a knitting pouch or knitting sheath, you had to do it behind the closed doors of a commercial establishment or live someplace like Shetland.
This social convention limited the leverage available to the leisure knitter. It provided a level playing field, the difference in quality between any two samples of knitting was the skill of the knitter, and a knitter could not use different tools to knit better. This social convention took knitting technology off the table. The mind set that knitting technology does not matter persists.
0 comments:
Post a Comment