to make the expansion, add a partial row of links (coloured red in the figure below), then add a second row on top of this, as shown. Next, add a complete row of links. This will mean joining two rings on different rows (blue links A and B in the figure) with a "crossing link" (purple link C). This process leaves a single idle ring (coloured green). Another complete row of links is then added. (This will involve joining the links labelled C and D in the figure.) You can now continue to add rows as normal. The result will look crooked at first, but this will sort itself out once you've added enough rows. Note that the "hole" row contraction can also be used in reverse to add rows, and the "knot" row expansion can be used for contractions. In the hauberk described below, the "knot" method is avoided in the sleeves, probably because the idle rings would tend to catch and be uncomfortable. The "hole" method is used instead: the small gaps this construction leaves would be unlikely to cause problems, as they are on the underside of the sleeves. Regardless of the method you use, you can only add or subtract rows in pairs, for reasons that should be obvious! The medieval armourer probably did not work from written patterns but rather from experience and a mental concept of how the finished article should fit. I recommend that you work in the same manner. First plan how