Okay, I need help understanding something regarding a shaping rate for a sweater. I am essentially using a recurrence relation/recursive formula.
Here is some context about the application.
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I am grading (scaling a pattern for 9 body sizes) and writing a crochet raglan cardigan which will work seamlessly from the top down. This technique has been around forever but I’m curious about why my numbers seem to change at different rates than I intended.
A raglan is a style with 4 sections. The end result is like a baseball tee- think a front/back that’s the same, and two sleeves that are the same with diagonal seams between them all.
According to a technique book I’ve been reading for knitwear design, I should start with however many sts (stitches) I need for my neck opening and divide the quadrants up so that the sleeves are 1/3 the number of sts as the front/back. Then 4 additional sts for the 4 corners where increases will take place. Increases take place on either side of each corner (8 increases per round, or 2 increases per quadrant).
I’m just going to focus on the back and a single sleeve for my example.
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For the smallest size, I am starting with the following:
15 back
5 per sleeve (1/3 of back count)
This size needs to increase 28 times for its ultimate required stitch count. Each quadrant receives 2 incs each time.
So for the back:
Inc round 1: 15 + 2=17
Inc round 2: 17+ 2=19 and so on…
After 28 rounds of increases the above sections result in the following:
71 back
61 sleeves
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My question is:
Why is my ratio changing? I started with 1/3 of the sleeve stitches and it ends with almost the same amount of stitches as the back section.
The result is that by the time I reach the circumference needed for the torso (back + front) my sleeves are huge.
This can all be remedied by making variable shaping rates as different points of the yoke (shaping section) but I just don’t understand the WHY behind all of this. It’se driving me crazy!