Sunday, December 7, 2008

Provisional cast on--knitting up vs. knitting down

Back in December '06, TECHknitting featured provisional crocheted cast on. That post promised a future trick to get around a long-standing problem--that there is ALWAYS going to be one fewer loop working down than working up. In October '07, this blog showed another method of provisional cast on: the COWYAK method. In the comments to that post, a reader touched on the same issue, writing...

"When I unzip my provisional cast-on, why are there one fewer stitches going "down" than going "up," AND, what can I do about it?"

Look at your hand. If you are like most people, you have five fingers. But how many spaces do you have between your fingers? For 5 fingers, there are only 4 spaces between your fingers.

The same thing happens in knitting when you work the other way from a provisional cast-on. If you cast on a certain number of stitches and work "up," when you "unzip" the provisional casting on, you'll have one fewer live stitches to knit "down."

In other words, if you provisionally cast on 10 stitches and then undo the cast on, there will only be nine stitches waiting for you to pick up to knit "down." It's not a mystery--it's just the same thing as your fingers--ten stitches knitted "up" leave only nine spaces between them, and that's what you're picking up with the provisional cast-on--the nine spaces.

Of course, the "spaces" analogy is not perfect--we obviously have loops on the needle, not spaces when we catch the live loops from a provisional cast on. However, like the spaces between our fingers, these loops are the bars between the stitches, they are the stitch TAILS, not the actual loops themselves.

Below is a view of what this would look like in real life if you removed the provisional cast-on, took the needles out, and could make the fabric lie flat. See that complicated business on the right and the loop on the left? That's what happens when you pull out the provisional casting-on: The half loops of the rightmost and leftmost tails get pulled upwards to the next row, leaving only the full loops of the tails between the upwards loops: 5 upward loops make 4 downward tails, 9 upward loops make 8 downward tails. In other words, the pattern remains the same: always one fewer downward loops than upward loops.


Now, the upside (har!) is that there are at least two elegant ways to solve this problem. Actually, there is a very good third method which involves an alternative to provisional casting on, and a link will be placed here when that post goes live. For now, however, the two techniques...

TECHnique #1:
Let's say that you want to knit on 8 stitches. Try this trick: provisionally cast on 9 stitches. On the first and second row, knit all 9 stitches. On the third row, knit 2 stitches together (k2tog) where you think they'll be least obvious. In plain stockinette, see if you like the k2tog right in the middle, or if you find an edge less obvious. I vote for the middle of the row, but you must make up your own mind. On the illustration below, the needles and the provisional cast off have been removed, and the fabric has magically been made to lie flat. As you can see, the k2tog is in the middle of the row, picked out for you in green. There were originally 9 stitches cast on and worked "up," leaving 8 tails. However, after the k2tog, there are a matching set of 8 live loops at the top and bottom of this work.


To summarize this technique:
  • Provisionally cast on one extra stitch
  • Row 1 and 2: Knit every stitch going "up"
  • Row 3: Somewhere along the third row, wherever you think it will be least obvious, k2tog to get rid of the extra stitch going "up."
  • Rows 4 and following: knit normally
  • when the time comes to "unzip" the provisional casting on, you will have the correct number of stitches to knit "down."
TECHnique #2:
If the trick of REMOVING an extra stitch going "up" doesn't grab you, here's another alternative which has you ADD an extra stitch going "down."

Provisionally cast on the correct number of stitches, and work all the stitches "up" normally. Unzip the provisional casting on, catch the live loops on your needle, and on the second or third row knitting "DOWN," add a stitch by the "invisible increase" method (click here for instructions).

To summarize this technique:
  • Provisionally cast on the correct number of stitches
  • Knit every stitch going "up"
  • When you come to unzip the provisional casting on, you will find one fewer loops going "down."
  • Pick up the stitches going "down" and knit for two rows.
  • On the third row, add a stitch by making a nearly invisible increase.
Provisional cast on makes a 1/2 stitch discontinuity--a jog-- between where the stitches go "up" and where they go "down."

