I like this forum as posting does make me think and the above about spoke length and tension has only ust revealed it self to me thanks to the CTC forum. I am glad that poster presented the maths behind it as I wouldn't have believed it otherwise. Having said that it is obvious as the crossing number effect bracing angle.
Me too! and I really appreciate your contributions.
The last rear I built was a Nemesis rim on a 32 hole Campy Chorus hub (the large axle silver version -- drool
) and based on the info below from http://spokeanwheel.110mb.com/lacingsr.htm#23
I laced 3x DS 2x NDS to improve the strength.
A mixed lacing pattern I discovered that works very well for balancing rear wheel lateral strengths is the 2-cross/3-cross lacing. This pattern uses 2-cross lacing on the non drive side and 3-cross lacing on the drive side. The non drive side spokes end up being shorter than the drive side spokes, a condition that causes theoretical force vector triangles that counteracts the dish offset of the wheel. This theoretical triangle is comprised of the real force vectors of the spokes and a theoretical force vector across the hub.
The figure to the right is a simplified version of the theoretical force vector triangles created by this lacing. The RED lines represent the force vectors of the spokes, and the BLUE line represents the force vector of the theoretical third side of the triangle. The location of a 3-cross length spoke on the non drive side is indicated by the GREEN spoke head for your reference. The PURPLE line, which is perpendicular to the BLUE force vector, indicates that the rim is closer to the non drive side of this theoretical force vector triangle.
Having a theoretical force vector triangle with the opposite circumstances of the actual triangles formed by drive and non drive spoke pairs works against the imbalance caused by the dish offset. A wheel built like this still has the drive side spokes under greater tension, but the difference in the tensions is not as great as they would be if the wheel was laced conventionally. Since the spoke tensions do not vary as much, the wheel has lateral strength characteristics that are more balanced than typical. It has been my experience that these wheels do hold true much better than conventionally laced (all 3-cross) multi-speed rear wheels.
From what you've said I'm now confused about doing this; as you wrote about 1x DS 3x NDS building more even tensions.
How does one think about DS/NDS tension vs bracing angle?