Sorting out sleeves
It’s painful to knit a sweater, put it on, and have regrets about the sleeve length.
Sure, if you’re knitting top-down in the round you can try on as you go, but for that strategy to work you need to know for sure that your working gauge (your gauge before blocking) matches your blocked gauge, or you might still be unpleasantly surprised.
If you’re knitting another construction, or if you want to guarantee a nice shaping line, it pays to evaluate sleeve length before casting on.
What determines sleeve length?
For your sweater’s sleeves to be accurate, two measurements need to line up: your sweater’s back neck to cuff, and your body’s back neck to wrist.
Your body measurements
If at all possible, have someone help you with taking your measurements. Relaxed and with your arms down at your side, measure from the very tip of one shoulder to the other, across the back. Then, measure from the same tip down to where you want your cuff to hit your wrist. One-half of your shoulder-to-shoulder width + your arm length is the critical measurement we’re looking for.
Evaluate sweater measurements
Yoke sweaters: ½ back neck plus sleeve length
Raglan: ½ back neck plus raglan depth plus sleeve length. Raglan depth is the number of rows worked from the cast on to the underarm split (a vertical line) and is not the diagonal length of the raglan shaping.
Set in: ½ of the body width (typically front chest width) plus sleeve length.
Dropped shoulder: ½ of the body width, plus sleeve length.
Calculate your adjustment
If there’s a difference between the schematic measurements and your body – you need to make an adjustment. Subtract your body measurement from the schematic measurement - that's the amount by which the sleeves will pass your wrist.
A better fit at the shoulders
If you are working from a schematic that has a shoulder-width measurement, especially a set-in sleeve construction, you may want to evaluate whether you need to adjust only the sleeve or whether you should also adjust the width of the body.
Example: Your initial comparison shows your body measurements are 2” longer than that on the schematic. You are making a sweater with a set-in sleeve, which should have a chest width measurement that matches yours. You compare your chest width to the front width of the pattern, and see that your chest is 1” wider than that of the pattern. You should make the shoulders on your sweater 1” wider on each side, and only adjust the sleeves 1”.
If you are working a raglan, yoke, or another relaxed-fit garment, such a discrepancy is rarely critical, and you can adjust the sleeves. You may have a deeper or shallower raglan or yoke depth than shown on the pattern. Unless... you're in the wrong size.
Are you in the right size?
If you find you have a large discrepancy, either larger or smaller, this might be happening because you have chosen a size based on full chest measurement, and you might be better served by choosing a size based on upper chest measurement. See my blog post Upper chest - what, why and how for more info.
Making the adjustment
In general, the shaping of a sleeve from cuff to underarm will follow the general guidelines:
Work the cuff with no shaping.
Make a series of increases.
Make a series of increases further apart.
Work straight for 1-2 inches.
There are usually two increase rates because the number of rows required is not always tidily divided by the number of shaping rows required. The more closely spaced rate should be closer to the cuff. Why? Our arms change much more from the wrist to the elbow than from the elbow to the shoulder.
It’s tempting to fudge in any difference either at step 1 or step 4. And that works sometimes, especially if you’re only making a change of about a half-inch or so.
By working longer at the cuff, though, you run the risk of the sleeve not getting wide enough fast enough. By working longer at the underarm, you might add more material than you really want there. And by working less space at the underarm, you again run the risk of not having a wide enough sleeve at the fullest part of the arm. So go ahead and make some adjustments at the underarm – but try to make sure you have at least an inch before your underarm shaping.
The best way to make any length adjustments is to change the shaping rate. Unless you’re also modifying a width, you’re going to need the same number of shaping rows – but you can use your pattern’s gauge to determine how many additional or fewer rows you need to adjust. Once you have that number, simply adjust the frequency with which you work your shaping rows, keeping in mind that you want to work your more frequent shaping closer to the wrist.
Check out My Body Model! You can create a paid, personalized croquis - or even just input your measurements and see if that's something you might be interested in having. If you set up a free account and begin to put in your measurements, they offer a lovely comprehensive guide to taking your measurements. The My Body Model blog is a trove of information about fit and using a croquis for a planning tool.
Book a session! If you're overwhelmed with choosing a size, or need some guidance on making a modification (or would like one drafted for you) - book a 1:1 with me! I offer 30-minute 1:1 calls for knitters, and designers can learn more about working with me for grading consulting.