Feeling ambitious?

Anybody remember my Reversible Celtic Baby Blanket pattern?

Those two photos there are of the same blanket (hence the word "reversible" in the pattern name). The reversibility is achieved using the double knitting technique. This translates into 482 stitches per row for 241 rows, to create a blanket about 35"x58". If you haven't figured it out already, this project is kind of a beast!

Recently, I got contacted by a knitter who wanted advice on how to turn it into...wait for it...a blanket for a king-size bed. (If you need to lie down after reading that, I understand. Take your time; this post will still be here when you get back.)

I myself have a predilection for projects which other knitters may consider insane in their scope, so I definitely wasn't going to discourage her! But I did want to give her a realistic idea of what she was letting herself in for, and I definitely didn't want her to waste scads of time on solutions that would turn out poorly. So I came up with a bunch of information and suggestions for her. I then figured I should share all that here, in case there's anyone else who felt like taking on an absolutely massive project. :)

So here we go: What to think about if you want this pattern as a king-size blanket

Firstly, such a project pits you up against a number of challenges:

1. The length-to-width ratio of the pattern as written is 1.65. However, a king-size blanket should be about 90"x108" (source: beddingstyle.com), which is a length-to-width ratio of only 1.2. This is quite different from 1.65.
   
2. Knitting a king-size blanket all in one piece is probably not a great idea. For one thing, with measurements of about 90"x108", you'd need a circular which can handle up to 108" worth of stitches. For another thing, the weight of the blanket as you knit it is going to be pretty crazy, and will only get worse as the blanket gets bigger. (Remember that this is a double knitted blanket, which means it'll be twice as thick and therefore twice as heavy as a regular blanket knitted with the same yarn.)
   
3. You may be thinking that one way of making the blanket bigger is to increase the number of repeats of the centre motif. However, this is unlikely to work well. Why? Because with the pattern as it is now, the math works exactly right with the key pattern on the borders. What I mean by this is: (Warning: math ahead; please feel free to ignore and skip ahead to my recommendation if you are not a math person.)
   • Centre pattern count: repeat-of-72 + 11
   • Border pattern count: repeat-of-30 + 5
   • As the blanket is written, you do two repeats of 72 for the centre pattern, both widthwise and lengthwise.
   • Therefore, the entire centre section is 155x155 (because 11 + 72x2 = 155)
   • This perfectly matches with the border, because (remembering that the border pattern count is repeat-of-30 + 5) 155 minus 5 is evenly divisible by a 30-stitch (or 30-row) repeat.
   What this means is that if you decide to increase to, for example, three repeats of the centre pattern, this will give you a centre section of 227x227 (11 + 72x3 = 227). However, 227 minus 5 is not evenly divisible by 30, so the border isn’t going to match up!
   
   The only number of repeats of the centre motif which are going to work is repeat-of-5 + 2 (i.e. 2, 7, 12, 17, etc.). And even expanding it to just 7 repeats instead of 2 is going to wildly increase the number of stitches in each row - instead of 482, you’ll have 1202.
   

So.

Given all of the above facts:

• Simply using thicker yarn and needles won't work, because you'll still be stuck with a 1.65 length-to-width ratio, which won't work for a king-size blanket.
• Increasing the number of repeats of the centre motif isn't really practical either.
• Knitting the blanket all in one piece isn't the sanest way to go anyway.

Therefore, what I ended up recommending was:

1. Use 3.75mm needles instead of 4mms. 
2. Make the blanket six times. 
3. Sew the six blankets together.

This works best (in my opinion) because:

• Using 3.75mm needles will probably reduce each blanket from 35”x58” to about 32.8”x54.4”.
• You can then sew the six blankets together so that you have about 108.8” in one direction (54.4” x 2) and about 98.4” in another direction (32.8” x 3). 
• 98.4”x108.8” is very close to 90”x108”.
• No need to make the blanket all in one piece.

It’s not going to look exactly the same as having a single border surrounding a centre motif, but I think it’s the best bet.

Hope this helps!