Sunday, June 20, 2010

Top-Down Design Tutorial 11: Figuring the Standard Yoke

Standard and saddle-shoulder yokes are relatively straightforward to calculate.

First, you need the back neck measurement, the shoulder measurement, and the sleeve cap measurement for the size you're making.

You'll start by making front right and left shoulders. Multiply your shoulder measurement by your stitch gauge. Cast on that number of stitches using a removable cast on for each shoulder. Knit until your front shoulders measure about one-third of your sleeve cap measurement, usually an inch or an inch and a half.

Leave your front shoulder stitches on a holder. Pick up and knit the right shoulder stitches from the cast-on edge. Multiply your back neck measurement by your stitch gauge and use the long-tail cast-on to cast on that number of stitches for the back neck. Pick up and knit the left shoulder stitches from the cast-on edge. These stitches together form the back of the sweater.

Work the wrong side row.

Work 1-3" of short rows across the shoulders and back to shape the shoulder slope. This puts more rows in the middle of the back than along the edges of the shoulders.

After you've finished shaping the shoulders with short rows, work even until the shoulder edge is the size of your sleeve cap measurement.

Your sweater will look like this:

The next step is to pick up the sleeves along the shoulder edge. Multiply your sleeve cap measurement by your stitch gauge. Pick up that number of stitches along each shoulder. Place markers to separate the sleeve sections from the body sections.

The corners at the edges of the sleeves are tight for the first several rows. You might need to pull your cable through at those spots in order to make that turn.

Next you'll need to figure out your arm increases. To find how many sleeve increases you'll need, take your desired sleeve width at the bicep and multiply by your stitch gauge. Add together the number of stitches you picked up for the sleeve cap, your underarm cast-on, and 4. Subtract that number from your desired sleeve stitches to get the number of sleeve increases you'll need. You'll do two sleeve increases on every increase row, so divide your sleeve increases by two to get the number of increase rows you need.

Subtract 2 from your underarm depth and multiply the result by your row gauge. This is the number of rows you have to do your sleeve and body increases. We'll call this number of rows the raglanline.

Divide your raglanline by your increase rows. Round up to the nearest even number.
That's your increase frequency. Now multiply your increase frequency by the number of increase rows and subtract that number from your raglanline to get the number of plain rows to be worked.

Subtract 5 from your sleeve increases. Work that number of sleeve increases at your calculated frequency. After that, you'll work the number of plain rows you calculated. Finally, you'll work 5 more sleeve increases at your calculated frequency.

Having figured the sleeve increases, you now calculate the body increases. Multiply your upper chest measurement by your stitch gauge. Subtract your back stitches from the desired upper chest stitches to find your upper chest increases. Divide by two to get the number of upper chest increase rows. Make those increases every other row at the beginning and end of the back and front sections of your sweater.

You'll work the back and front even (once you've filled in the front neck line) until just before the underarm. Take the desired full chest measurement, divide by two, and subtract your upper chest stitches from that to get the number of full chest increases you'll need. Divide by two to get the number of full chest increase rows.

Add the upper chest increase rows to the full chest increase rows to get the total increase rows you need. Subtract this number from the raglanline to get the number of rows to knit plain.

So, like with the sleeves, you'll first do the upper chest increases every other row. Next, you'll knit the plain rows even. Then, you'll work the full chest increases to the underarm.

As you're shaping the body, you're also shaping the sleeves and working the front neck:

See how the sweater is shaping up? Once you've joined the neck, you've done all the tricky knitting in the sweater.

And here's the neck being joined up:

And the sweater with half the body knit:

Thursday, June 17, 2010

All Sorts of Excitement

I've made some substantial improvements to the KnitFitter. Go over and check it out! (See sidebar.)

I've also used the KnitFitter to write patterns for all sizes of the poncho sweater for children. It's a plain text file with all of the patterns included.


Monday, June 7, 2010

Using the KnitFitter

If you're following my top-down design tutorial (see sidebar), you can use my open source KnitFitter program to do the math and write the knitting instructions for you.

The KnitFitter is a Python program. It takes an input file containing the following sweater fields and outputs the instruction for knitting the sweater. To run the KnitFitter program with the input file Mysweater.txt, type the following at a command prompt:

python Mysweater.txt

The input file contains parameters to specify the design and size of the sweater. Each parameter is specified by a keyword followed by a colon(:) followed by the value of the parameter. If you do not specify a parameter in the input file, the KnitFitter will use a default value.

