Knitting Math

I’m attempting to be more monogamous when it comes to my knitting.  I feel like I’m more of a process than product knitter, but it is still nice to actually get something off of the needles and wear it.  I’m working on clearing out my WIPs, most notably, my North Star Mittens which have been a WIP since July (JULY!).  I’ve got a whole list of things that I’d like to work on this year – both projects and new techniques and in an effort to get through them as quickly as I can, I think that monogamously knitting on one project at a time is best.  Of course, new habits are hard to break and I currently have 4 projects on the needles and will be casting on another in the next few days.  My excuse, not that I need one, is that two of those are long term scrap projects, and the other two are long term large pieces.   I’m knitting my first sweater and a large shawl out of fingering weight yarn!  Only the shawl is in fingering weight, not the sweater.  I’m not that crazy.  One thing I found myself doing a lot this week, while working on both projects, was a lot of knitting math. 

Now, I was a math major in college and I can say that, for me, knitting math is trivial.  It doesn’t bother me at all and I can follow the logic when other people try to explain how they customized their projects (such as lengthening sleeves or adding more waist shaping).  The first project, my sweater, has knitting math built right into the pattern.  It is the Abalone Cardigan by Hedgehog Fibers.  The pattern is free on their website and is only one page long!  Which, at first, threw me off.  I thought maybe you only got a preview for free and had to buy the full pattern.  Nope – the whole pattern is only a page long.  The second thing I noticed was that the pattern was only written for size smalls.  I am nowhere close to a size small and was about ready to toss this pattern aside but first, I read a bit further into the pattern and it gives directions on how to calculate the number of stitches you need for larger sizes. 

Now, I have a bad knitter confession to make: I’ve never knit a gauge swatch.  Never.  Granted, I never really strayed into very fitted garments and I was always happy with the results of my projects.  I don’t feel like I am a very tight or very loose knitter, so my projects always worked out in my favor.  Well, except this one pair of mittens where I was experimenting with going up a few needle sizes and yarn weight and didn’t re-figure the stitch count.  

I still wear these mittens in the winter so still not a total loss. 

 But I knew the importance of knitting a gauge swatch for both your actual gauge as well as the fabric you’re creating.  The pattern calls for a US 8 needle but the fabric I was getting was a bit too loose for my liking so I went down a needle size to a US 7 and the fabric I was getting was much more what I was looking for. I’m not sure if you can tell in the picture, but the top of this swatch was my fabric on US 8 and the bottom was knit with US 7.  The bottom fabric is just ever so much tighter. 

Excuse the wrinkly swatch, it has been living in my project bag and has gotten smushed.  It was nice and blocked at one point, I promise.  The pattern called for a gauge of 17.5 sts and 25 rows in 4” of stockinette and my gauge was 22 sts and 28 rows in 4” of stockinette.  Thus begins the knitting math.

The overall math was pretty simple.  The measurements I wanted for the cardigan was 39” around and if I’m getting 22 stitches for 4”, that means I’m getting 5.5 stitches for every inch.  Therefore 39” x 5.5 stitches/1” = 215 stitches. 

The pattern helpfully gives the stitch counts in percentage of total stitches as well.  The bottom of the cardigan is longer in the back and sloped so the instructions are to cast on 55% of the total stitches and then work a given increase pattern until you reach the total number of stitches you calculated above.  This is relatively simple math, and 55% of my final stitch count was 119 stitches.  So 215 – 119 gave me 96 stitches I needed to increase.  The increase pattern has you increasing 2 stiches each row so 96/2 = 48 rows.  So, I would need to cast on 119 stitches, work 48 rows in the increase pattern, and then I would have 215 stitches on my needles!  Easy peasy lemon squeezy. 

Now, I haven’t knit any other garments besides this one, but I really like this way of writing patterns.  I know it wouldn’t be possible for all types of sweaters, especially if they have complicated cables, lace, or colorwork.  But for simple patterns, having the percentage of stitches really helps.  I also think this would be an easy pattern to work in a different weight of yarn because all you would have to do is swatch to get a fabric you like and then just do the math!

The second major project I’m working on is the Celtic Myths shawl.  This pattern didn’t necessarily need some knitting math – it gave specific stitch numbers and shawls don’t normally come in different sizes.  However, I decided that instead of knitting it in a DK weight yarn as it called for, that I would use some fingering weight yarn that has been languishing in my stash.  Now, in my head, I knew that fingering weight is much thinner than DK weight.  However, the finished measurements for the shawl were 72” long.  So I figured maybe mine would end up closer to 60”, which is still a good sized shawl.  I was horribly mistaken.  I followed the pattern exactly from the garter tab cast on all the way through the increases until I had the number of stitches the pattern called for, and my shawl wasn’t even 30” long.  This shawl has an applied boarder so I needed to make sure that I had the correct number of stitches so I could complete a full pattern repeat of the boarder.  Luckily, the pattern had a little part with instructions on how to add more repeats if you want.  They gave a little formula of how to figure out how many boarder repeats you would need to do but I thought it was easier to just add multiple of 8 stitches.  The boarder pattern is 16 rows long, but you only pick up an edge stitch every other row – so you’d be picking up 8 stitches per repeat.  Then, I had to figure out my gauge and see how long I want the finished shawl to be an approximately how many stitches I’d need to get there.  You can see in these pictures that I tried a number of different options.

The original pattern had a total of 229 stitches which should give you a length of 72”.  With my fingering weight yarn, for a length of 70”, I need a total of 565 stitches!  So instead of doing 108 rows in the increase pattern, I have to do 276!  I think this would be a good pattern to have some smaller projects going at the same time.  That is a lot of plain stockinette knitting, with just a little eyelet pattern at the edge.  

I know I’ll have to do some more knitting math when I get to the sweater sleeves because the pattern doesn’t call for sleeves.  But I know that by taking a few measurements and some quick math, I should be able to get a good fit. 

Until next time,

Happy knitting!