Drafting a Two-Piece Tailored Sleeve

The arm at rest is not straight; it hangs slightly forward and bends at the elbow. A single-piece sleeve, drafted as a symmetrical tube, resists this and tends to twist or pull across the elbow. Splitting the sleeve into an upper and under piece lets the pattern maker build the forward curve and the elbow bend directly into the seams, so the sleeve follows the arm instead of fighting it.

The two seams, a forearm seam and a hindarm seam, are placed so neither shows from the front or the back in normal wear. This concealment, combined with the arm-following shape, is what separates a tailored sleeve from a casual set-in sleeve.

The upper sleeve is the larger piece, forming the visible outer surface of the arm and carrying most of the sleeve cap. The under sleeve is narrower and sits on the inner arm, hidden from view. The two are joined by the forearm seam on the front of the arm and the hindarm seam toward the back, both curved to shape the sleeve around the arm.

Because the under sleeve is smaller, the seams sit slightly inside the true side lines of the arm, tucked where they are not seen. The upper sleeve wraps around to meet them, giving the smooth uninterrupted outer surface that reads as quality.

• The whole sleeve is drafted with a curve toward the front, matching the arm's resting position.
• The forearm seam is hollowed so the sleeve bends forward at the elbow.
• The hindarm seam is shaped to give length on the outside of the bend.
• The wrist is angled forward so the finished sleeve hangs correctly with no twist.
• The cap eases into the armhole with the sleeve pitched slightly forward.

The elbow is where the sleeve must bend, and the two-piece construction handles it by shaping the hindarm seam with extra length on the outside of the elbow and slight suppression on the inside. This lets the sleeve curve at the elbow without the diagonal drag lines that plague a straight sleeve.

At the wrist, the tailored sleeve usually has a vent with buttons, formed by an extension on the upper and under sleeve at the hindarm seam. The vent is both functional and a signature detail, and it must be drafted as part of the sleeve rather than added afterward.

The two-piece sleeve cap carries ease, extra length in the cap that is eased into the smaller armhole to create the rounded, filled sleeve head of a tailored jacket. Typical cap ease is a few centimetres, distributed so the crown is smooth and free of puckers. Notches on the cap and armhole control where that ease sits.

Setting the sleeve is a skilled operation: the ease must be shrunk in with steam so the cap is round and smooth, and the sleeve must be pitched forward as it is set. Get the pitch or the ease wrong and even a perfectly drafted sleeve will hang badly.

A two-piece sleeve is defined by four curved seams and precise cap notches, all of which must digitize accurately for the forward curve and ease to reproduce. Minerva Patterns supplies tailored garments with their two-piece sleeves as DXF AAMA, PLT and PDF, with the cap ease notches, vent and forward pitch marked so the sleeve hangs as drafted.

The two-piece sleeve rewards precision more than almost any other pattern piece. When the curve, pitch and ease are right, the sleeve disappears into the jacket and simply follows the arm, which is exactly the effect fine tailoring is after.