The current input parameters are:

Patternname: {Name of Pattern}

The Pattername parameter is just a name for this particular sweater. It can be any string.

Sweatertype: [raglan, poncho, round yoke, saddle shoulder, standard]

The Sweatertype specifies the basic construction type of the sweater. It can be one of raglan, poncho, round yoke, saddle shoulder, or standard. The The default is a raglan sweater.

Style: [cardigan, pullover]

The style indicates whether the sweater opens in front or not. It can be either cardigan or pullover. The default is a pullover sweater.

Neckline: [crew, scoop, vee, shawl]

The Neckline specifies the type of neckline for the sweater. It can be one of crew, scoop, vee, or shawl. The default for poncho sweaters is a vee; the default for all other sweater types is a crew neck.

Neckdepth: {Neck depth}

The neck depth indicates the depth, in inches, of the front neck. This applies only to vee and scoop necks.

Sleeves: [none, tapered, rectangular, bell, puffed]

The Sleeves can be none, tapered, rectangular, bell or puffed. Currently, only tapered sleeves are implemented. Short sleeves can be specified by modifying the Sleevelength parameter in the sizing portion of the input file.

Mainstripe: {Main stripe}
Accentstripe: {Accent stripe}

Mainstripe and Accentstripe apply to poncho sweaters only. They indicate the length, in rounds, of the main and accent stripes on the sweater. When these numbers are specified, the KnitFitter uses them to fill in the back neck with an even stripe pattern.

Stitchgauge: {Stitch gauge}
Rowgauge: {Row gauge}
Diagonalgauge: {Diagonal gauge}

These three parameter specify the gauge at which the garment will be knit. The first two are the standard stitches and rows per inch from the knitter's gauge swatch. The Diagonalgauge is used only for poncho sweaters. It's needed because poncho sweaters are knit on the bias.

Sizingclass: [Men's, Women's, Child's]

The Sizingclass indicates which sizing table the KnitFitter should use to find standard sizes. The default is Women's.

Size: {Size}

The Size indicates which standard size to use. Children's sizes are 6 months, 1, 2, 3, 4, 5, 6, 8, 10, and 12. Women's sizes are even sizes based on chest measurements, 30-50. Men's sizes are even sizes based on chest measurements, 34-50. If you specify a standard size, all measurements are taken from the standard size chart.

The remaining parameters all specify custom sizing. They are only processed if the input file does not include a standard size. All measurements are in inches. The custom sizing parameters are as follows (shown here with their default values):

Backneck: 5
Underarmdepth: 10
Upperchest: 15
Chest: 40
Chestdepth: 3
Bodylength: 20
Sleevelength: 18
Upperarm: 16
Wrist: 8
Shoulder: 4
Sleevecap: 4

Saturday, June 5, 2010

Top-Down Design: Gloves without a Pattern


Death defying!

Watch as the intrepid knitter negotiates the tubes and bends of finger-down gloves without a pattern!

Or even a gauge swatch.

Gloves are one of the trickiest knits to fit well. They need to fit snugly, but not too tightly. The fingers need to be long enough but not so long that they're awkward at the fingertips. Those little tubes have a small tolerance for error.

Yarn for gloves should be smooth and strong and soft. Sock yarn works pretty well, but I usually prefer sport or DK weight. I like wool/silk blends for their combination of warm, lightness, and strength.

Gloves should be knit more tightly than hats or sweaters, but perhaps not quite as tightly as socks. If you're knitting with sock yarn, choose the recommended needle size or the same size needle you would use to knit socks. If you're knitting with DK or sport yarn, choose a needle a few sizes smaller than the one recommended on the label.

Cast on one stitch for the first finger. I like to knit my fingers in pairs using magic loop or two circs, but you can also knit them singly if you prefer.

Row 1: Knit in the front and back of your single stitch twice for a total of 4 stitches. Divide the four stitches for circular knitting.
Round 2: Knit in the front and back of each stitch for a total of 8 stitches.
Round 3: Knit

The next step is to guess how many stitches around you'll need for your index or ring finger. The aim here is to get glove fingers to fit each of your fingers. The index and ring fingers tend to be about the same size, smaller than the thumb or middle finger but bigger than the pinkie. By knitting those fingers first, you have a good chance of hitting the right diameter for at least some of your fingers.

