Yowza! OK! I'm ALL for that, so here are two super-quick informal methods to adjust any "stockinette cylinder" sweater for the rising "v" shape evidently at issue. (Naturally, these methods will also work for anyone, male or female, with a chest significantly greater than their waist, but this particular post is pitched towards the fellows who got me started thinking about all this in the first place.)
METHOD 1: Graduated needle sizeHere's a handsome fellow in his graduated needle size jersey--4 different needle sizes were used to knit the scrap of fabric laying under this sketch of a body-builder and you can see the difference in gauge as the fabric climbs the rising V shape of this imaginary fellow's torso.
|graduated needle size method|
Here's how: Start by closely examining the sweater pattern schematic: you are looking for a sweater which will fit around the chest at the nipple line with the amount of ease deemed appropriate. Make up your gauge swatch until you get the stitch count for the fabric called for the pattern. (The nipple line is used because for many men's bodies, this represents the widest part of the chest, so this is the point of departure for garment chest measurements.)
For a standard stockinette-cylinder bottom-up sweater, start the sweater body with waste yarn--knit a few rows or rounds with yarn of the same weight as the sweater to be knit. The best waste yarns are acrylic or cotton, because these are easy to remove. You'll go back and take out the waste yarn at the end, working the bottom ribbing last. (When the ribbing is worked last, you can try the garment on, allowing you to perfectly adjust the length and bottom circumference of the ribbing in real time, rather than worrying about these measurements at the outset, when you really don't know how the garment is going to fit.)
In any event, after the waste knitting, commence to knit the sweater body with needles TWO sizes smaller than the ones needed to get gauge. Work until the garment reaches the lowest rib bone. Switch to needles 1 size smaller than those needed to get gauge (which would be one size larger than those used so far). Work until the garment reaches about the third rib bone (this might be a short-ish rise, that's OK--this short stretch is in the nature of a transition zone). Switch to the needles used to get gauge and work further. If the shoulders are in proportion to the chest, you can stay with these needles all the way up the rest of the garment. If the shoulders are not in proportion, but larger, then switch to one size larger needles 1/2 way up the armhole.
The sleeves are similarly started on needles two smaller, switched to 1 smaller partway up the forearm (how far up depends on the forearm development) then to the size used to get gauge somewhere around the elbow--again, this depends on the degree of arm development. For a disproportionately larger upper arm, switch to needles 1 larger just before the bicep bulge, otherwise, work to the top of the sleeve in the needles used to get gauge. Obviously, if making the garment in the round, it is easy to match the graduation in needle size, but if making up in pieces, be sure to take a note on which rows the change occurs, or you will have trouble matching up the pieces when sewing-up time comes, and there will be puckering and flaring.)
To nail down the needle changes with an example: suppose the sweater pattern you choose requires a gauge of 5 st/in at the chest. You would find which size needles you need to get this gauge--say for the sake or argument, a size 6. You would then knit the bottom of the sweater on size 4, switch to size 5 where the chest begins to flare--the bottom of the ribs, switch again to size 6 just before the nipple-line, at about the third rib up from the bottom. Stay with the size 6 all the way up, unless you need to accommodate some massive shoulders, in which case, switch to a size 7 halfway up the armhole.
Naturally, graduated needle size comprises an informal approach, and one which may not work on the most heroic figures--despite my strongman sketch-models, actual weight lifters and body builders are probably best advised to get out pencil and paper and do the actual math to figure a rising gauge, as well as actually adding to the stitch count. However, experience demonstrates that simply graduating the needle size does work for everyday body variations: many women have the identical problem, only just turned upside-down ("^" instead of "v") and this approach has successfully been part of my informal bag o'tricks for a long time--my oldest is 21, so these adjustments have been in use around here for a couple of decades, at least!
Method 2: ribbing
This handsome fellow sports a jersey knit in a 2x1 rib (k2, p1) and you can see how the ribbing stretches as it climbs the rising V shape of his body-builder torso.
This method has the potential to be even easier than graduated needle size. For this trick you simply work a standard stockinette "cylinder" sweater as instructed in the pattern, with the only change being the switch to ribbing, allowing the clinginess inherent in the fabric to overcome the sagging and bagging which would otherwise occur. For a sweater which fits around the chest in stockinette, a ribbed fabric will cause the garment to have a moderate amount of negative ease.
A 1x1 ribbing requires the least modification--being a multiple of 2+1 (ie: any odd number), the only change to the stitch count might be the addition or subtraction of a single stitch. Wider ribbings, such as 2x2 (a multiple of 4+2) or 3x1 (multiple of 4+3) and so on, take more adjustment to the initial stitch count.
Combo approachThe same needles were used to knit the entire ribbed scrap underlying the second sketch, with the nature of the ribbing itself providing the stretch. However, there is nothing to stop you from COMBINING these methods--using graduated needle size PLUS ribbing to get a really "v" shaped sweater.
A note on yarnsFor the graduated method, experience shows that lofty woolen yarns work best. A very tight twist could look stringy at the largest gauge while feeling stiff at the smallest gauge, but a loftier yarn takes the gauge change without either effect being particularly noticeable.