Not only is there always one fewer stitch going "down" than "up," but the offset between the tails and loops causes another problem, also. Specifically, when we knit "down" on the tail loops, the downward knitting is 1/2 stitch off the upward knitting.

Through an act of heavenly mercy, it turns out that stockinette is so symmetrical that this 1/2 stitch difference is very nearly undetectable in stocking stitch. To prove this is so, take any piece of stockinette fabric, look at it closely, then turn it upside down and look again. You will see that stockinette looks the same upside down and right side up. The only way you'll see the offset in stockinette is at the edge of the fabric, where the 1/2 stitch jog shows as a tiny bump on each side.

Other knit fabrics are not so forgiving. A continuous ribbed fabric would show a 1/2 stitch discontinuity between where the stitches are knit "up" and where the stitches are knit "down." To minimize this, provisional cast on is usually used along a border where the fabric pattern is going to change anyway: the classic location is at the border between the bottom band and the body of a sweater, or at the border between cuff and sleeve. Because the bottom band or cuff is likely to be made in ribbing, while the garment body or sleeve is likely to be made in a different pattern, the discontinuity -- the jog -- of the provisional pick-up line is disguised.


A quick aside: Do you wonder why you'd want to put the cuff on a sleeve via a provisional cast on? There are at least two good reasons to do it: 1. It makes it easy to replace the cuff, important for children's clothing. 2. It makes it easy to adjust the cuff length after the main garment has been knitted and can be tried on. You might want to put the bottom band on a sweater via the provisional cast on method for the same reason: picking up the bottom band and knitting it last would make it easy to adjust the final sweater length after the sweater body has been knit and can be tried on.

If you were making a garment with just one fabric pattern -- a pattern which would look bad with a jog -- you would have to arrange matters so that at the line of the provisional cast on, there would be several rows of pain stockinette stitch.

A common example is lacy scarf worked in a directional lace pattern. Specifically, in order to have the two lace patterns match at the lower ends of the scarf, you might want to start the scarf in the middle with a provisional cast on, and work first towards one end, and then towards the other. However, you might not want the 1/2 stitch jog to interfere with the continuity of your lace pattern. A classic solution is to design the scarf with a stockinette panel, as shown below.

Because the provisional cast on is in the middle of a stockinette fabric, there will be hardly any visible discontinuity where the provisional cast on lies--there will be a 1/2 stitch jog at the edges, but none in the middle of the fabric. Also, the shape of a scarf with a narrow stockinette pattern lies very well on the neck--the narrow bit goes around the back, adding no bulk behind the neck, while the pretty lace panels show in all their glory on the front. The best part about a scarf like this is that the narrow stockinette band has the same number of stitches as the lace panels--no increasing is required. The secret is that lace (pretty nearly any lace) is much wider than a stockinette fabric on the same number of stitches, due to all the yarn overs.

There is a scarf like this somewhere here at Chez TECH, but one of the little TECHlings has it hidden away. When found, a photograph of it will be added to this post...

(Some time later) Oh here it is!

--TECHknitter
You have been reading TECHknitting on: "Provisional cast on --one extra stitch going up, one less stitch going down; 1/2 stitch off in pattern"

24 Comments:

Blogger FlippyTWS said...

It is so good to see you posting again. I am a completely self taught knitter and I've learned a lot from your blog. Thank you so much. I appreciate all the time it takes to type out and to create the diagrams, which I find very helpful to understanding exactly what you are talking about. Happy Holidays!

December 7, 2008 at 6:23 AM  
Blogger Sheila in Ohio said...

I am not a new knitter, but I am a basic knitter because I get so bored with a project when I can't progress because of lack of knowledge! Thank you very much for this fantastic blog; I know I will learn lots here.

If you don't mind keeping something on the radar for when it's appropriate, I read somewhere this morning of "double pick-up" knitting and I'm at a loss to find anyplace to explain it. I don't need it (yet), but curious as to how and why, to keep tucked away.

Thanks again... I am learning so much from all your current and older posts.

December 7, 2008 at 6:33 AM  
Anonymous heidi said...

I'm really happy that you're back again, and I really look forward to learn more from you!

and as always your tutorials are clear and precise!