First, guess your gauge (5, 6, 7, 8, or 9 stitches per inch). If you have small hands, your target (depending on your gauge) will be (10, 12, 14, 16, 18) stitches. If you have medium hands, your target will be (12, 14, 16, 18, 20) stitches. If you have large hands, your target will be (14, 16, 18, 20, 22) stitches.

Round 4: Increase evenly across the round to get your target number of stitches.

Knit a couple of inches and then try the tubelet on the fingers of the intended wearer.

If the tubelet fits any of the fingers snugly but comfortably, eureka! you have a finger.

If the tubelet is too big or too small for any of your fingers (this has never yet happened to me, but it could), guess how much bigger or smaller it would need to be to fit your index or ring finger. Rip out the tubelet and repeat the process until you have a finger.

Now keep knitting the finger until it is long enough. It should be a little (maybe a quarter of an inch) too short because the finger will stretch part of the hand to accommodate itself. For the thumb, measure to the top part of the hand where the thumb joins.

When you have your first pair of fingers, select a different target finger. The middle finger is about 20% bigger than the index and ring fingers, the thumb about 25% bigger, and the little finger about 20% smaller. Give or take, depending on the hand of the person you're knitting for.

Put your finished fingers on holders and keep making tubelets until you have snug homes for all your fingers:

When you've finished all your fingers, string an index finger, a middle finger, and a ring finger together onto your needles like this:

The fingers need to be joined together where they meet. Some people suggest that you knit the edge stitches of adjacent fingers together. I find that this leaves a hole, which I don't like. I take the four edge stitches of each finger (two on the front needle, two on the back) and graft them to the four edge stitches of the adjacent finger, leaving all stitches on the working needles.

The grafting is fiddly and time-consuming, satisfying to the knitting perfectionist, but probably onerous to everyone else. If you don't want to graft, just tuck the loose ends of yarn inside the fingers. When you've finished the gloves, you can go in and sew up any apparent holes.

When you have the three fingers together, knit a couple of rounds, a quarter inch or so, and then join the pinkies to the other fingers.

Knit one round with all four fingers.

Next round: *K3, k2 tog*

This will eliminate about 20% of the stitches. Knit a couple more rounds, then try the gloves on. If they look like they're going to be at all loose around the palms, do some more decreases. Keep decreasing, trying on, and knitting plain until you have a nice fit for the palm.

Note that I put the pinkies on the inside in this photo. This is the wrong way to do it. Put the pinkies on the outside and the thumbs on the inside. It makes the gloves easier to try on.

Knit straight until the palm of the glove comes down to the spot where the thumb joins.

Join the thumb in the exact way that you joined the other fingers. Place markers one stitch on the hand side of the former thumb stitches. You will use these stitches to make matched decreases every 3 rounds or so until you have eliminated all the former thumb stitches.

Keep knitting until all of the thumb stitches are gone. Try on the glove. With luck, it should be about wrist length by now. If not, continue even until it is.

Next round: *K3, k2tog* cheating enough so that your total number of stitches on each glove is an even multiple of 4.

Change to needles 2 or 3 sizes smaller than your working needles. Finish with a couple of inches of k2, p2 ribbing.

Saturday, May 29, 2010

Twisted Yarn

I've been knitting a pair of gloves with two colors, juggling four balls of yarn to simultaneously knit the two gloves on my circular needles.

I did my usual knitting-two-objects-at-once trick of putting each glove's yarn supply on a different side of me. By alternating whether I rotate the needles left or right, I can keep these two supplies from tangling.

The two colors used to knit each glove, however, were tangling badly. The yarn is a wool/silk blend that is both slippery and has a tendency to felt. I stopped every few inches to untangle the yarn, wishing there was an easier way to do this.

The slipperiness of the yarn was also causing it to unball somewhat, so I stuffed each ball in its own ziploc bag. That helped with the tendency of the balls to tangle, but the strands running from the balls to the gloves were still twisting and tangling.

One of the little plastic zippers accidentally closed around the yarn, bringing me up short.

It also gave me an idea.

If I stuffed as much of one strand of yarn as I could in the ziploc bag and zipped it shut, could I just dangle the ball and encourage it to unwind.

