Custom-Length Spokes: Weaker?

wrote:
First, "improve the spoke line" as shown in "the Bicycle
Wheel" and if that doesn't help, get more and shorter spokes and
re-lace the wheel x1.

Yup... he is specifically talking about bending the spoke just above
the nipple, so the nipple ends up being more in-line with the hole.
Else you will have a bending load right at the spoke thread.

On Sat, 08 Nov 2008 14:56:29 -0800, Ron Ruff wrote:

wrote:
First, "improve the spoke line" as shown in "the Bicycle Wheel" and if
that doesn't help, get more and shorter spokes and re-lace the wheel
x1.

Yup... he is specifically talking about bending the spoke just above the
nipple, so the nipple ends up being more in-line with the hole. Else you
will have a bending load right at the spoke thread.

so how does bending the spoke remove the loading moment then?

jim beam wrote:

Ron Ruff wrote:

Jobst Brandt wrote:

First, "improve the spoke line" as shown in "the Bicycle Wheel" and if
that doesn't help, get more and shorter spokes and re-lace the wheel
x1.

Yup... he is specifically talking about bending the spoke just above the
nipple, so the nipple ends up being more in-line with the hole. Else you
will have a bending load right at the spoke thread.

so how does bending the spoke remove the loading moment then?

It doesn't. But it does move a lot of the resulting stress from the
threaded portion of the spoke to a smooth, full-diameter section.

Chalo

On Sat, 08 Nov 2008 15:23:11 -0800, Chalo wrote:

jim beam wrote:

Ron Ruff wrote:

Jobst Brandt wrote:

First, "improve the spoke line" as shown in "the Bicycle Wheel" and
if that doesn't help, get more and shorter spokes and re-lace the
wheel x1.

Yup... he is specifically talking about bending the spoke just above
the nipple, so the nipple ends up being more in-line with the hole.
Else you will have a bending load right at the spoke thread.

so how does bending the spoke remove the loading moment then?

It doesn't. But it does move a lot of the resulting stress from the
threaded portion of the spoke to a smooth, full-diameter section.


actually, it makes a single bending mode into a double - dependent on
angles and wire thickness. much better to make the rim get the spoke
angle right in the first place so there is /no/ bending.

In article
,
Chalo wrote:

Jay Taylor wrote:

Short spokes are more difficult to stress-relieve; ask the builder if he
did so. *I have many miles on short spokes I rolled, with no failures - but
I built a jig to stress-relieve them, as doing it by The Book demanded more
grip strength than I could manage.

If it were a residual stress problem, Pete would be breaking spokes at
the elbows. He says they are breaking at the nipples, thus it's
probably not a normal case of failure to stress-relieve at the time of
building.

Probably is. With short spokes it is particularly important
to have a fair lead from the rim to the the hub end of the
nipple. The nipples should sit squarely in the rim, and not
be pulled away from a fair lead by having to compensate for
the requirement that the spoke lead to a high flange.
This typically requires putting a bend in the spoke near the nipple.

--
Michael Press

jim beam wrote:
On Sat, 08 Nov 2008 15:23:11 -0800, Chalo wrote:

jim beam wrote:
Ron Ruff wrote:
Jobst Brandt wrote:
First, "improve the spoke line" as shown in "the Bicycle Wheel" and
if that doesn't help, get more and shorter spokes and re-lace the
wheel x1.
Yup... he is specifically talking about bending the spoke just above
the nipple, so the nipple ends up being more in-line with the hole.
Else you will have a bending load right at the spoke thread.
so how does bending the spoke remove the loading moment then?
It doesn't. But it does move a lot of the resulting stress from the
threaded portion of the spoke to a smooth, full-diameter section.


actually, it makes a single bending mode into a double - dependent on
angles and wire thickness. much better to make the rim get the spoke
angle right in the first place so there is /no/ bending.

What it does is eliminate the possibility for movement (flexing) in the
built wheel, movement being what causes fatigue.

Large flange hubs are always a problem - cross-1 might be insufficient
for a Rohloff because of spoke wind-up, and I think I'd go for cross-2
as a compromise. Better, get a rim and nipple combination that allows
the nipples to orient themselves better.

I've built a couple of Sturmey-Archer S-RF3 hubs into tiny 16" rims.
That gives an atrocious spoke/rim angle, even with the usual cross-2 non
interlaced pattern used by Brompton.