December 7, 2008 at 7:37 AM  
Anonymous martha in mobile said...

I've known this as a fact for a good while, but learning WHY and HOW is exactly why I enjoy your blog so much. I'm glad you're back!

December 7, 2008 at 12:16 PM  
Anonymous Diane in Chico, CA said...

It's good to see you back in blogland. I appreciate you taking the time to do it!

December 7, 2008 at 1:27 PM  
Blogger ponka said...

I'm going to second everything FlippyTWS said!

December 7, 2008 at 2:09 PM  
Blogger femke said...

This is a great post! Thanks so much for sharing this info, especially the diagrams make it very clear. It must take a lot of time to put this together, but I really appreciate it!

December 8, 2008 at 6:18 AM  
Blogger Sanguiknity said...

I am also an internet-and-book-taught knitter and your blog posts are so helpful when I come across something new :) AND your blog posts are really organized so it's easy to find something I want to learn. Thanks!!

Mallory

December 9, 2008 at 12:50 AM  
Anonymous Ühltje said...

Thanks once again for your great advice. I have a slightly different way of doing this: My provisional cast-on is created by picking up the loops from a chained crochet thingie. when I do this, I pick up the first stitch and I then use both ends of the yarn for the next stitch. The rest of the stitches are single again. I then knit this doubled stitch as one, but when it is time to unzip the provisional cast-on, I use both loops as separate stitches, with the added bonus of not having an awkward last stitch without a support on the loop.

December 9, 2008 at 2:01 AM  
Anonymous Su said...

So glad you're back up! It was disheartening to discover such a great blog at sabbatical time. Thanks for very helpful information. As a book-taught knitter, but it's great to see these things put into such clear words and pictures. Aha! I'm doing something "right" after all!

December 9, 2008 at 8:15 PM  
Blogger jeaniewh said...

Welcome back - so glad to see you are posting again.

December 10, 2008 at 4:51 PM  
Blogger MtnViewJohn said...

Judy Becker's Magic Cast-on (Cat Bordhi's YouTube demo) is a provisional cast-on that has the same number of loops in each direction.

December 14, 2008 at 2:05 AM  
Anonymous Anonymous said...

Your illustrations are phenomenal.

December 14, 2008 at 6:45 AM  
Anonymous Anonymous said...

I always use a provisional cast on for welts when knitting with several/many colors. This gives me the option to decide after the sweater body is complete which color or color combos to use for the bands.

December 17, 2008 at 6:59 AM  
Anonymous Anonymous said...

Techknitter
In this tutorial you mentioned a third way to do a provisional cast on but I do not see it in the index; how do I find it?
I have three helmet liners knit to the place where the pattern says to cast on (some patterns say 59 stitches and another version of the same pattern says 60 stitches) additional stitches. Is it best to use the provisional cast on for this or the cast on mentioned in your alphabetical index casting on at the end of a row?
Another helmet liner question...
When I pick up stitches around the face part of the helmet liner: Bonnie Longs original pattern says to knit the ribbing around the face I think 1 1/2 -1 3/4 inches. Other supposedly new and improved revisions of her pattern say 1" ribbing around the face. (I kind of think that the other length of ribbing around the face might allow the helmet liner to drop down a little at the neck rather than pull up.)
Then I saw another pattern that had short rows knitted at the chin area, to supposedly make the helmet liner cover the nose without pulling up at the front. (That one is the Short Row Revision by Bonnie Evans.
Then there is another that is a gusseted helmet liner revised by Ellen m. Silva…she says it has a better decrease so that the ribbing is decreased more evenly around the face.
Have you ever thought about doing a tutorial on making helmet liners?
OOOOh gee whiz, how awesome would that be, any way you would consider it?
I have only made one but still don’t know a lot. Except that for the last row of castoff around the face I think I have a smooth decrease worked out.
I would just like to be able to provide helmet liners that fit and are what our military can use.
I know it is all personal preference what people want to knit but I want it to be the best I can do. Thankyou so much for your never ending help to all of us

February 13, 2010 at 11:55 PM  
Blogger TECHknitter said...

