Your answer depends on the yarn weight you're working with. You'll need a longer needle for bulky weight yarn than you will need for lace weight.
yup. the bigger the needle, the bigger your stitches. likewise, the smaller your needle, the smaller your stitches. simple really.
I had a look and the 16 Addi Turbo does seem to be a circular needle. The Australian equivalent would be a 40cm 6.00mm circular needle.
Note: round needles are almost always called circular knitting needles. In some cases, circular needles will work just as well as double pointed needles. But more often than not, only double pointed needles will work. Why? With double pointed needles, one can knit with as few stitches as they want. This makes them ideal for knitting the tops of hats, which are decreased to a very few number of stitches, and other items where few stitches are knitted. However, if one is knitting with a large number of stitches, then circular needles will work fine, maybe even better, but circular needles have a "minimum stitch limit." Thus, they only work if the pattern works with lots of stitches. So in order to figure out whether circular knitting needles will work for your pattern, read through the instructions, and determine the point at which there will be the least number of stitches on the double pointed needles. Try to estimate the lowest number of stitches that will work comfortably on the circular needles, and decide if the stitches in the pattern will fit on the circular needles.
I think your question is: if you knitted 30 stitches, how long, in inches, would that be? There is no way to tell. Different types of yarn (wool, cotton, silk, rayon), stitch up differently. The size of the yarn--fingering, worsted, bulky--would change the length that 30 knit stitches would make. Also the size of the needle would change how long 30 stitches would be. If you really want to know, knit a swatch of 30 stitches, and measure it yourself. That is the only way to know for sure.
1.5 for needle length to be used in the deltoid.
I would say to first check what the label on the yarn ays for your project. However I know sometimes that isnt possible, so you have to make do. I would start with a size 5 knitting needles. First make a gauge swatch I knit about 20 stitches and about 15 to 20 rows, the measure how many stitches per inch I have. Depending on if your a tight or loose knitter you might have to go up or down a size or two. In general the smaller a needle is the more stitches per inch you can make, the larger a needle is the less stitches.
21 gauge
The number of stitches you need per inch depends on the type of fabric you are sewing. The weight, thickness and type of fabric sewn will determine the stitch length you use. In a quilt, you will have fewer stitches, such a six or eight per inch. For a seam on clothing, a medium weight fabric will use 10 - 12 stitches, for heavier fabrics, 8 -10 will work better. In knitting and crochet, the stitches per inch are determined by the size of your needles, the tension you use when working the stitches, and the weight of the yarn or thread. The pattern you use will specify the stitches and needles you need, called the gauge.
I think the needle size and yarn weight are more important than the stitch type. Different sizes of either dramatically change how the stitches look, how they lay down.
if your talking about needles than you just knit with a bigger size needle. if you're talking about making it bigger than you just have to add on a bunch of stitches to see if it fits.
The metric unit of length typically used to measure the eye of a needle is millimeters or micrometers due to the small size of the opening.
The size of a needle is typically expressed by its gauge, which is a numerical scale where a higher number indicates a thinner needle. For example, a 30-gauge needle is finer than an 18-gauge needle. Additionally, needle sizes may also be described by their length and type (e.g., hollow bore, straight, or curved) depending on their intended use in medical procedures or sewing.