removing broken spoke nipples

  • Thread starter Bellsouth Ijit 2.0
  • Start date



On 2007-03-17, [email protected] <[email protected]> wrote:
> Ben C? writes:
>
>>>> Stress is tension per unit of cross-sectional area. In a
>>>> reasonably ideal world, total tension and average stress for the
>>>> whole wire are the same before and after stress relief, but the
>>>> distribution of stress throughout the cross section is what's
>>>> changed.

>
>>> distribution, yes.

>
>>>> If this is right, then if we talk about different regions of the
>>>> cross section carrying more or less of the tension, isn't that
>>>> saying the same thing?

>
>>> no. because a region has more local stress, doesn't mean it's
>>> bearing more of the applied load.

>
>>> the strain delta dictates load bearing and the strain delta is the
>>> same.

>
>> I think I get it: the key point here is that not all of the stress
>> comes from the load. Suppose you do have residual stresses from
>> forming, those give you localized regions of higher and lower
>> stresses inside the wire even when there's no external load on it at
>> all. Apply some load, and it doesn't follow that the higher stressed
>> regions are bearing more of that load. In fact it's probably borne
>> fairly evenly across the wire, although you've got details like the
>> fact that the nipple is gripping the spoke on its outside surface.

>
>> The applied stress is just superimposed on top of any stresses that
>> might already be there (from bits of the interior fighting each
>> other for example).

>
> What you say is based on the assumption that spoke tension increases
> in a wheel in use.


No, when I say "applied stress", I just mean applied by spoke tension.
 
On 2007-03-17, [email protected] <[email protected]> wrote:
> Ben C? writes:

[...]
>> Practically speaking if you have to re-tension after stress relief
>> you would be advised to stress relieve again.

>
> I think you should review what sort of yield stress relief causes.
> These are length changes of microns while the spoke as a whole is
> elastically stretched on the order of a millimeter, there is no
> practically measurable change in length or in tension in spokes from
> stress relieving.
>
> Your suggestion that spokes need re-tensioning after stress relief is
> misplaced.


It wasn't my suggestion! You haven't been following the thread closely,
although I don't blame you.
 
Carl Fogel writes:

>>> I think that's true, but if the re-increase is not uniform, but a
>>> bending stress, then we will bring the outside of the elbow
>>> straight back to yield, and we will be back to square one.


>>> Practically speaking if you have to re-tension after stress relief
>>> you would be advised to stress relieve again.


>> I think you should review what sort of yield stress relief causes.
>> These are length changes of microns while the spoke as a whole is
>> elastically stretched on the order of a millimeter, there is no
>> practically measurable change in length or in tension in spokes
>> from stress relieving. Your suggestion that spokes need
>> re-tensioning after stress relief is misplaced. Spokes do not sink
>> into the flanges further after tensioning when stress relieved
>> enough to affect tension. By that point in the wheel build they
>> have asymptotically reached home position.


> Squeezing spoke pairs together usually changes something enough to
> require small truing adjustments:


> "If, after stress relieving, the wheel is appreciably out of true in
> two smooth waves, then tension was too high, and retruing should
> begin by relaxing tension of all spokes half a turn. Usually, only
> small lateral corrections will be necessary after stress relieving."


> --"The Bicycle Wheel," 3rd edition, p. 106


I find that is a misinterpretation. The above citation explains what
occurs if spoke tension it too high, not what stress relieving does.
The issue at hand is whether spokes must be re-tensioned after stress
relieving. The above mentions retruing, not re-tensioning. Spokes do
not require re-tensioning!

So while you're at it, how about commenting on the nature of the
exchange taking place in this thread offered by "jb"? I ask because
you are so quick to find fault with content and tenor of my responses.
How does content and tone of those exchanges escape your critique?

Jobst Brandt
 
Ben C wrote:
> On 2007-03-17, jim beam <[email protected]> wrote:
>> Ben C wrote:

> [...]
>>> Stress is tension per unit of cross-sectional area. In a reasonably
>>> ideal world, total tension and average stress for the whole wire are the
>>> same before and after stress relief, but the distribution of stress
>>> throughout the cross section is what's changed.

>> distribution, yes.
>>
>>> If this is right, then if we talk about different regions of the cross
>>> section carrying more or less of the tension, isn't that saying the same
>>> thing?

