Tension and Slack

Drapery is influenced by what is underneath it. The body influences the clothing by putting tension on the active side of the motion, while the other side of the limb, or trailing side of the action, is the slack side.

Tension Folds

In the diagram showing the seated trousers, the rear and the knee holds the major points of tension. The back of the knee and the anterior side of the pelvis are the slack side of trousers, where the material gathers and the most extreme pipes occur. The slack side is made up of the material coming from the tense side of the trouser, thus the lines of influence point to the tension.

Slack Folds

The next example is a sweat shirt both at rest and pulled up. Pulled up there are a few folds that are caused by the elbow or the ridge muscles influencing the surface, but nothing too significant or demanding by design.

When gravity takes over we see all sorts of interesting clusters of material switch back and forth down the length of the arm with several mini half-locks within them. And from the shoulder where are several drop folds descending in a spiral fashion until the material bunches up at the elbow.

Combined folds

Due to the dense nature of the material with a lot of weight attributed to it, the material falls quickly to the inside of the elbow an as the arm flexes further, more material blisters around the first few half-locks. Every flex starts with a primary fold that half-locks, then secondary folds form and depending upon the type of material and the folds form the clothing will determine how many extra folds and how dense the pipes become as they form.