Hi Anonymous--I have a link for a fabulous resource:

http://www.ravelry.com/patterns/library/helmet-liner/people

If you go to that link on Ravelry (Ravelry=a networking site for knitters) you will find links to over 500 helmet liner projects, and the links (tabs) at the top of that page will lead you to lots of posts where the ins and outs of knitting them are discussed. If you are not yet a member of Ravelry, it's free to join, and it is SO worthwhile.

I believe you will find the answer to all your questions by poking around at the link above, and you'll be able to contact folks who have actually knit the liners.

Best--TK

PS: Thanks for making the liners! I'm sure our troops are very appreciative.

February 14, 2010 at 8:35 AM  
Anonymous sio said...

I wonder if you've grafted in ribbing. Do you have any tips? I want to avoid having a stockinette panel in this scarf (http://www.ravelry.com/patterns/library/scrunchable-scarf) which I plan on turning into a loop by joining the ends together. Any advice would be super helpful, thanks in advance!

December 1, 2010 at 10:04 AM  
Blogger TECHknitter said...

Hi Sio--I wrote an article about Kitchener stitching which appeared in the spring 2010 issue of Interweave Knits. That article does have instructions for grafting ribbing. Perhaps you can find this issue at a library? In spring of next year, the copyright for that article will revert to me, and then I will be able to re-publish the article on this website, but in the meanwhile, the magazine is the only place these instructions currently appear.

Best regards, TK

December 1, 2010 at 11:48 AM  
Blogger Becky said...

So what's the third method? :)

July 21, 2011 at 10:02 PM  
Blogger TECHknitter said...

Oooo Becky, that's a good question. I must have had something in mind when I wrote that cryptic note, but what, I wonder? I will leave that comment there for a while and see if anything comes back to me. Thanks for the heads up.

--TK

July 21, 2011 at 10:43 PM  
Blogger Genevieve said...

Thank you SO much!!! I've read and watched dozens (probably more) of how-to articles and videos on provisional cast on and NO ONE has ever mentioned this problem - I've been tearing my hair out for months thinking I was just doing it wrong, but I couldn't figure out /what/ I was doing wrong. It's nice to know that the missing stitch wasn't my poor knitting skill, but an actual and unavoidable consequence of the method - although it's also more than a little frustrating to find out that not a single one of my trusted Internet teachers found it worthwhile to mention such an obviously important issue! Anyway, thank you again - I've always found your blog clear and easy to understand (with EXCELLENT illustrations) and I've probably learned more from you than every other source combined because you always address and explain the little knitting mysteries that crop up so often, yet seem to off the radar of most knitting experts online who are teaching my generation this craft. Thank you again. You've once again proven that your site deserves to be my first stop when I want to learn a new technique or solve an old problem. Thank you!!!!

April 18, 2012 at 3:31 PM  
Anonymous Anonymous said...

Thank you for pointing out The Mystery of The Disappearing Stitch!

I'm a pretty expert knitter, but have never before knitted anything that required a provisional CO. I was feeling rather pleased with myself for executing one, from a crochet chain, on a cowl for Christmas, until I tried to unzip the crochet! I really thought I had created stitches from the correct 'bumps'... so it took ages to liberate the live loops! THEN...

I have just spent 2 hours trying to figure out where my 'lost' stitch had gone!

I am bookmarking your blog and making it my first port of call for any knitting know-how.

October 23, 2012 at 4:58 PM  
Anonymous Anonymous said...

Wow! You're so smart! Thank you for the very helpful information on the half-stitch conundrum.

January 17, 2013 at 8:29 AM  
Anonymous Anonymous said...

Wow! I so wish I had read this before I screwed up the wrap I've been working on! I couldn't figure out why the lace pattern was off, so I kept tinking because I thought I had done something wrong. Now I have a mess because I have gone back further than the provisional cast on and can't get the stitches organized because the yarn overs are confusing me. So glad to know I wasn't crazy. Great info. Thanks so much. Will bookmark for future reference!

May 11, 2013 at 11:08 AM  

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