>> no. because a region has more local stress, doesn't mean it's bearing
>> more of the applied load.
>>
>> the strain delta dictates load bearing and the strain delta is the
>> same.

>
> I think I get it: the key point here is that not all of the stress comes
> from the load. Suppose you do have residual stresses from forming, those
> give you localized regions of higher and lower stresses inside the wire
> even when there's no external load on it at all.


absolutely.

> Apply some load, and it
> doesn't follow that the higher stressed regions are bearing more of that
> load.


correct.

> In fact it's probably borne fairly evenly across the wire,


well, as a function of geometry, yes. bending vs. axial load, etc.

> although you've got details like the fact that the nipple is gripping
> the spoke on its outside surface.


that too.

>
> The applied stress is just superimposed on top of any stresses that
> might already be there (from bits of the interior fighting each other
> for example).


indeed.
 
Ben C wrote:
> On 2007-03-17, jim beam <[email protected]> wrote:
>> Ben C wrote:
>>> On 2007-03-17, Luns Tee <[email protected]> wrote:
>>> [...]
>>>> No, it's keeping things in the proper perspective. You were
>>>> claiming that stress increases back to where it started when you
>>>> increase tension back to what the structure needs. The tension lost
>>>> is the stress lost by yield times the sectional area of the yielded
>>>> material. Putting the tension back, tensile stress increases by this
>>>> same delta, divided by the sectional area of the entire spoke. Unless
>>>> the entire spoke yielded, this increase in stress is less than the
>>>> reduction from the yield.
>>> I think I've been missing something. Are you suggesting that after
>>> stress relief, the spoke tension is noticeably reduced a bit, and you
>>> need to give the spokes another 1/4 turn or so?
>>>
>>> This might be what jim beam meant by the "re-increase".

>> yes it is.
>>
>>> I didn't think it was necessary though-- stress relief causes almost
>>> immeasurably small deformation, so surely also only a very small change
>>> in tension?

>> tension change can be significant in the early stages - spokes bedding
>> into their hub holes is similar to brinell ball indentation.

>
> Not only that but in the early stages doing something like the Mavic
> method may also be changing the elbow bend angles which will drop the
> tension quite a bit.
>
> I should have made it clearer, but I thought we were talking about a
> final overload after full tensioning, just to yield the outside of the
> elbows in case they've ended up held close to yield stress by spoke
> tension.
>
>>> I take your point that even if you do re-tension after stress relief,
>>> the maximum stress over the cross-section should remain lower than it
>>> was before stress relief.

>> not if the applied stress is re-increased beck to original.

>
> If we're talking about bending stress at the elbow, then, yes,
> increasing spoke tension may bring the elbows back to yield. It might be
> harder this time around to reach yield though because bedding/bending
> might have reduced the moment on the elbow.
>
> My understanding of what Luns was saying is that if we had an uneven
> distribution of stress in the wire, which we evened out a bit by stress
> relief, then when we load the wire again tension will increase, but
> uniformly, resulting in lower peak regional stress for the same tension
> when we've finished.


if that's what he means, yes.

>
> I think that's true, but if the re-increase is not uniform, but a
> bending stress, then we will bring the outside of the elbow straight
> back to yield, and we will be back to square one.


which is why we see fatigue initiate at the point of highest applied
stress...

>
> Practically speaking if you have to retension after stress relief you
> would be advised to stress relieve again.


if there's no yielding, it's no longer doing anything.
 
[email protected] wrote:
> Ben C? writes:
>
>> Not only that but in the early stages doing something like the Mavic
>> method may also be changing the elbow bend angles which will drop
>> the tension quite a bit.

>
>> I should have made it clearer, but I thought we were talking about a
>> final overload after full tensioning, just to yield the outside of
>> the elbows in case they've ended up held close to yield stress by
>> spoke tension.

>
>>>> I take your point that even if you do re-tension after stress
>>>> relief, the maximum stress over the cross-section should remain
>>>> lower than it was before stress relief.

>
>>> not if the applied stress is re-increased beck to original.

>
>> If we're talking about bending stress at the elbow, then, yes,
>> increasing spoke tension may bring the elbows back to yield. It
>> might be harder this time around to reach yield though because
>> bedding/bending might have reduced the moment on the elbow.