Yup. Who woulda thunk.

Monday, May 17, 2010

Unvented: Underarm Gusset

On the Broad Spiral Rib cardigan, I had an attractive Knotted Rib inset into the raglan line. As I was thinking about writing up the way I divide the arms from the body, I had an idea.

“Wouldn't it be handsome,” thought I, “if I continued the Knotted Rib through the underarm area and grafted it to the other side of the underarm? Then I could pick up along both edges of the Knotted Rib strip and have a little underarm gusset. It would probably help with the stretched stitches that I sometimes get in that area.”

The more I thought about this idea, the more I liked it.

When I got to the spot where I ordinarily do the underarm cast-on, I continued the Knotted Rib strip instead:

When I got to the end of the little strip, I grafted the end of the gusset to the Knotted Rib on the back raglan line:

At about this point, I briefly wondered if I was a little obsessed, knitting that little tiny strip and then grafting it to the other side. Could it possibly be worth the effort it was taking?

I continued knitting across the back, and then knitted and grafted the other little strip on the other underarm.

At the end of the row, I had underarms that looked like this:

Next, I picked up along the body edge of the gusset, muttering more things about how obsessive I can be in the knitting of the perfect sweater:

I'm very pleased with the results.

Top-Down Design Tutorial 10: Dividing the Arms from the Body

In all kinds of top-down sweaters, the yoke and arms are knit as a continuous unit to the underarm.

The yoke of the sweater has a cape form when you get to the underarm:

And here's the yoke open so you can see the shawl neck shaping:

When you get to the underarm, you knit the sleeve stitches to holders, dividing the arms from the body (oh, how gruesome):

The sleeve stitches on their holders:

The sleeve stitches stay on their holders while you knit the body.

On the first row after dividing the sleeves from the body, you cast on a few stitches at each underarm and then knit the body on down to the hem:

When the body is complete, you pick up along the underarm cast-on and knit the sleeves down in the round. Pick up the cast-on stitches and add two transition stitches at each end of the cast-on. If you don't pick up transition stitches, the corner stitches along the underarm will be stretched, leaving unsightly holes at the underarm. The transition stitches close the gap and make the fabric of the underarm smooth.

The steps for dividing the sleeves from the body:
  1. Knit one row, knitting the sleeve stitches onto holders.
  2. Knit back across body stitches only, casting on an inch or two of stitches at each underarm.
  3. Finish knitting the body of the sweater.
  4. Pick up the cast-on stitches along the sleeve edges of the underarms, adding 2 transition stitches at each end of the cast-on stitches.
  5. Knit the arms down in the round.

Saturday, April 17, 2010

Top-Down Design Tutorial 9: Figuring the Raglan Yoke

I recently updated my open-source KnitFitter project to do the calculations for round-yoke and raglan sweaters as well as for poncho sweaters.

I'd worked up a Broad Spiral Rib pattern in a lovely Peace Fleece yarn that I wanted to make into a zippered sweater. I put the gauge and my dimensions into the KnitFitter and tinkered with the raglan figuring until the program gave me a sensible answer.

This took a lot longer than I expected.

Raglans were the first sweaters I designed. I knit them exclusively for years. They're fairly straightforward to knit. They fit a wide variety of bodies nicely and work with a wide range of designs.

As I tinkered with my program, I discovered that getting the numbers right for raglan yokes is more complicated than I had realized. The logic for round-yoke sweaters is 15 lines long. The logic for raglans and poncho sweaters is 80 lines long, and it only covers the basics.

The good news is that figuring raglans is easier for humans than it is for computers. You just juggle things until they're right. You have a lot of options, a lot of factors you can fudge to get the numbers to come out right. Computers can't do that; they need to do things the same way every time.

A raglan has four or five distinct sections: the front (or left front and right front, if the sweater is a cardigan), the back, the left sleeve, and the right sleeve. Each section is separated by a raglan marker and one or more raglan line stitches. The increases for each section are done before and after the raglan markers.

In the Broad Spiral Rib Jacket, the five sections of the sweater are separated by a single Knotted Rib that emphasizes the raglan line.

Each section of the sweater grows from its initial width at the neck to the desired width at the underarm. Sleeve increases and body increases can be independent of one another; front and back increases can also be independent of one another.

