Hello everyone, I've been searching for a solution to a rather vexing problem for a while now, (vexing because I'm just a simple-minded redneck boatbuilder) and since it looks like a mathematical problem to me, perhaps someone here could help me make sense of it. (Wich unfortunately requires making sense of my writing, most likely the greater obstacle) A little background; I'm investigating a novel technique to manufacture composite tubing, specifically, using a hollow braid under tension as a method of compacting a composite laminate during it's cure. But what I can't figure out is how the tension of the braid correlates to the amount of "squeeze" exerted on the laminate. A hollow braid has an even number of strands, half of wich forms a right-hand helix, and the other half forms a left-hand helix, the righties and lefties are also interlaced to keep the braid from falling apart. It's the same thing as the classic "chinese finger-trap" i.e, when you stretch it out, its diameter contracts, and when you push it together the diameter expands. So, by taking a length of the braid and slipping a mandrel (a straight piece of aluminium tubing in this case) into it and pulling on its ends, the braid should cinch down on the mandrel. Since the force of the cinching action is expressed as pressure per unit area, it seems like I'll need the total area of the mandrel in the calculation. But beyond that I'm stuck, do I then base it on the curvature (radius?) the strands describe going through the helix? Or do I try to figure it out based on the angle between mandrel and strands somehow? Help, I'm way out of my comfort-zone here! Yoke. P.S. The braid consists of dry carbon (graphite) fibers and is as soft and flexible as any other textile fabric before it's processed with epoxy resin. P.P.S. Stretch of the fibers should be too small to matter, and I have some tricks to deal with the friction issues.