>
>> My understanding of what Luns was saying is that if we had an uneven
>> distribution of stress in the wire, which we evened out a bit by
>> stress relief, then when we load the wire again tension will
>> increase, but uniformly, resulting in lower peak regional stress for
>> the same tension when we've finished.

>
>> I think that's true, but if the re-increase is not uniform, but a
>> bending stress, then we will bring the outside of the elbow straight
>> back to yield, and we will be back to square one.

>
>> Practically speaking if you have to re-tension after stress relief
>> you would be advised to stress relieve again.

>
> I think you should review what sort of yield stress relief causes.
> These are length changes of microns


really? you've measured? and if so, were you able to differentiate
"stress relief" yielding from fatigue load yielding? be very careful on
that one jobst - because you know about dislocations and fatigue crack
initiation, right?

> while the spoke as a whole is
> elastically stretched on the order of a millimeter, there is no
> practically measurable change in length or in tension in spokes from
> stress relieving.


you can't have it both ways jobst - you want yielding to support your
"stress relief" theory, but you want "no practically measurable change
in length or in tension". grasping at micron straws doesn't do it.
"trust me, it's causing stress relief. ignore the contradiction about
residual stress profiles and fatigue initiation, it's causing stress
relief".

>
> Your suggestion that spokes need re-tensioning after stress relief is
> misplaced. Spokes do not sink into the flanges further after
> tensioning when stress relieved enough to affect tension. By that
> point in the wheel build they have asymptotically reached home
> position.


spokes don't need re-tensioning after the "stress relief" [bedding in]
process is finished, but they sure do during it. /that/ is what's being
discussed.
 
[email protected] wrote:
> Ben C? writes:
>
>>>> Stress is tension per unit of cross-sectional area. In a
>>>> reasonably ideal world, total tension and average stress for the
>>>> whole wire are the same before and after stress relief, but the
>>>> distribution of stress throughout the cross section is what's
>>>> changed.

>
>>> distribution, yes.

>
>>>> If this is right, then if we talk about different regions of the
>>>> cross section carrying more or less of the tension, isn't that
>>>> saying the same thing?

>
>>> no. because a region has more local stress, doesn't mean it's
>>> bearing more of the applied load.

>
>>> the strain delta dictates load bearing and the strain delta is the
>>> same.

>
>> I think I get it: the key point here is that not all of the stress
>> comes from the load. Suppose you do have residual stresses from
>> forming, those give you localized regions of higher and lower
>> stresses inside the wire even when there's no external load on it at
>> all. Apply some load, and it doesn't follow that the higher stressed
>> regions are bearing more of that load. In fact it's probably borne
>> fairly evenly across the wire, although you've got details like the
>> fact that the nipple is gripping the spoke on its outside surface.

>
>> The applied stress is just superimposed on top of any stresses that
>> might already be there (from bits of the interior fighting each
>> other for example).

>
> What you say is based on the assumption that spoke tension increases
> in a wheel in use. Unless you are using too few spokes for a reliable
> wheel, spoke tension does not increase in a wheel enough to have any
> effect on residual stress. You can review the relative stresses in
> graphs and data in "the Bicycle Wheel" to reassure yourself of that.


[yawn.] so, tension doesn't increase enough to have an effect on
residual stress? yet we're expected to believe that residual stress
goes down to the micron level [where it would interact with dislocation
strain fields btw], /and/ we're to ignore residual stress distribution
profiles and observed fatigue initiation points??? i smell cattle
fodder - after use.
 
[email protected] wrote:
> Carl Fogel writes:
>
>>>> I think that's true, but if the re-increase is not uniform, but a
>>>> bending stress, then we will bring the outside of the elbow
>>>> straight back to yield, and we will be back to square one.

>
>>>> Practically speaking if you have to re-tension after stress relief
>>>> you would be advised to stress relieve again.

>
>>> I think you should review what sort of yield stress relief causes.
>>> These are length changes of microns while the spoke as a whole is
>>> elastically stretched on the order of a millimeter, there is no
>>> practically measurable change in length or in tension in spokes
>>> from stress relieving. Your suggestion that spokes need
>>> re-tensioning after stress relief is misplaced. Spokes do not sink
>>> into the flanges further after tensioning when stress relieved
>>> enough to affect tension. By that point in the wheel build they
>>> have asymptotically reached home position.

