It depends on your project. You need the size needle that will give you the stitch width and stitch length called for in the pattern. The pattern calls for a specific gauge, so you'll need to try out different needles, knitting a swatch on each needle size, and counting the number of stitches across and down to match the pattern specification. Does the pattern not give you a needle size? Needles come in either straight or circular in all various sizes as long as you stay within the same brand needle. (Needle brands differ from one to another, so try to stay within only one brand.) So a straight needle size 6 should be the same size as a circular needle size 6 (of the same brand).
However, although it may call for a specific size needle, you will still need to knit some test swatches because knitters usually knit looser or tighter, so one needs to adjust the needle size to accommodate those differences, ie someone who knits tightly may get 8 stitches to an inch, but a loose knitter may get only 6 stitches. But if the pattern says to cast on 48 stitches in for row 1, that means the 8 stitch gauge will yield a project that measures 6 inches wide (48/8=6). But a 6 stitch gauge will yield a project of 8 inches wide (48/6=8). The result would be one project will be 2 inches wider than the other.
But that is only half of the problem as you would still need to measure the number of rows per inch to get the length of the project. If there are more rows to the inch than specified, a garment with say an armhole that may be too small. If there are fewer rows to an inch, the result may be an armhole that is way to big.
Be very careful with your pattern and yarn selection. You will be much more successful if you stick to the
number ply and yarn weight specified in the pattern, ie if the pattern calls for 2-ply 2 oz yarn, there may be some particularly difficult issues with substituting a 4-ply 4 oz. yarn. You may end up with a project that will not fit. For instance, you wouldn't want to use a heavier yarn to knit a baby garment. Baby garments usually call for baby yarn which is a specific ply and weight.
How to Measure Your Gauge in Knitting
earthguild com
How to Measure Your Gauge in Knitting
3 Things You Might Not Know About Knitting Gauge Adjustment
knitting stitch abbreviations
×