Monday 9 February 2009

M1 vs Kf/b

Samm (from the comments) asked for an explanation as to why you cannot use a M1 and a Kf/b interchangeably. So here we go.

A M1 is an increase which uses the horizontal bar or running thread between 2 stitches to make a new stitch.
M1– Make 1 stitch: With Left needle, lift the running thread between the stitch just worked and the next stitch, from front to back, and knit into the back of the resulting loop.
And a Kf/b (see below) uses 1 knit stitch to make a new knit stitch so that this 1 stitch becomes 2 stitches.
Kf/b: Increase of 1 stitch: Knit into the front of the next stitch as usual and without taking the stitch off the left needle, knit into the back of the same stitch.
They are both excellent increases. The Kf/b is easier to work and has a ton of applications. The problem with it is that it is not symmetrical. When you make the second stitch by knitting into the back of the stitch you produce a knit stitch and then a stitch with a bar across it. It's terrific if you are fitting it into ribbing because the second stitch mimics a purl stitch. This barred stitch is always to the left of the knit stitch. When doing increases for a top down garment I prefer the M1 because I don't get that second barred stitch. You can make the M1 stitch symmetrical so that it leans to the right or left.

My favourite is what I call the Open M1 which has no lean and doesn't make you stop in your tracks while you are knitting.
OPEN M1: (makes a small hole) Insert Right needle under the running thread between the stitch just worked and next stitch without lifting or twisting it, wrap wool around needle and complete as a normal knit stitch (similar to a pick up & knit).
It makes a small hole but it's not fiddly because it's just another knit stitch except under the horizontal bar instead of into a stitch on the needle.

Now, all that said I like all of these increases. The problem arises if you try to use a Kf/b when the instructions say to use a M1 increase. Example: If you have a section of 4 stitches and you are to work 2 increases written as: K1, M1, K2, M1, K1. You would knit 1 stitch, work the M1 increase between stitch#1 and stitch#2, knit stitch#2 and stitch#3, work the M1 increase after stitch#3, Knit stitch#4. Now you have 6 sts.
Here it is with the Open M1 with the little holes.
If you work the Kf/b increase instead of the M1 then you would knit 1 stitch, work into the front and back of stitch#2, knit 2 more sts (stitch#3 & stitch#4) and now you have run out of stitches and only increased 1 stitch. The increase is after stitch#3 instead of after stitch#2.

If you are very familiar with how these 2 increases work and want to use the Kf/b instead of the M1, you would write it as: Kf/b, K1, Kf/b, K1. Looks really different written down but gives you exactly the same result because the Kf part is a knit stitch and the b is the increase. I have NO problem if you can do the rewrite, none, nada. The problem is substituting one for the other without giving it some thought.Ahh, correct and lovely.
School is over. Was that a lecture or what?! Do you feel like you were sitting in a little tiny desk? You may all go out for recess now. No throwing snowballs and look out for the little kids on the playground. The knitting club will meet in the lunch room. You know where I'll be, out throwing snowballs, ha, ha.


  1. Wow, Deb, thanks!!! That was so beautifully explained and shown! I have used both increases, and often use KFB instead of M1, but I've always just automatically adjusted for that difference. :) I think I've become an intuitive knitter! I can see that it would make sense to follow instructions, though, in some cases, especially with the purl bump showing on the KFB. You've given me a lot to think about! Many thanks!!! Off to see if there's any snow left out back so I can get my snowballs ready. It has melted a lot the last few days, luckily without causing a mucky mess. It's wet wonderful packing snow now, though, what's left. My snowballs will be like bullets!!! samm

  2. That was *very* helpful! I would like to sub kfb for m1 in a sweater I'm knitting... but I think I'll just go ahead with the m1 after reading this. I think you just saved me a lot of frustration! Thank You!

  3. omg..thx a lot for this tutorial..cos i've been scratching my head on searching the difference between kfb & m1.. and found you blog about it.. you're my saviour

  4. Thank you for this lovely explanation - I have been wondering if there was a visible difference for days!

  5. thanks so much, you are brilliant...!!!

  6. I'm amazed. I've been knitting for years and never seen and "open m1". Thanks for opening my eyes to another wonderful technique. I love your top-down technique with children's clothes not only because of the no-sew result but because I enjoy seeing the garment grow from start to finish as I'm working.

    I also appreciate the helpful responses I've gotten to personal e-mail when I wanted to enlarge a pattern. You ladies are worth your combined weights in expensive yarns! :) Thank you from an ardent follower.

  7. I am knitting Christmas balls and the new pattern I found calls for m1 but I am more familiar with kfb. Do you think it would mess the pattern up if I used kfb. I'm not a new knitter but I'm just now teaching myself to really use increase an decreases. Thank you soo much!

    1. If you just sub in Kf/b for the M1 you will throw your stitch count out at the end of the round. You have to take into account that the Kf/b is using up one of the stitches of the round. So take out one stitch between increases: ie. K2, M1 becomes K1, Kf/b.

  8. Thanks so much. I was so confused as half the pattern of my symmetrical shawl used kfb and the second half m1. I'm still not totally sure why (bit thick) but see the difference now. Back to the needles!

  9. love ya for explaining it so well

  10. Thank you so much for this. I’m a newbie and working on a top down sweater (yoke style). I subbed the M1 stitch for the kfb because to me it’s easier, but my stitch counts were always off. Now I have a much better understanding and will learn the M1 now.

  11. Thank you for the great explanation, very clear. I knit mostly children's sweaters and prefer kfb for sleeves for two reasons--I like the look of the bumps and also it's easier to count rows! ;) After reading this, though, I think I'll try to open M1 for the next project. I like that look as well.


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