Pleat Swing Physics?

[Bugbear]

Ya, and it would have a bit of a twist across the surfaces because it is steeked near the bottom of the fell... That would mean that the inside edge is moving a different amount... posibly even in the oppizit direction from the outside edge of the pleat.

If that is the case the flexability of the fabric in the bias direction also may play a role in this movement.

The reason I am asking is because I don't think that the same weight fabric in most other materials would swing in the same way as wool. For example, cotton twill doesn't seem to move in the same way as wool in about the same weight range. I don't think it is completely the weight that is causing this swing.

[Bugbear]

All right, I have done an experiment.

I took six strips of medium weight hair canvas, the kind you would put in the front of a suit jacket or need to use two layers of for a kilt, and taped them to the inside surface of six pleats on my acrylic kilt.

The strips are about eight inches long, and a little over an inch wide. Most of them taper to about a half inch, and they are only one layer. Basically scraps.

The stiffness of the hair canvas runs parallel to the folded edge of the pleat.
The edge of each strip is directly against the inside of the fold of the pleat.
The narrow end of the strips are toward the fell with the wide end very close to the bottom of the kilt.
A small piece of masking tape holds the top of the hair canvas strip to the inside of the pleat that is the outside face of the pleat.

All I can tell is that they seem to hang a little better, and have a little better feel to them. I have no good way of knowing if they swing better. I only wanted to see if I could put a slight influence on the outside surface of the fabric, and hair canvas was the only thing other than wool tartan that I had that passed the pinch test. Well... a fiberglass window screen kind of passed the pinch test.

By the way, I tried putting the hair canvas along the bottom edge with the stiffness running horizontally, but the pleat tended to curl outward.

Just something that popped into my mind, and I thought I would try. So for what it's worth...

Now I don't have to think about it anymore, ah.

[Bugbear]

I haven't gotten back to working on the acrylic kilt, I was working on the wool StillWater, but I did see some promising results with a strip of light weight hair canvas interfacing the pleats from the inside part of the fold. Just a strip of hair canvas, slightly wider than the pleat reviel, hanging there and attached at the top where the fell steeking would be.

I am guessing that the kilt would need to be lined or the hair canvas strips lined, at least. Also that a very loose stitch be put in the canvas to the pleat to keep it from moving too far out of place.

If the kilt were being hemmed a bit, it would take care of some of that I think, but the canvas strip has to be free to move a little. The pleat has to be able to float over the canvas a bit, though the canvas does grab the fabric just a little.

The hair canvas along the leading edge of the pleat seems to help the acrylic behave more like wool, so...