Wednesday, May 20, 2009

Knitting Rules of Thumb

Every so often, I come across an approximation that makes sense, is easy to remember, and I actually write down in my knitting notebook under the heading Cool Things That Are Easy to Remember but I Forget Anyway. I was flicking through said notebook the other day looking for something I have already forgotten about, and stumbled across the list. Because I am feeling way too lazy to photograph the center of the King Bat (aka Queen Ring) shawl that I finished a few days ago, I figured the list entries might come in handy for some of you. And make me feel less guilty about not stretching, pinning, photographing, cropping, uploading, and so on and so on.

Please remember that these are Rules of Thumb, not Inviolate Laws of Physics. If one or the other doesn't work every time, perhaps you could arrange for a different thumb or something.

  1. If you don't know what needle size might work best with a mystery yarn, thread the yarn through your needle gauge. The best fit is a good size to start with for regular knitting. For lace, try doubling the needle size.

  2. Don't want to (or can't) measure someone's foot? The length from the tip of the index finger to the base of the thumb is about equal to the length from the toe to where the foot connects to the leg (measured at the top of the foot). I discovered this one day when I put my sock over my hand. Why did I do that? I don't know.

  3. The measurement from the base of your thumb to the inside of your elbow is the same as the total length of your foot. Seems incredible, but it's true.

  4. If you stretch out your arms and measure from fingertip to fingertip, the length is the same as your height. You might find this useful when knitting shawls (Thanks, Carla!).

  5. The circumference of your wrist is about equal to the circumference of your foot at the arch. I have never needed to know what my arch circumference is, but I am sure there's someone out there who has been panting after this fact.

  6. The sleeves of an average sweater uses 1/3 of the total amount of yarn; the back takes 1/3, and the front 1/3. If you are not sure that you have enough yarn, knit the sleeves. Then you can adjust the body by, say, making it shorter, using a different yarn for the yoke, or blending in another dye lot.

  7. A cable takes about 10% more yarn than knitting the same stitches flat. This is an important rule of thumb if you decide to add some cables to a plain sweater--you'll need to cast on extra stitches or the fit of the sweater might be a big surprise. Actually, it would be a small surprise, but you know what I mean.

  8. Changing the size of your needle will change the gauge by about 1/2 stitch per inch for each needle size increment or decrement.

  9. One row of knitting uses about 3 times its length in yarn. This is a nice factoid for long-tail cast-on that eludes me every time I do a long-tail cast-on.

  10. According to the folks at Elann, if the gauge of a single strand of yarn is X stitches-per-inch, the gauge when used doubled will be X*.7.

  11. Also via Elann--if the project requires X ounces of yarn used single-stranded, it will require X*1.4 when used doubled.

  12. If you want to make a circular shawl, the general rule for increasing, is to increase four stitches every round, eight every other round, 12 every third round, or 16 every fourth round. There's some geometric flim-flam going on here. Please don't try to explain it to me.

  13. Eight increases/decreases every second round will give you a flat knitted circle. Six increases/decreases every round in single crochet will too.

  14. If you make six increases every second round, then knit x rows (where x is the number of rows with increases that you just made) then decrease six times every other row, you will get a ball.

  15. Two increases/decreases in the center of every second row will give you a 90 degree angle. That one’s pretty obvious, but it’s so useful.

  16. The last row of a project takes as long to knit as the rest of the entire sweater/sock/hat/scarf. This is a prime example of the Time Dilation effect.


Kitty Kitty said...

What an awesome list of rules of thumbs... Though some of them really make me want to pull a tape measure out tonight.

Have a great day

AnnieBee said...


Am I the only one surreptitiously trying to measure my foot against my hand/forearm right now?

PurpleBecca said...

This is a great list to have in one place, I think I'll print it out!

Anonymous said...

I knew a few of these, but so many that I had not heard of at all. Thanks!

Leslie said...

Having the "Curse of the Baby Hands" (short stubby fingers and never lost the dimples) I can tell you that law #2 doesn't always work. Law #4 will only work if your body isn't out of proportion (my arms are about 1" shorter than the average). I guess I'm just proving that I'm all about "not average" except I can say that Law #3 seems pretty apt!

If you don't mind, I'm printing this out and filing it with my CYCA and other assorted neat stuff. Thanks!

Brenda said...

Thanks for these great tips. can you explain in words for me #10? It says x asterik point 7. This must be higher math than what I remember from grade - oh let's say three. thanks.