On Sun, 09 Nov 2008 06:11:49 +0000, Zog The Undeniable wrote:

jim beam wrote:
On Sat, 08 Nov 2008 15:23:11 -0800, Chalo wrote:

jim beam wrote:
Ron Ruff wrote:
Jobst Brandt wrote:
First, "improve the spoke line" as shown in "the Bicycle Wheel" and
if that doesn't help, get more and shorter spokes and re-lace the
wheel x1.
Yup... he is specifically talking about bending the spoke just above
the nipple, so the nipple ends up being more in-line with the hole.
Else you will have a bending load right at the spoke thread.
so how does bending the spoke remove the loading moment then?
It doesn't. But it does move a lot of the resulting stress from the
threaded portion of the spoke to a smooth, full-diameter section.


actually, it makes a single bending mode into a double - dependent on
angles and wire thickness. much better to make the rim get the spoke
angle right in the first place so there is /no/ bending.

What it does is eliminate the possibility for movement (flexing) in the
built wheel, movement being what causes fatigue.

Large flange hubs are always a problem - cross-1 might be insufficient
for a Rohloff because of spoke wind-up, and I think I'd go for cross-2
as a compromise. Better, get a rim and nipple combination that allows
the nipples to orient themselves better.

I've built a couple of Sturmey-Archer S-RF3 hubs into tiny 16" rims.
That gives an atrocious spoke/rim angle, even with the usual cross-2 non
interlaced pattern used by Brompton.

For the 16-inchers (305's) I am riding I drilled new holes at the correct
angles; I went with x1 on the rear and x3 on the front.

On Sun, 09 Nov 2008 06:11:49 +0000, Zog The Undeniable wrote:

On Sun, 09 Nov 2008 06:11:49 +0000, Zog The Undeniable wrote:

jim beam wrote:
On Sat, 08 Nov 2008 15:23:11 -0800, Chalo wrote:

jim beam wrote:
Ron Ruff wrote:
Jobst Brandt wrote:
First, "improve the spoke line" as shown in "the Bicycle Wheel" and
if that doesn't help, get more and shorter spokes and re-lace the
wheel x1.
Yup... he is specifically talking about bending the spoke just above
the nipple, so the nipple ends up being more in-line with the hole.
Else you will have a bending load right at the spoke thread.
so how does bending the spoke remove the loading moment then?
It doesn't. But it does move a lot of the resulting stress from the
threaded portion of the spoke to a smooth, full-diameter section.


actually, it makes a single bending mode into a double - dependent on
angles and wire thickness. much better to make the rim get the spoke
angle right in the first place so there is /no/ bending.

What it does is eliminate the possibility for movement (flexing) in the
built wheel, movement being what causes fatigue.

how does an indirect path with two kinks improve over an indirect path
with one kink? bending, and thus fatigue, is a direct result of indirect
path.



Large flange hubs are always a problem - cross-1 might be insufficient
for a Rohloff because of spoke wind-up,

spoke wind-up is not a function of spoke cross count.


and I think I'd go for cross-2
as a compromise.

1x is sufficient with a large hub like this.


Better, get a rim and nipple combination that allows
the nipples to orient themselves better.

indeed.



I've built a couple of Sturmey-Archer S-RF3 hubs into tiny 16" rims.
That gives an atrocious spoke/rim angle, even with the usual cross-2 non
interlaced pattern used by Brompton.

shoulda used 1x.

jim beam wrote:
actually, it makes a single bending mode into a double - dependent on
angles and wire thickness. much better to make the rim get the spoke
angle right in the first place so there is /no/ bending.

Well... that is difficult. And some of the lightest/strongest rims
have no offset in the drilling at all... ie holes are drilled right in
the plane of the rim rather than towards the hub flanges. Bending the
spoke above the nipple is something I do routinely, and I've yet to
see a problem with it.

On Sun, 09 Nov 2008 11:46:53 -0800, Ron Ruff wrote:

jim beam wrote:
actually, it makes a single bending mode into a double - dependent on
angles and wire thickness. much better to make the rim get the spoke
angle right in the first place so there is /no/ bending.

Well... that is difficult. And some of the lightest/strongest rims have
no offset in the drilling at all...

which rims are you looking at? i don't recall seeing a rim that's /ever/
had no spoke orientation offset. and by offset, i mean the exit angle,
not the location of the hole relative to the rim's circumferential plane.





ie holes are drilled right in the
plane of the rim rather than towards the hub flanges. Bending the spoke
above the nipple is something I do routinely, and I've yet to see a
problem with it.

anything offset from the axial load path is going to experience bending -
by definition.