Originally Posted by
Darth Lefty
I watched a video a while back about a wheel truing machine, made in Denmark, I think. It took a loosely assembled wheel and it does all the things - all of them! - that a human would, in pretty much the same way. Turning the wheel to feel for high or low spots and adjusting, unwinding, squeezing spokes, etc. except I wasn't clear if maybe that it worked by feeling torque on the nipple rather than measuring spoke tension. The nipples were turned from the channel of the rim with a driver, not at the flats with a wrench. Which conceptually should work pretty well for a human too if he had such a tool. It was clear to me that the only thing limiting such a machine is how much time you gave it to work, and that if you gave it enough time, it could absolutely be better than anything a human could do.
I was sort of surprised by that. There are clear limits on the approach - how fast can you turn it and grab a spoke nipple without marring it? Knowing nothing before watching, I imagined it would take some different, faster approach, - like maybe clamping down wheel and hub very hard, and doing them all at once with a motor on each spoke to the same torque.
Sounds good in theory, but not in the real world.
If a human measures the tension, a human can adjust the tension.
I've yet to run into a wheel that would have "perfect tension" AND "perfect true".
Rims aren't perfect, even high quality ones, although they tend to be less bad.
As a test, just take your caliper and run it around the entire rim to measure the outside width. On the rim I mentioned in my other post, the difference between widest/narrowest was .035". That's nearly 1mm.
A human will "see" that, whereas a machine likely doesn't.
Often, when building a wheel, you have to fudge a bit between even tension and perfect true. One has to decide how much to compromise to make the "best" wheel overall, with the parts you have.