Wheelbuild question(s)

[Jonesy]

Materials:

XT M756 disk hubs, front and rear.
Mavic X618 26" rims, front and rear.
DT Competition 14/15/14 spokes/brass nipples (indeterminant length, as
we will see.)
32-hole, 3x.
The Book.
Gerd Shraner's version.
Sheldon's wheelbuild stuff, printed.
Barnett's Manual.

Two different sources put the ERD of these rims at 541mm. I get spoke
lengths calculated thusly:

LF, 259.9mm
RF, 261.0mm
LR, 261.0mm
RR, 259.7mm

I have read here and in Jobst's book (IIRC) that swaged spokes stretch
about 0.5mm at the proper tension, and that the rim likewise
"compresses" about the same amount. Since I have never build wheels
with swaged spokes before, I want to make sure I order the proper
length spokes (and nipples, if that's a concern.)

If I use regular, DT 12mm 14ga. nipples, does that work OK with this
rim? In addition, the spokes only come in even lengths (as far as I
can find), so I am guessing that I need half to be 258, and the other
260, and that some (~1mm) of thread will be exposed on the LF and RR.

IOW, I am thinking that I need 32 258mm spokes and 32 260mm spokes. I
would not wish to buy the wrong lengths, so I am imploring the experts
to review my calculations before I open my wallet, or get them laced
up.

Thank you very much (and for the opportunity to talk about technical
issues surrounding bicycles, rather than the American political system
and it's players.)
--
Robert F. Jones

 

[jim beam]

Jonesy wrote:

> Materials:
>
> XT M756 disk hubs, front and rear.
> Mavic X618 26" rims, front and rear.
> DT Competition 14/15/14 spokes/brass nipples (indeterminant length, as
> we will see.)
> 32-hole, 3x.
> The Book.
> Gerd Shraner's version.
> Sheldon's wheelbuild stuff, printed.
> Barnett's Manual.
>
> Two different sources put the ERD of these rims at 541mm. I get spoke
> lengths calculated thusly:
>
> LF, 259.9mm
> RF, 261.0mm
> LR, 261.0mm
> RR, 259.7mm
>
> I have read here and in Jobst's book (IIRC) that swaged spokes stretch
> about 0.5mm at the proper tension, and that the rim likewise
> "compresses" about the same amount. Since I have never build wheels
> with swaged spokes before, I want to make sure I order the proper
> length spokes (and nipples, if that's a concern.)

spoke length is not ultra-critical. nearest mm is more than good
enough. the fact that manufacturers supply spokes in only 2mm
increments ought to give you some comfort in this regard.

one comment: "swaged" is a specific term for just one spoke manufacture
process - the hammering process used by d.t. the correct generic
product term is "butted" because that includes the other processes used
like drawing [sapim] & grinding [wheelsmith].

>
> If I use regular, DT 12mm 14ga. nipples, does that work OK with this
> rim? In addition, the spokes only come in even lengths (as far as I
> can find), so I am guessing that I need half to be 258, and the other
> 260, and that some (~1mm) of thread will be exposed on the LF and RR.

nipps are fine. no, if you have the correct lengths, you won't have any
thread showing - nor should you. if you want to check your calcs,
excelsports.com have a spoke length list you can use. so does d.t.'s
web site.

>
> IOW, I am thinking that I need 32 258mm spokes and 32 260mm spokes. I
> would not wish to buy the wrong lengths, so I am imploring the experts
> to review my calculations before I open my wallet, or get them laced
> up.
>
> Thank you very much (and for the opportunity to talk about technical
> issues surrounding bicycles, rather than the American political system
> and it's players.)

