Thursday, March 24, 2016

The math behind self striping

I recently asked some of my fellow knitters/dyers what types of things they would like to see on my blog, and one of the requests I got was to talk about how to do the math for self striping.  So before I talk about how I actually dye self striping yarn, I thought I would cover that topic first.

Self-striping is a labour of love, and many dyers have a love/hate relationship with it. They love the way it turns out, but hate the process. Many of us will make a colour way then declare it is too much work and that we are never going to to do it again, and then find ourselves planning out the next one as soon as we start knitting with the last one we did.

I have three methods that I have used for this, and I will admit that at least one of them in not perfect. But before I get into the method, there is one thing I want to stress - self striping is not an exact science, so cut yourself some slack. The dye may bleed into the section next to it, changing the length of your stripe. Or you may think you have measured correctly, just to find out once section is shorter or longer than the rest.  It's all good. No one (except maybe you) is ever going to examine the yarn or the finished item and declare that it is imperfect because one stripe is off by a couple inches. If there is someone in your life that would do that, don't show them your yarn. you don't need that kind of negativity when doing something that is so much fun.

Method 1 - I guess
Yup... you read that right. For my first self striping yarn, I did some basic math with absolutely no basis behind it other than I knew how to divide. 

I looked at how long of a skein I could make (50 feet),  figured out how many colours I wanted (5 sounded good and was easy math) and did the math, having absolutely not clue how long my stripes were going to be.   That skein had sections that were 10 feet long, and it gave me stripes that were about 4 rows wide.
My birthday socks from 2015
My very first ever self-striping yarn
Not all of the stripes are exactly the same size because I didn't tie my markers tight enough and a few of them slipped while I was dyeing the yarn. I also didn't measure as well as I thought I did and the skein wound up with one section that was longer than 10 feet (I think it was the pink section). More on that process in the How To - Self Striping post.

Method 2 - I measure another self striping yarn
I thought of this after I had made a couple of my own skeins of self striping. I found a couple of leftovers in my stash from some yarn that I had used before to make socks with, and that I liked the thickness of the stripes, and pulled out the measuring tape.  Note: The yarn in this picture is NOT one that I dyed myself. This is a commercially dyed one that I pulled out and measured.  

For the yarn pictured, the red stripe was approximately 16.5 feet long, and the brown was approximately 25 feet.
Knit Picks Felici Sport in Boutique 

Method 3 - Knit, mark, rip, measure
I will admit that this is my least favourite of all of the methods, because I don't like to knit something for the express purpose of ripping it apart. But it can be one of the best ways to get the thickness of stripes you are looking for.

You will need to use the same yarn you are planning on dyeing, but do not use the bare yarn.  Yarn blooms when dyed and shrinks when dried, so you want to use a sample of the same yarn that has already been dyed and dried, to get a true measurement.  Knit up a swatch of whatever pattern you want to use, and make it about two to three times the size of the stripes you want.  This way you can get an average and don't have to worry about tension changes. If I am dyeing for socks, which I usually always am, I will actually knit the pattern in the round, to get the best possible results. Unless the sock is all going to be in a ribbed stitch, I don't knit the ribbing, but knit whatever pattern the majority of the leg/top of the foot is going to be. 

Mark the beginning of the yarn. I use a Sharpie, so make sure it is yarn you don't need for something else, or else tie a piece of scrap yarn extremely tight around that spot.  And I mean death grip tight, because you do not want to go through all of this just to find the yarn has slipped out of place and you have to do it again (been here, done that). Do the same at the other end of the swatch you have knit.  Now, take the swatch off the needles, take a deep breath, and pull the swatch apart.  Measure your yarn and divide by how many stripes you wanted to have in that section. 

A note about shrinkage - Your yarn is going to shrink when you dye and dry it. That is just how it goes. The yarn blooms and then shrinks, so you may want to keep this in mind when sectioning out your yarn.  I have found that 12 foot section of yarn will lose about 6 inches when it is dyed and dried, so that is about half an inch per foot.  This is not an exact measurement (as I said before, the colour will bleed and that may change the length of the section of yarn), but it is a good average for me to keep in mind when I am dyeing this particular yarn (Opal Bare in fingering weight).  The shrink of your yarn may vary, so you have to decide if this is enough of a concern for you to measure your first self striping in that yarn and use that measurement on subsequent skeins. I personally don't find this is enough to have a whole lot of impact on my stripes unless my sections are only a few feet long (for really thin stripes) And even then, it is personal preference. I try not to let my OCD tendencies get involved in my self striping yarn, otherwise I will drive myself nuts. 

Not every yarn is going to work out exactly as you had planned, but that is okay
I really could put this disclaimer on the top of every page, but I wanted to point it out here for sure. I recently tried to do one skein where I would have just one row of a darker colour on either side of a lighter colour stripe. I thought I had measured properly, but when I knit my sock, it turned out I had 1.5 rows on either side of the thicker rows.
Opal Bare fingering in my own Speckled Easter Egg colorway

I learned three things from this colourway - don't try to get as precise as one row of a stripe, I prefer having a thin stripe that is at least two rows thick on either side of the thicker row, and the person who got the socks only every sees the awesome colours and cool socks you made for them.When I gave these socks to their new owners, she never noticed it. In fact, the only people who really seemed to notice it were people I pointed it out to...

I hope this post has given you enough information to get you started thinking about your first/next skein of self striping yarn.  My next post will go through my various methods for creating my self striping, from how I make my skeins to the various ways you can dye your sections of yarn.  And hopefully, by the time I finish that one, I will have found/taken all the shots I need to update my How To - Hand Painted post as well.  Tomorrow is a holiday, so that should help :)


  1. I can't wait for the how to post!!

    1. I may have to break it up into two on how to get the size skein you need, and then one on the actually dyeing process. Either way, there should be another one either later today or tomorrow :)