Here is an interesting picture (well it is at least for me lol) of three small gauge swatches each 20 stitches wide and 21 rows tall. The top two were knit on the same size 5 needle, the bottom swatch was knit on a size 3.
Garter stitch fabric has more rows per inch than stocking stitch fabric but what surprised me was just how much wider the garter stitch swatch was than the stocking stitch swatch. You can imagine how this difference would multiply over 200 stitches. To get garter stitch fabric the same width as the stocking stitch fabric I had to go down 2 needle sizes.
In March I began working on a pullover project for a warm weather design in a cotton/linen blend called Zoey from Juniper Moon Farm. The yarn calls for a size 3-5 needle. I happened to have an old Boye size 5 needle handy the day I got the yarn so I swatched with it. I liked the look of the swatch and used the number of stitches per inch that I got to flesh out the pullover design idea on paper. The plan was to bring the project with me to Colorado that coming weekend. When I was packing up to go I decided to use the size 5 needles from my Addi Click interchangeable set I got for Christmas.
I casted on with my Addis and started mindlessly knitting along. The pullover begins with a garter stitch band of about an inch and then proceeds in stocking stitch. In a couple days after working about 30 rows, I stopped and pulled it over my head. It was huge. Insert gnashing of teeth here. After much measuring I discovered two things. First the gauge on the slick Addi needles was much looser than the gauge on the Boye needle I used to knit the swatch. I knew that going from a metal needle to a, say, much 'grabbier' bamboo needle would have changed my gauge significantly but I was not expecting such significant change in gauge using metal needles of different brands. The second thing I discovered is that garter stitch by it's nature compacts the stitches making them wider which was also adding to the huge-ness. Insert glass of wine here and then frogging back 30 rows of over 200 stitches each.
Something else worthy of a gauge discussion is that stocking stitch gauge when knitting in the round can be very different than the gauge you get when knitting stocking stitch back and forth in rows. More often than not it is because the tension is looser on purl rows (this is true for most knitters) and when knitting stocking stitch in the round there are no purl rows. So when a pattern calls for gauge 'in the round' you need to do a circular gauge swatch. Here is an easy way to do a circular gauge swatch that doesn't require casing on lots of stitches.
Now back to my pullover. After a time out for me and my needles, I refigured the number of stitches I would need for a neckline that fits and began again. It is a fun pattern--a flirty little cold-shoulder number. A few weeks later, sample completed (love it--pattern coming soon). I set out to determine actual gauge so I could size the pattern up and down. I was using my Boye Stitch and Row gauge checker and an old tape measure I pulled out of my sewing basket. The tape measure I normally use was in another project bag. I typically use the Boye checker to count the stitches per inch and then the tape to measure the sample to double check my numbers. Well... nothing was adding up. My gauge, multiplied out for the stitch/row count, did not match the width, length, or any other measurement the tape was coming up with on the sample. I spent a good deal of time rechecking everything and in total frustration decided to let it all rest for a day.
When I picked it up again I used the tape measure to count stitches per inch (because my Boye checker was in yet another project bag and out of reach) and I came up with a different gauge than I got with the Boye checker. WHAT???? There is of course only one, albeit totally unexpected explanation. Here they are side by side. Crazy. A ruler and a contractor's tape measure proved the Boye correct. I trashed the tape measure but wished I could have done something way more dramatic to it like throw it in a roaring fire and watch it melt. Slowly.
Lessons for today include always swatch with the needles you will be using to actually knit your project. Also, if the pattern's called for gauge is indicated as in the round, swatch in the round. Another thing to consider is that when a pattern calls for different size needles for say the body of the garment and the ribbing on the cuffs and bottom, using different sizes of the same brand needles will give you the best results. And, finally, you may want to double check your tape measure. Just saying.