Expert: Lesley Arnold-Hopkins - 3/3/2009

Question
QUESTION: Im having a very difficult time sizing up a pattern the pattern calls for 32-34 in bust. I need 38 in bust. in using woorsted weight yarn and size 7 needles. the pattern is asking to cast on 44 sts,
Row 1: K1 *wl fwd., Sl 1, K1* repeat till 1 remains Sl1.
Row 2: K2tog *wl fwd., Sl 1 K2tog* repeat till 1 remains. I cannot seem to get it increased so 1 remains. Help.

ANSWER: Hello Cherie,

Thanks for your question.

Is there something missing from the knitting instruction? Over 44 sts, I can't get it so that 1 remains either!

Is there a "wl fwd" missing just before the last sl 1?

The first row pattern works for any even number, but the second row pattern needs a multiple of three. This would only work if there is one more increase, as far as I can see.

In terms of sizing, then if 44 sts are needed for a 32" bust:
44/32 = 1.375.
1.375 x 38 = 52.25 (52 sts).

Obviously, check as you go along that this makes a reasonable fit and don't forget that the neck doesn't need to be much bigger, just because of the bust size change.

I hope that this helps, but please let me know if I can be of any more assistance.

Thanks

Lesley



---------- FOLLOW-UP ----------

QUESTION: http://www.vintagepurls.net.nz/Downloads/Lux1951TubeTop.pdf
Here is the pattern. I guess i did forget a Sl on the first row. Sorry! That formula, Can you use that on any pattern? Will it still work if I move it up to 40"? Even and Odd numbers does it matter?

Answer
Hi Cherie,

Thanks for the reply and thanks for sending the link to the pattern - this helps a great deal.


With regard to the sizing, yes the formula could work as, essentially, knitting is just maths. Just remember to check that it fits in with the multiples needed for the stitch pattern, in this case, multiples of 3 (for each sl1 purlwise, k2tog) and 3 edge sts (k2 tog at the beginning and sl1 purlwise at the end).

Given that this is a very fitted item, you may also like to check the ease, rather than just bulking up the figures.

The original tension is 5 sts per inch. At its fullest part, the bust of the top as 76 sts on each half, which would give you 15.2", or 30.4 for the total bust. Given that this is to fit a size 32-34 (we'll work this out on 33" as an average), then the garment is 2.6" smaller than the actual bust size, or a negative ease of 2.6" (8%, approx).

Therefore, if you wanted to make a size 40" bust, with the same amount of "grip"(!), you would need your top to be 36.8" round, or 18.4" (92 sts) each piece at the fullest part.

Working the shaping back, (and I'm re-writing the pattern backwards here, from where it says "work 6 rows").

3rd repeat of decrease   88 sts
2nd repeat of decrease   84 sts
1st repeat of decrease   80 sts
1st decrease          76 sts

However, 76 is not divisible by 3 (which is what we need for the stitch repeat) but 78 is.




If you're ending up with 78 sts at the end of row 1, what do you need to cast on with?

To work the pattern forward:
44 sts less 2 edge sts = 42. Divided by 2, this is 21 and multiplied by 3, this is 63, 63 plus your three edge stitches (allowing for the wl forward befor the last st) gives you 66 sts for the original 32" size.

To work this backwards, we want to end up with 78 sts.

78 - 3(edge sts) = 75
71/3 = 25
25 x 2 = 50, plus 2 edge sts, means a cast on row of 52 sts.

Which, co-incidentally, is close to what we came up with in the first place, but this will hopefully give you some idea about ease and proportion, for altering patterns.

I'm sorry that this was a bit long winded in places, but it will hopefully show you that, with the aid of a calculator, any pattern can be re-sized.

It's on a slightly different tack, but I wrote a short series of articles about knitwear design (using the same principles), if they are of any interest.

http://www.suite101.com/functions/article/edit.cfm/46023

Thanks again for your question, and happy knitting!