Weisse Lift snipes anonymously:
>>>> It is indeed humorous that we squabble about these things.
>>>> But no, I don't think that the fellows who have posted that they
>>>> mark their spokes to observe twist are joking.
>>>> If spokes do indeed twist (everyone seems to agree that they do),
>>>> then a line drawn down the untwisted spoke ought to reveal it. I
>>>> haven't tried it (yet), but I expect that it's as much fun as
>>>> using a tensiometer.
>>>> Elsewhere, Jobst Brandt has mentioned attaching post-it markers
>>>> to spokes to demonstrate twist:
>>>> http://tinyurl.com/25l2c
>>>> In that post, "sued" is a truly unfortunate typo for "used."
>>> The post-it is a dynamic display of twist and not a means of
>>> untwisting spokes. If you think you can readily see a helix with
>>> a 1/8 to 1/4 twist on a spoke 300mm long then you have more acute
>>> eyesight than I. As I mentioned, lines on a barber pole make a
>>> full revolution on a large diameter with a helix angle of about 45
>>> degrees. Helix angle on a 300mm long spoke is less than one
>>> degree, sued or used.
>> Perhaps the people who like to draw lines on spokes have
>> sufficiently acute vision to notice that the line has moved at the
>> bottom 1/4 to 1/8 of a turn?
>> It's been suggested in this thread that a mark near the bottom is
>> enough to show the twist.
> On a well-lit work bench, I can clearly see the black Sharpie marker
> line on my spokes. I know Jobst doesn't use Revolution spokes so
> his 1/4-1/2 turn is valid for 14/15 or 15/16 spokes.
> I use Revolutions exclusively. And on the drive side rear, the
> Sharpie marking gives me 100% noise free truing, not that I have had
> to do it in a while. Drawing a thin, straight line on the spoke is
> easy. The felt tip has a larger diameter hub which I use to guide
> the side of the felt tip along the spoke. With light pressure and a
> new pen, the line is very thin, even on the 1.5 mm section. It only
> takes seconds to do the entire wheel from nip to crossing.
It is my experience that 1.5mm diameter spokes (Revolution) and 24 or
fewer spoke wheels with even 1.8mm diameter spoke shafts cannot be
adequately tightened without twisting off with a sharp crack and an
ejected crossbow like missile (the spoke end) flying through the air.
For this reason, I have unloaded the spoke to be adjusted by pulling
the rim toward the approach side of the spoke. In a wheel building
machine, this can be accomplished with a pneumatic actuator pressing
the rim inward to momentarily unload the spoke.
I don't see how you can get a wheel adequately tight without such
methods, spokes not withstanding the required torque even when well
lubricated. My experience with 1.5mm diameter spokes was with Berg
and Radaelli spokes and I shot a few of these into the ceiling. Hence
the warning in "the Bicycle Wheel" to not be in the line of fire when
tightening spokes. I built 24 spoke track wheels and had the same
experience with 1.8-1.6 conventional DT spokes.
> Alcohol removes the ink rapidly. I use Everclear but any C1-C3
> alcohol will work. I prefer Everclear because I know its not too
> terribly toxic, unless I drink it.
In any case, marking spokes is a tedious method of preventing residual
twist in spokes. A skilled hand can do the same easily and faster. I
explain, with diagram in "the Bicycle Wheel", how to feel twist with a
spoke wrench while adjusting a spoke.
Jobst Brandt
[email protected]
Making a thin black line is