>
>> Squeezing spoke pairs together usually changes something enough to
>> require small truing adjustments:

>
>> "If, after stress relieving, the wheel is appreciably out of true in
>> two smooth waves, then tension was too high, and retruing should
>> begin by relaxing tension of all spokes half a turn. Usually, only
>> small lateral corrections will be necessary after stress relieving."

>
>> --"The Bicycle Wheel," 3rd edition, p. 106

>
> I find that is a misinterpretation. The above citation explains what
> occurs if spoke tension it too high, not what stress relieving does.
> The issue at hand is whether spokes must be re-tensioned after stress
> relieving. The above mentions retruing, not re-tensioning. Spokes do
> not require re-tensioning!
>
> So while you're at it, how about commenting on the nature of the
> exchange taking place in this thread offered by "jb"? I ask because
> you are so quick to find fault with content and tenor of my responses.
> How does content and tone of those exchanges escape your critique?


content jobst, content. /your/ tone is your defense when your content
is shown defective. /my/ tone is just naturally and consistently
offensive regardless of content.
 
On 17 Mar 2007 19:23:08 GMT, [email protected] wrote:

>Ben C? writes:
>
>> Not only that but in the early stages doing something like the Mavic
>> method may also be changing the elbow bend angles which will drop
>> the tension quite a bit.

>
>> I should have made it clearer, but I thought we were talking about a
>> final overload after full tensioning, just to yield the outside of
>> the elbows in case they've ended up held close to yield stress by
>> spoke tension.

>
>>>> I take your point that even if you do re-tension after stress
>>>> relief, the maximum stress over the cross-section should remain
>>>> lower than it was before stress relief.

>
>>> not if the applied stress is re-increased beck to original.

>
>> If we're talking about bending stress at the elbow, then, yes,
>> increasing spoke tension may bring the elbows back to yield. It
>> might be harder this time around to reach yield though because
>> bedding/bending might have reduced the moment on the elbow.

>
>> My understanding of what Luns was saying is that if we had an uneven
>> distribution of stress in the wire, which we evened out a bit by
>> stress relief, then when we load the wire again tension will
>> increase, but uniformly, resulting in lower peak regional stress for
>> the same tension when we've finished.

>
>> I think that's true, but if the re-increase is not uniform, but a
>> bending stress, then we will bring the outside of the elbow straight
>> back to yield, and we will be back to square one.

>
>> Practically speaking if you have to re-tension after stress relief
>> you would be advised to stress relieve again.

>
>I think you should review what sort of yield stress relief causes.
>These are length changes of microns while the spoke as a whole is
>elastically stretched on the order of a millimeter, there is no
>practically measurable change in length or in tension in spokes from
>stress relieving.
>
>Your suggestion that spokes need re-tensioning after stress relief is
>misplaced. Spokes do not sink into the flanges further after
>tensioning when stress relieved enough to affect tension. By that
>point in the wheel build they have asymptotically reached home
>position.
>
>Jobst Brandt


Dear Jobst,

Squeezing spoke pairs together usually changes something enough to
require small truing adjustments:

"If, after stress relieving, the wheel is appreciably out of true in
two smooth waves, then tension was too high, and retruing should begin
by relaxing tension of all spokes half a turn. Usually, only small
lateral corrections will be necessary after stress relieving."

--"The Bicycle Wheel," 3rd edition, p. 106

Cheers,

Carl Fogel
 
In article <[email protected]>,
Ben C <[email protected]> wrote:
>On 2007-03-17, Luns Tee <[email protected]> wrote:
>[...]
>> No, it's keeping things in the proper perspective. You were
>> claiming that stress increases back to where it started when you
>> increase tension back to what the structure needs. The tension lost
>> is the stress lost by yield times the sectional area of the yielded
>> material. Putting the tension back, tensile stress increases by this
>> same delta, divided by the sectional area of the entire spoke. Unless
>> the entire spoke yielded, this increase in stress is less than the
>> reduction from the yield.

>
>I think I've been missing something. Are you suggesting that after
>stress relief, the spoke tension is noticeably reduced a bit, and you
>need to give the spokes another 1/4 turn or so?


