Originally Posted by
dabac
The rim doesn't care much about where the spokes are anchored at that stage - unless he's bringing some spokes to tension way before the others by giving all nipples equal turns and a flawed lace pattern has left him with some spokes effectively shorter than the others. But lacing with wrong spoke lengths like that usually only means that the wheel goes out of true. To get (residual) tacoing you've got to have overtension or an outer force.
An asymmetrical wheel is one where the spokes for either trailing or leading spokes are all fed from the same side. Old machine built wheels were done this way since the machine wasn't sophisticated enough to feed spokes from either side. It's a common newbie mistake also. It results in a wheel that has uneven tension...much like using two different length spokes...that is prone to tacoing.
Originally Posted by
dabac
How would you get that to work? Spoke holes are "always" offset from one flange to the other. Go through any spoke hole parallell with the axle and you end up smack in the middle between two spoke holes on the other side. Either they're always facign each other or they're never facing each other, for any X pattern.
You are being too literal. Take two spokes that are on opposite sides of the wheel but are doing the same job, i.e. both are trailing or leading. They should be mirror images of each other. If one head faces in, the other side will also face inward. If the head of one faces outward, so will the other. For example
If the spokes aren't like this but instead have the heads facing in the same direction, you can end up with an unstable structure since the forces on the heads are pulling the wheel towards one side. Put a little sideways force on it and the wheel will settle into a nice low energy state that looks like a potato chip
It was very common in the 70s and 80s to have this happen. That's part of the reason I started building my own wheels.