Fashion Academy · Garment anatomy
A sleeve covers part or all of the arm, but its fit depends on a precise relationship between the sleeve head and the bodice armhole. This lesson uses a classic long set-in shirt sleeve to make that construction visible. Raglan, kimono, cap, bishop and tailored two-piece sleeves reorganise the same jobs in different ways.
From shoulder to cuff
Each mark has a practical job. Together they control orientation, movement, hang and the clean finish at the wrist.
01
The sleeve cap, sometimes called the sleeve head, is the curved upper edge of a set-in sleeve. It must correspond to the shape and length of the bodice armhole, but it is not simply a copy of that curve. Its height and width influence appearance and movement. A higher cap usually looks more tailored and gives a narrower arm angle, while a lower cap tends to support easier movement. Accurate stitching around this curve prevents drag lines and unwanted fullness.
02
The shoulder point is the highest position on the sleeve cap and normally aligns with the shoulder seam of the bodice. This match point keeps the sleeve centred on the arm. If it shifts forwards or backwards, the sleeve can twist and the grainline may no longer hang vertically. The point is marked on the pattern and transferred clearly to the fabric, then matched before the remaining cap is distributed around the armhole.
03
The front notch identifies the part of the sleeve that belongs to the front armhole. On many patterns it is a single notch, giving a quick orientation check before sewing. This matters because the front and back cap curves are shaped differently to reflect the body. A sleeve inserted the wrong way round may still reach the armhole, but it will usually twist, restrict movement and create confusing drag lines near the upper arm.
04
The back sleeve is commonly marked with a double notch, distinguishing it from the single front notch. These marks align with corresponding points on the back armhole and help control the section where cap ease is distributed. Notches should be shallow enough to remain within the seam allowance. If they are clipped too deeply, they can weaken the seam or remain visible after construction.
05
The armscye seam joins the sleeve cap to the garment armhole. It travels around a three-dimensional curve, so careful preparation matters more than speed. The sleeve and bodice are matched at the shoulder point, front notch, back notches and underarm positions before stitching. Seam allowances may be neatened together or separately according to the fabric and design. Good pressing over a sleeve board or tailor's ham helps the seam settle smoothly around the shoulder.
06
Cap ease is the small amount of sleeve-cap length that exceeds the matching armhole between the notches. It allows the sleeve to curve over the shoulder rather than sitting flat. The extra length is eased in smoothly, not gathered into visible tucks, unless the design deliberately calls for fullness. The correct amount varies with the pattern, fabric and sleeve style. Wool can accept more shaping than a crisp fabric that resists compression.
07
The biceps line crosses the sleeve near the fullest part of the upper arm and is normally the widest horizontal measurement on a basic sleeve pattern. It needs enough wearing ease for the arm to bend and lift without pulling the bodice out of position. Too little room creates horizontal strain lines and restricted movement. Too much can make the sleeve look heavy. Measuring the finished sleeve at this level is often more useful than relying only on a size label.
08
The grainline runs lengthwise through the sleeve and should hang straight from the shoulder towards the wrist. On a woven sleeve it is usually placed parallel to the fabric's lengthwise grain. Accurate placement helps both sleeves behave consistently and prevents spiralling. The grainline is also a useful fitting reference: if it swings towards the front or back on the body, the sleeve may be rotated incorrectly or the cap balance may need adjustment.
09
The underarm seam closes the sleeve into a tube from the lower armhole to the wrist. On many garments it meets the bodice side seam, creating a continuous construction line, although this can vary. The seam shapes the sleeve width and may curve slightly to follow the arm. Matching the front and back edges without stretching them keeps the wrist level. Its finish should suit the fabric, because bulky seam allowances can feel uncomfortable against the arm.
10
The elbow line marks the level where the arm naturally bends. A basic one-piece sleeve may gain comfort through subtle seam shaping, while tailored sleeves can use an elbow dart or a two-piece construction for a more permanent bend. The goal is movement without excess fabric collapsing around the joint. During fitting, bend the arm rather than judging the sleeve only in a straight pose. That simple test reveals whether the length and ease are working.
11
The wrist opening is the lower circumference of the sleeve before the cuff is attached. It must be wide enough for the hand to pass through when the placket is open, then be controlled to the cuff measurement with pleats or gathers. The opening should sit at the intended wrist level on both arms. A badly balanced lower edge can make one side of the cuff dip or cause the sleeve to twist.
12
The sleeve placket is a finished slit near the back of a shirt sleeve that allows the wrist opening to expand. It may use a narrow continuous binding or a shaped tower placket. The top of the slit needs secure stitching because it receives repeated stress when the cuff opens. Placement is important: the placket should fall towards the back of the wrist, and both sleeves should mirror one another rather than being cut identically.
13
The cuff is the structured band finishing the wrist. It encloses the gathered or pleated sleeve edge and creates a controlled opening with a button, stud or other fastening. Interfacing gives the cuff enough body to hold its shape, but its weight should suit the fabric. The overlap direction, button position and finished circumference affect comfort. Before attaching it, check that the placket, pleats and underarm seam are arranged consistently on both sleeves.
A good sleeve is not judged only while the arm hangs straight. It should remain balanced when the wearer reaches, bends and moves, because the best construction follows the body instead of merely outlining it.