Reduced, but not noticably. I said 'small' but jb seemed to have
an issue with that, so I chose to humour him anyway and carry things
through as though it were more significant than that.

>This might be what jim beam meant by the "re-increase".
>
>I didn't think it was necessary though-- stress relief causes almost
>immeasurably small deformation, so surely also only a very small change
>in tension?


It isn't - you had the right picture.

>I take your point that even if you do re-tension after stress relief,
>the maximum stress over the cross-section should remain lower than it
>was before stress relief.


Thanks; I'm glad someone gets it.

-Luns
 
Carl Fogel writes:

>>>>> I think that's true, but if the re-increase is not uniform, but
>>>>> a bending stress, then we will bring the outside of the elbow
>>>>> straight back to yield, and we will be back to square one.


>>>>> Practically speaking if you have to re-tension after stress
>>>>> relief you would be advised to stress relieve again.


>>>> I think you should review what sort of yield stress relief
>>>> causes. These are length changes of microns while the spoke as a
>>>> whole is elastically stretched on the order of a millimeter,
>>>> there is no practically measurable change in length or in tension
>>>> in spokes from stress relieving. Your suggestion that spokes
>>>> need re-tensioning after stress relief is misplaced. Spokes do
>>>> not sink into the flanges further after tensioning when stress
>>>> relieved enough to affect tension. By that point in the wheel
>>>> build they have asymptotically reached home position.


>>> Squeezing spoke pairs together usually changes something enough to
>>> require small truing adjustments:


>>> "If, after stress relieving, the wheel is appreciably out of true
>>> in two smooth waves, then tension was too high, and retruing
>>> should begin by relaxing tension of all spokes half a
>>> turn. Usually, only small lateral corrections will be necessary
>>> after stress relieving."


>>> --"The Bicycle Wheel," 3rd edition, p. 106


>> I find that is a misinterpretation. The above citation explains
>> what occurs if spoke tension it too high, not what stress relieving
>> does. The issue at hand is whether spokes must be re-tensioned
>> after stress relieving. The above mentions retruing, not
>> re-tensioning. Spokes do not require re-tensioning!


>> So while you're at it, how about commenting on the nature of the
>> exchange taking place in this thread offered by "jb"? I ask
>> because you are so quick to find fault with content and tenor of my
>> responses. How does content and tone of those exchanges escape
>> your critique?


> "Usually, only small lateral corrections will be necessary after
> stress relieving."


> What is the difference between turning a spoke nipple to laterally
> true a rim and turning a spoke nipple to change the spoke tension?


One is adding tension the other is truing the wheel, which in this
case is loosening and tightening appropriate spokes, in contrast to
restoring lost tension to the wheel.

So what do you have to offer about the rude epithets appearing on this
thread? I hear sounds of silence.

Jobst Brandt
 
On 2007-03-17, [email protected] <[email protected]> wrote:
> On 17 Mar 2007 20:04:39 GMT, [email protected] wrote:
>
>>Carl Fogel writes:

[...]
>>> Squeezing spoke pairs together usually changes something enough to
>>> require small truing adjustments:

>>
>>> "If, after stress relieving, the wheel is appreciably out of true in
>>> two smooth waves, then tension was too high, and retruing should
>>> begin by relaxing tension of all spokes half a turn. Usually, only
>>> small lateral corrections will be necessary after stress relieving."

>>
>>> --"The Bicycle Wheel," 3rd edition, p. 106

>>
>>I find that is a misinterpretation. The above citation explains what
>>occurs if spoke tension it too high, not what stress relieving does.
>>The issue at hand is whether spokes must be re-tensioned after stress
>>relieving. The above mentions retruing, not re-tensioning. Spokes do
>>not require re-tensioning!

[...]
> Dear Jobst,
>
> "Usually, only small lateral corrections will be necessary after
> stress relieving."
>
> What is the difference between turning a spoke nipple to laterally
> true a rim and turning a spoke nipple to change the spoke tension?


The difference is in the intention. In one case you adjust one or two
spokes to make the wheel true; in the other you adjust them all to
change the wheel's tension.

We still make distinctions between radial truing, lateral truing,
tensioning and dishing, even though they all consist of turning the
nipples.