The standard raglan instructions say to increase before and after each raglan marker until the sweater is wide enough and then to knit straight until the desired underarm depth is reached. For a lot of sweaters, this leads to a wide-enough sweater with appropriately-sized sleeves and an underarm somewhere in the neighborhood of the wearer's underarm. I find that this basic formula works well for children's sweaters worked in stockinette. For other stitch patterns or other sizes, it doesn't work well at all.

Okay, so a few numbers that we'll need to figure the raglan yoke:

Raglan rows: multiply the underarm depth of the wearer by the row gauge of the stitch pattern. This number tells us how many rows we have to make the raglan increases.

Sleeve stitches: multiply the desired sleeve width at the bicep by the stitch gauge.

Body stitches: multiply the chest measurement by the stitch gauge.

Neck stitches: the number of stitches cast on for the neck. In a basic crew-necked raglan, this is ((2 * back-neck) + 2) * stitch-gauge.

Underarm cast-on: A small number of stitches cast on at the underarm to form a gusset between the sleeves and the body and allow freedom of movement. In standard raglan sizes, this is usually an inch or two. I usually allow 1" for children's sizes and 1.5" for adult sizes. Multiply that number by the stitch gauge to get the underarm cast-on.

You have some variables to play with. You have a fair amount of wiggle room in dividing the neck stitches between the sleeves and body. You can adjust the underarm cast-on by a few stitches. You can undershoot the raglan rows by an inch or overshoot it by two inches.

Look at the numbers for neck stitches, body stitches, and sleeve stitches. About an inch of the neck is usually apportioned to each sleeve. So start by assigning an inch of stitches to each arm and divide the rest between the front and the back. Find the number of increases for each section by subtracting the neck stitches for that section and the underarm cast-on from the total number of stitches needed for that section.

Are the body and sleeve increases close to the same? If so, you might be able to juggle the neck stitches so that you can do the same number of increases on the sleeves as you do on the body. If not, the sleeves and the body will have to grow at a different rate.

Once you've juggled the neck stitches, figure the rate of increase for each section. Divide the number of increases you need to do by 2 to get the number of increase rows you need. Next, divide the raglan rows by the increase rows to get the increase rate. The increase rate tells you how often you'll need to do raglan increases for that section. If the increase rate is close to a whole number, your increase instructions for that section are simply Increase at beginning and end of section every [increase rate] rows until section is wide enough.

Now, if the increase rate is not close to a whole number, you'll have to do more fancy figuring to get those increases in. There are also stitch patterns where you don't want to increase on wrong side rows, so you might want to do more fancy figuring in those cases as well.

The simplest kind of fancy figuring is to round down to the nearest whole number, stop increasing when you have enough increases, and then work straight to the underarm depth. This conforms pretty well to the shape of the human body. The shoulders widen quickly, then the torso continues straight until the underarm. At the underarm, the sleeves and body of the sweater need to expand to form tubes around the arms and body. Ideal shaping for a sweater looks something like this:

Another option is to build a complex-angle raglan which conforms to the shape of the ideal sweater. This will fit better than a simple raglan. To build a complex angle raglan, you decide that you need to work so many increases, say, every row, and so many other increases, say, every other row. You put the more frequent increases towards the neck, saving an inch or two for just before the underarm and do the less frequent increases on the chest section where the body isn't changing.

Arms, luckily enough, follow a similar pattern. The sleeve cap can use a little extra ease, and the sleeve also needs extra width at the underarm.

Once you've figured out the rate of increases for each body section, you can write your pattern to the underarm.

Swatch Scarf

I found some Elizabeth Lavold Silky Wool on sale online, and I ordered a variety of colors thinking it would be good for gloves.

When it arrived, it didn't feel right for gloves. Not soft enough nor springy enough nor tough enough to make the sort of gloves I had in mind, anyway.

Yarn plays this sort of trick on me all the time. I buy it thinking it will work for one project only to swatch it and discover that it flat out refuses to become what I had in mind for it.

I have an old wool/silk scarf that I love, though, and the nubbly fine-textured yarn seemed like it would make fine scarves.

