can be used a more uniform fabric can be made by increasing the number of different weft lengths until it is no longer cost effective the embodiment shown in fig6 uses one weft insertion device more complex patterns having a single weft yarn of different lengths instead of pairs is shown in fig7 in this embodiment three weft insertion devices are required the length of the weft insertion also referred to as the shot or throw direction in knitting can be controlled with cams pins knuckles or electronically depending on the style and age of the knitting machine used the level of control generally available in all machines of this type is such that each weft insertion shot or throw can be tailored to be of different length the combination therefore of variable length weft insertion and conical take up will produce the material intended the helical fabric of the present invention has been said to have a u201c more constant u201d thickness than that of the prior art the thickness of a single layer of fabric is not perfectly uniform or constant but varies by the width of a weft fibers and insertion length fig8 is a graph that shows that the weft volume fraction 124 in the prior art increases from od to id this increases the thickness fig9 shows that the weft volume fraction is more constant from the od to the id and the thickness will.