(Conversely, bashing the wheel on a tree-trunk, walking on it, squeezing
it, leaning on it and mangling it with a crowbar are all called the same
thing: "stress-relief").

If stress-relief reduced whole-spoke tension significantly you'd expect
to have to tighten up all the spokes by a bit to compensate, since you
have stress-relieved all of them. That it may affect the tension of one
or two enough to require a bit of re-truing just reflects the fact that
nothing's perfect.
 
On 17 Mar 2007 20:04:39 GMT, [email protected] wrote:

>Carl Fogel writes:
>
>>>> I think that's true, but if the re-increase is not uniform, but a
>>>> bending stress, then we will bring the outside of the elbow
>>>> straight back to yield, and we will be back to square one.

>
>>>> Practically speaking if you have to re-tension after stress relief
>>>> you would be advised to stress relieve again.

>
>>> I think you should review what sort of yield stress relief causes.
>>> These are length changes of microns while the spoke as a whole is
>>> elastically stretched on the order of a millimeter, there is no
>>> practically measurable change in length or in tension in spokes
>>> from stress relieving. Your suggestion that spokes need
>>> re-tensioning after stress relief is misplaced. Spokes do not sink
>>> into the flanges further after tensioning when stress relieved
>>> enough to affect tension. By that point in the wheel build they
>>> have asymptotically reached home position.

>
>> Squeezing spoke pairs together usually changes something enough to
>> require small truing adjustments:

>
>> "If, after stress relieving, the wheel is appreciably out of true in
>> two smooth waves, then tension was too high, and retruing should
>> begin by relaxing tension of all spokes half a turn. Usually, only
>> small lateral corrections will be necessary after stress relieving."

>
>> --"The Bicycle Wheel," 3rd edition, p. 106

>
>I find that is a misinterpretation. The above citation explains what
>occurs if spoke tension it too high, not what stress relieving does.
>The issue at hand is whether spokes must be re-tensioned after stress
>relieving. The above mentions retruing, not re-tensioning. Spokes do
>not require re-tensioning!
>
>So while you're at it, how about commenting on the nature of the
>exchange taking place in this thread offered by "jb"? I ask because
>you are so quick to find fault with content and tenor of my responses.
>How does content and tone of those exchanges escape your critique?
>
>Jobst Brandt


Dear Jobst,

"Usually, only small lateral corrections will be necessary after
stress relieving."

What is the difference between turning a spoke nipple to laterally
true a rim and turning a spoke nipple to change the spoke tension?

Cheers,

Carl Fogel
 
well, i offer the teflon wax lube for the rear hub during and right
after assembly to solve problems suffered wheels built by group two
builders. Including the wax lube as standard instruction in the
STANDARD INSTRUCTIONS shall promote wheel building.

as for the other missleani: (**&*^!!@#%$# is good for the lungs,
develops persona, relieves tension but not if thrust upon an
individual or group such as ...
 
in group two:
the wheel radii vary following stress relief-1/4 turn is not unusually
hi.
does increased spoke breaking tension then occur
yep! generic spokes do not spring back after the first road test, a
few are permanently bent.
and *&^%&^$$$ 2-3 of the little 8&^%^%##$3 could fail at the hub
during the second road test.
i assume that happens to DT only less frequently.
 
In article <[email protected]>,
jim beam <[email protected]> wrote:

> Tim McNamara wrote:
> > In article <[email protected]>,
> > jim beam <[email protected]> wrote:
> >
> > Oh, dear. There you go again. Your standard practice is to
> > distort what others say, and then to refute the distorted version
> > rather than what the person actually wrote, and then you persuade
> > yourself that you've won the argument. It's called a straw man
> > fallacy, which you use so much that you had best stay away from
> > open flames.
> >
> > This is what makes you a liar and a fraud, by the way. It's sad,
> > because you might be right about stuff. But you are so focused on
> > taking down Jobst (and also Krygowski and Annan) that you fail to
> > contribute meaningfully to the discussions. Instead of providing
> > useful information, you merely aim to discredit.

>
> i present facts. the facts peak for themselves.


Few facts, jim. You frequently present supposition and opinion that you
have conflated with facts. And when the fact that you have the wrong
end of the stick is pointed out to you, you become rude, arrogant and
insulting.

> i contest ********.


You certainly spout enough of it.