Helen said...

That's fantastic - I must print it out and put it somewhere where I can find it... you don't know where that might be, do you?

fleegle said...

Dear Brenda--

The asterisk is shorthand for "times." So it's X times .7.

Mama Cat said...

I had to check one of these, because it felt so wrong to me.

The circumference of my wrist is 5 7/8". The circumference of my foot at the arch is 8 3/4". i.e., nowhere near the same thing at all.

Maybe I have extra-skinny wrists or extra-fat arches or something?

There are lots of other really cool things in that list though - thanks!

Carol said...

Since I am sitting at thecomputer in a tshirt and no socks (yes there are track pants in between) I measured my foot agains tmy elbow. my foot comes out short about an inch. I wonder if I am defective somehow???? Now there will be knitter's around the world feeling odd as they measure various body parts against others....

Laritza said...

Love it! printed and filed for reference.

Bunny Queen said...

Mama Cat - I'm in the same boat as you. I can circle my wrist with my opposite hand if I make my thumb and my middle finger meet. I just tried that with my foot and it only covers about 2/3 of the circumference. Sadly, I'm in a hotel and have no tape measure handy, so no exact measurements.

I did know the foot to arm ratio from (of all things) the movie "Pretty Woman". :)

Reluctant Penguin said...

These are wonderful! (Especially the last one.) I am printing them out to take to my knitting group later today.

Smitten Knitten said...

Great list. I can add it to my non-standard measuring tool kit along with my fiddly bit of string that I use when I don't have a tape measure handy so I know I need to make something about "this" long ;).

MJ said...

I love these rules of thumb--thanks for posting them. However, #4 depends on the individual. It's called Ape Index, and 0 is when your span matches your height. When your span is more, it's +1, +2, etc. When it's less, it's -1, -2, etc. (Learned this from rock climbing!)

Anonymous said...

I'm always happy to see a new post from you.
I really needed #8 yesterday. Too bad I only saw it today.

Anonymous said...

Love number 16 - except you forgot the corollary, that due to the time dilation effect, binding off a triangular shawl takes four times as long as knitting it in its entirety.

Your Ravelry friend MissValerie

kv said...

uh oh, by about rule number eight i started to go into a dissociative fugue.......maths were never my forte, so i guess it's going to be trial and error for me, still....sigh. but i really get why they're useful. more math equals less time doing the same thing over and over without getting a good result.

yarnlot said...

Never in my whole nursing training did I learn such interesting anatomy!
And imagine all those bloggers testing these rules, hilarious...

Jadielady said...

I must have a very small foot and even smaller hands for my size. Which actually I already knew, but funny to see that I'm truly not proportionate.

Lacefreak said...

Brilliant collection of the "rules". I have made a copy for myself because it is so awesome!

heidi said...

what a nice list!

thank you very much!

now, of course, I too have to try to remember it:)

Anonymous said...

Great! From your notebook to mine.

Thank you,


MoniqueB. said...

you're right. I've learned a lot.
May I add: if you can close your middlefinger and your thumb, that's the same size as your wrist. Both hands (thumb/thumb and middlefinger/middlefinger is a perfect fit on your neck.
And twice your ankle is once your tibia (upperleg?).
I've done artschool, and those are also drawingtips.
The hand is a perfect fit for your face too. It fits from top to bottom from your hairline to your chin. (and so on...).
i'm not quite a sockknitter, but i'll remember anyway.
But the gauge-rules are more then welcome.
thank you

heidi said...

thank you for your nice comment regarding my sweater:)

I really love knitting it, so I can forsee more fair isle sweaters in my future:)

and now, I've also printed out your excellent list! it will be useful:)

Oogie McGuire said...

Agree with all the people who are not average t that the measurements are not helpful. for example, wrist circ. is 6 inches arch circ is 9 inches. Other body measurements are equally off for me.

Batty said...

Wow... I think #2 just saved toe-up sock knitting for me! Thank you, thank you, thank you!

Batty said...

You need 106 kg of laceweight, you know you do! ; )

The destash yarn came today, and the color is perfect. I need to finish birthday socks for my parents (hence the secretive stuff around the blog, in case they peek), then I'm going to cast on some blue and yellow socks.

Mary Lou said...

Long Tail cast on rule of thumb - one inch of tail for each stitch you are going to cast on. This will be a little more than you need for thinner yarns, and you have to add a bit for very thick yarns. For casting on zillions of stitches, use an end from another ball, and you won't run out.