Making Sleeves For Mail Armor
Tailoring chainmail sleeves can massively improve the armours overall weight, mobility and speed. Ideally, the mail should fit tightly around the arms and have no room to swing. At the same time, the joints need to be lager to allow full bending. Therefore a triangle shaped pocket can be inserted at the elbow.
Mail sleeve as shown in the Wallace Collection A13, 16th century 
Mail sleeve with triangle shaped pocket attached to the left side
For tapering the arm a stripe of mail can be inserted to create two smooth looking seams instead of one. In either way it’s best to place the seam at the bottom or lower backside of the armpit. Alternatively expansion rings can be distributed evenly around the sleeve.
Upper arm parts before connecting 
Tapered upper arm with two seams