> and brown nosing.


LOL.

> > Ethical and knowledgeable contributors use their knowledge to help
> > explain things and make it understandable to others, You use yours
> > as a club to demean others. Your participation here has nothing to
> > do with advancing the collective understanding and everything to do
> > with your bitterness and your ego trip.
> >
> >> you're insane if you think your inability to study and understand
> >> math and engineering principles give you the ability to write ****
> >> like that.

> >
> > I am quite aware that my knowledge of engineering is minimal, jim.

>
> no ****. but it sure doesn't stop you expressing underinformed
> opinion!
>
> > That's why I appreciate engineers who can write in plain English-
> > after all, as Feynmann pointed out, "if you can't explain it in
> > plain English you don't understand it yourself."

>
> that's ******** you sycophantic brown nose. by your twisted logic,
> jobst writing "in plain english" [and quoting feynmann] that bearings
> don't brinell is acceptable [to pick just one example], even when
> it's fact that they do.


I didn't mention Jobst. Jobst's writing is often not in very plain
English, in fact.

> utter ****-sucking ********.


You are merely vulgar now.

> > Fortunately there are plain language
> > descriptions of most engineering principles that are easily found
> > on the Internets using the Google, so I can fill in some of the
> > gaps in my understanding when they present themselves. I also
> > appreciate the engineers who provide ways to check things out at
> > home in a simple and straightforward manner- something I don't
> > recall you ever doing.

>
> no, you get bamboozled by ******** because you don't know any
> different.
> and worse, you defend your ignorance!


Perhaps you just don't get the fact that it is your arguments that fail
to be compelling time and time and time again. Part of that is simply
due to the fact that you waste so much time and energy on character
assassination. You appear to be little interested in improving the
quality of the discussion, and highly motivated by self-aggrandizement
(which is humorous in that you hide your identity...).

> >> your b.s. about "ejection" force exceeding retention force was a
> >> peach, especially when you kept on repeating it. but your
> >> subsequent howlers about iso standards being "regulations" and
> >> minimums being maximums -

> >
> > More of your distortions and lies. First, I was talking about CPSC
> > regulations not ISO standards, and I made that very clear in the
> > context (identifying them specifically as CPSC regulations and
> > providing the link to the regulations themselves).

>
> really? you cited cpsc linkage? funny, my news reader seems to have
> edited that out. and annan doesn't cite cpsc, he quotes iso.


Yup. I quoted the text of the CPSC regulations. Provided the link too.
Also noted that the CPSC intended to increase the pullout force
resistance, too.

> > Second, I never confused minimums
> > and maximums; you did that in at attempt to discredit and obfuscate
> > when it was clear that the facts didn't back up your position. You
> > will never win by lying. Haven't you learned that by now?

>
> ********.


What's "********?" You think you *can* win by lying? Rovianism may
work in politics, it has no hope in science.

> "Those regulations set a minimum standard for the maximum practical
> clamping force that can be achieved with the skewer."
>
> there's nothing maximal about a minimal standard.


Isn't it interesting that I can't find the post in the Google archives
where I supposedly wrote that. Do you have a specific citation for it?

> >> well dude, you do ahead and shroud your fragile little mind in all
> >> kinds of excuse, but the fact is, you're not qualified to endorse
> >> the use of toilet paper, let alone anything with numbers attached
> >> to it.

> >
> > Back to base ad hominem and invective, evidence again of the
> > weakness of your position and your logical armamentarium. And
> > perhaps also evidence of some some things about your personality
> > and character as well.
> >
> >> you're utterly innumerate.

> >
> > Not utterly, no.

>
> really? so is 1600N > 5000N?


Nope. But you can't guarantee that the right side of that expression is
5000N. That's the part you kept dancing around. Your entire position
is posited on the assumption- rather than a fact- that the right side of
the equation is necessarily higher than the left side. It's a
foundation of sand.

> > I can do arithmetic, basic algebra and have a good
> > understanding of statistics (since that applies directly to my
> > field of science, it was required in graduate school). I have
> > never had a need to learn advanced mathematics so I can't do that
> > stuff, and as a result can't always follow Luns's math. From what
> > you've posted it looks like you can't follow it either. In fact,
> > come to think of it, your participation pretty much disappears when
> > the heavy math comes out. What's up with that? Perhaps you are
> > not as numerate as you pretend.

