Don't be scared. I know it says "math" in the title, but it's
knitting math, so we can handle it, right? (Fearless knitters and all
that.) Plus, we'll go slow, we'll do this in stages, you can ask
questions, and there are no stupid questions, ever. OK. Now that you
know the basic concepts behind waist shaping, let's talk some numbers.

Waist shaping on a simple shirt: Hem to hip
We'll do the math for a theoretical sweater for myself, using my battered-and-beloved copy of Ann Budd's Knitter's Handy Book of Sweater Patterns as a template. I'll start with the charts for a basic pullover, modified to be worked in the round.
Remember, this is a theoretical sweater, folks. No time to knit an
actual sweater, but that's OK. It's just to illustrate The Numbers.
Gauge Swatch:
Yes, indeedie, I must theoretically knit a
theoretical gauge swatch, because I need to know two numbers: stitches
per inch, and rounds per inch.
Gauge: 7 stitches per inch and 13 rounds per inch.
Measurements:
For this part I need to know: hip circumference, hem-to-hip length, and
the all-important Desired Ease. For ease, I'd like something
body-skimming, but not tight. (No negative ease this time.)
Hips: 44" I measure this with my handy tape measure.
Hem-to-hip length: 2" I choose this based on the pattern and garment shape.
Ease: 1.5" (positive) ease I choose this based on how I like to wear garments of a similar style.
How many stitches to cast on?
Add together hip measurement and ease: 44" plus 1.5" equals 45.5".
Multiply by gauge: 45.5" times 7 sts per inch equals 318.5 sts.
Round up: 319 stitches to cast on at lower hem.
What to do next?
I start knitting! I work even over those 319 stitches for 2" (see
hem-to-hip length, above), which works out to 26 rounds (2" times 13
rounds per inch).
Once I have finished those 26 rounds, I have reached my widest bit. It is time for the decreases to begin!

Did you know we have a Techniques section?
Swatching checklist.
Measuring tutorial.
Find a good fit.
All about ease.

Sandi Wiseheart is the editor of Knitting Daily.
What's on Sandi's needles? I'm working away on the Gathered
Pullover, which spent some time in the meditation pond, and also on the
Secret Project. But I've also been spinning and beading and making all
kinds of crafty trouble.
Posted
Mar 11 2008, 04:00 PM
by
KD Sandi
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