I leafed through my stitch treasuries looking for a good pattern stitch. I decided to start some leisurely swatching, knitting up some patterns I'd never tried before. I cast on 40 stitches and planned on working through about 4 inches each of Sailor's Rib, Twin Rib, Shadow Rib, Berry Stitch, Brioche Stitch, Wheat Ear Rib, Clove Stitch, Syncopated Brioche, Zigzag Knotted Rib, and Waffle Brioche.

I'd worked through four or five of the pattern stitches when my daughter casually asked, “Are you making a scarf?”

“Oh no,” I responded, “I'm making a gauge swatch of all these stitch patterns. When I finish, I'll choose one for the scarf, rip out the swatch, and knit the scarf.”

She looked at me as if I was slightly demented.

“It looks nice like that, with all those patterns together. Why don't you just make it longer and call it a scarf?”

So that is what I did.

There was one small catch. I hadn't included a side border stitch on the swatch. Some of the pattern stitches needed a border to look finished. The width of the pattern stitches also varied considerably, and a side border would help smooth the variations.

When the scarf was finished, I needed to pick up stitches on both sides and knit in a garter stitch border.

Fortunately, I'd started the whole endeavor with a few rows of garter stitch, so I was able to measure to deduce that 40 stitches of garter stitch equalled roughly 7.5 inches.

I marked 7.5" sections along the edges of the scarf. Fortunately, the scarf was 75" long, so the math came out even. (How often does that happen in knitting?)

Along each marked section, I picked up 40 stitches.

Okay, I didn't actually pick up 40 stitches. What I did was to pick up stitches in the most natural, consistent way possible. Then I counted them. When I had fewer than 40 stitches, I picked up the deficit evenly spaced across the span. When I had more than 40 stitches, I dropped the extras evenly across the span.

I've read a lot about different ways to pick up stitches, but I'm here to tell you it doesn't usually matter much as long as you pick them up consistently. You can pick up inside the outer loop (okay for bulky yarn in a reversible pattern), the inner loop, the running threads between the first and second column of stitches, etc. Each gives a slightly different look and might turn up an edge on the wrong side. Sometimes, you get loose stitches at the edge, but you can tighten them up by knitting them in the back loop to twist them shut.

When the scarf was finished, I thought it looked a little funky with its uneven edges, but it's a good color and undeniably warm. Several family members tried to stake claim to it, and Garry ended up scoring it.

My knitting project for my trip to Manhattan was another scarf from the same yarn, this time in Portcullis Stitch in three colors:

When I got back from New York, I was ripping the pages off my Stephanie Pearl McPhee knitting calendar. I chuckled at April 9th's You Know You Knit Too Much When... and Garry wanted to know what was so funny.

“You know you knit too much when you're glad your kids lost their mittens. You wanted to make more anyway.”

He looked at me with a twisty smile on his face and said, “Oh good. You'll be glad to know I lost one of my gloves, then.”

Wednesday, February 3, 2010

A-Knitting We Will Go

After the flurry of creative activity before Christmas, I've been relaxing with the next afghan.

I was shooting for 60" square, but it seems to be coming in at about 58" wide. It goes more quickly than the King-Sized Afghan, which is now serving as a very warm bedspread.

The new afghan has only eaten 3 balls of yarn so far and is only 14" long, so it still works as take-along knitting.

The other thing going on is this gauge swatch:

When I made the Twilit Forest Poncho Sweater, I dusted off my old perl program that does the number crunching for poncho sweaters and updated it so that it matches my current sweater design process.

Then I knit this gauge swatch. It's the raw material for a light zippered jacket, in a lovely spiral rib pattern that I used for Malcolm's Christmas concert vest. It will be a raglan with a little knot cable in the raglan lines and probably a fancier cable framing the zipper.

Yeah, well, I decided that, before I knit this sweater, I'd go ahead and port the poncho sweater program to Python and then expand it to do raglan design too.

The basic porting took a long weekend (and kisses to my wonderful husband for providing key support in getting started on this), and then I started looking at what I would really want a number-crunching sweater design program to do.

So I've been working on my vision for a top-down design program that would do the math to build sweaters the way I knit them. I have visions of neckline and sleeve variations, hooks for the sweater types I want to support, and a general mulling over of the best ways to specify and implement my ideas so that the program can do a lot of what I do when I design a sweater.

I'm excited about this. I've started an open-source project for the KnitFitter, and I invite anyone who is interested to pop over to sourceforge and take a look.