>
> yeah, i'm a real dumb-ass. and a photo fraud. and you're real
> useful with all those fine technical contributions you make. go back
> to the bedroom brown-nose. your master awaits.


Again you're just being sad and pathetic. It's like being in an
argument with a 12 year old.
 

> What is the difference between turning a spoke nipple to laterally
> true a rim and turning a spoke nipple to change the spoke tension?


oooh. that's an easy one. IF ( capital if ) the new wheel tune is
adequate at least into group two then stress relief: mavic, sierra,
rodal, brown parsec1, Jobst Brandt, or sissy method- will give a
laterally out of shape rim of less tension in relieved areas. one
would then turn a nipple to bring the rim back into line but in theory
if not inpractice off course, the tension AS THE RIM GOES BACK INTO
LINE, the tension returns ( sorry )
to "normal" as a math construct.
there may be value in thinking of the real wheel and the math/
engineered simultaneously as one tunes a new or retunes a battered
wheel.
 
On 17 Mar 2007 21:31:09 GMT, [email protected] wrote:

>Carl Fogel writes:
>
>>>>>> I think that's true, but if the re-increase is not uniform, but
>>>>>> a bending stress, then we will bring the outside of the elbow
>>>>>> straight back to yield, and we will be back to square one.

>
>>>>>> Practically speaking if you have to re-tension after stress
>>>>>> relief you would be advised to stress relieve again.

>
>>>>> I think you should review what sort of yield stress relief
>>>>> causes. These are length changes of microns while the spoke as a
>>>>> whole is elastically stretched on the order of a millimeter,
>>>>> there is no practically measurable change in length or in tension
>>>>> in spokes from stress relieving. Your suggestion that spokes
>>>>> need re-tensioning after stress relief is misplaced. Spokes do
>>>>> not sink into the flanges further after tensioning when stress
>>>>> relieved enough to affect tension. By that point in the wheel
>>>>> build they have asymptotically reached home position.

>
>>>> Squeezing spoke pairs together usually changes something enough to
>>>> require small truing adjustments:

>
>>>> "If, after stress relieving, the wheel is appreciably out of true
>>>> in two smooth waves, then tension was too high, and retruing
>>>> should begin by relaxing tension of all spokes half a
>>>> turn. Usually, only small lateral corrections will be necessary
>>>> after stress relieving."

>
>>>> --"The Bicycle Wheel," 3rd edition, p. 106

>
>>> I find that is a misinterpretation. The above citation explains
>>> what occurs if spoke tension it too high, not what stress relieving
>>> does. The issue at hand is whether spokes must be re-tensioned
>>> after stress relieving. The above mentions retruing, not
>>> re-tensioning. Spokes do not require re-tensioning!

>
>>> So while you're at it, how about commenting on the nature of the
>>> exchange taking place in this thread offered by "jb"? I ask
>>> because you are so quick to find fault with content and tenor of my
>>> responses. How does content and tone of those exchanges escape
>>> your critique?

>
>> "Usually, only small lateral corrections will be necessary after
>> stress relieving."

>
>> What is the difference between turning a spoke nipple to laterally
>> true a rim and turning a spoke nipple to change the spoke tension?

>
>One is adding tension the other is truing the wheel, which in this
>case is loosening and tightening appropriate spokes, in contrast to
>restoring lost tension to the wheel.
>
>So what do you have to offer about the rude epithets appearing on this
>thread? I hear sounds of silence.
>
>Jobst Brandt


Dear Jobst,

Why do sections of the rim move to new lateral positions when spokes
are squeezed?

As for my silence, consider how tactful it was and how foolish it is
to keep whining about this:

http://groups.google.com/group/rec.bicycles.tech/msg/530db1a52761ea77

Or this:

http://groups.google.com/group/rec.bicycles.tech/msg/3888013418502011

I understand that it rankles to have your bad manners pointed out on
the newsgroup, but waving your arms and pointing at the other children
only draws attention to something everyone else was willing to drop.

Feel free to write directly to Jim Beam, just as I wrote directly to
you. I doubt that it will do any good, since he and Tim McNamara are
engrossed in their familiar squabble.

Cheers,

Carl Fogel
 

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