 

[Jonesy]

jim beam <[email protected]> wrote in message news:<v4lEc.1138$%[email protected]>...
> Jonesy wrote:
>
> > Materials:
> >
> > XT M756 disk hubs, front and rear.
> > Mavic X618 26" rims, front and rear.
> > DT Competition 14/15/14 spokes/brass nipples (indeterminant length, as
> > we will see.)
> > 32-hole, 3x.
> > The Book.
> > Gerd Shraner's version.
> > Sheldon's wheelbuild stuff, printed.
> > Barnett's Manual.
> >
> > Two different sources put the ERD of these rims at 541mm. I get spoke
> > lengths calculated thusly:
> >
> > LF, 259.9mm
> > RF, 261.0mm
> > LR, 261.0mm
> > RR, 259.7mm
> >
> > I have read here and in Jobst's book (IIRC) that swaged spokes stretch
> > about 0.5mm at the proper tension, and that the rim likewise
> > "compresses" about the same amount. Since I have never build wheels
> > with swaged spokes before, I want to make sure I order the proper
> > length spokes (and nipples, if that's a concern.)
>
> spoke length is not ultra-critical. nearest mm is more than good
> enough. the fact that manufacturers supply spokes in only 2mm
> increments ought to give you some comfort in this regard.

From my previous wheelbuilds, I had that idea in mind. Never having
used disk brake hubs nor swaged spokes before, I felt that I should
ask before ordering the wrong size.

> one comment: "swaged" is a specific term for just one spoke manufacture
> process - the hammering process used by d.t. the correct generic
> product term is "butted" because that includes the other processes used
> like drawing [sapim] & grinding [wheelsmith].

I'm not sure that drawing and butting are the same. And grinding is
none of the three!

> > If I use regular, DT 12mm 14ga. nipples, does that work OK with this
> > rim? In addition, the spokes only come in even lengths (as far as I
> > can find), so I am guessing that I need half to be 258, and the other
> > 260, and that some (~1mm) of thread will be exposed on the LF and RR.
>
> nipps are fine. no, if you have the correct lengths, you won't have any
> thread showing - nor should you. if you want to check your calcs,
> excelsports.com have a spoke length list you can use. so does d.t.'s
> web site.

I have checked a couple of different places, but another surely won't
hurt. Mostly, I wanted verifcation of my above numbers as a "reality
check," such that I buy properly the first time.

> > IOW, I am thinking that I need 32 258mm spokes and 32 260mm spokes. I
> > would not wish to buy the wrong lengths, so I am imploring the experts
> > to review my calculations before I open my wallet, or get them laced
> > up.

Thanks, Jim,
--
R.F. Jones

 

[Sheldon Brown]

jim beam wrote:

>>one comment: "swaged" is a specific term for just one spoke manufacture
>>process - the hammering process used by d.t. the correct generic
>>product term is "butted" because that includes the other processes used
>>like drawing [sapim] & grinding [wheelsmith].
>
R.F. Jones replied:
>
> I'm not sure that drawing and butting are the same. And grinding is
> none of the three!

"Butting" is not a specific process. It can refer to any means of
producing a butted (thicker on one or both ends) part.

Swaging is cold working, generally done by impact. Strictly speaking,
all spokes are swaged, 'cause that's how the heads are made.

Drawing is stretching past the yield point, and I believe it's commonly
done between rollers. This is how all wire products are made.

Sheldon "Semantics" Brown
Newtonville, Massachusetts
+-----------------------------------------+
| Man invented language to satisfy his |
| deep need to complain. -- Lily Tomlin |
+-----------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

 

[jim beam]

Jonesy wrote:

> jim beam <[email protected]> wrote in message news:<v4lEc.1138$%[email protected]>...
>
>>Jonesy wrote:
>>
>>
>>>Materials:
>>>
>>>XT M756 disk hubs, front and rear.
>>>Mavic X618 26" rims, front and rear.
>>>DT Competition 14/15/14 spokes/brass nipples (indeterminant length, as
>>>we will see.)
>>>32-hole, 3x.
>>>The Book.
>>>Gerd Shraner's version.
>>>Sheldon's wheelbuild stuff, printed.
>>>Barnett's Manual.
>>>
>>>Two different sources put the ERD of these rims at 541mm. I get spoke
>>>lengths calculated thusly:
>>>
>>>LF, 259.9mm
>>>RF, 261.0mm
>>>LR, 261.0mm
>>>RR, 259.7mm
>>>
>>>I have read here and in Jobst's book (IIRC) that swaged spokes stretch
>>>about 0.5mm at the proper tension, and that the rim likewise
>>>"compresses" about the same amount. Since I have never build wheels
>>>with swaged spokes before, I want to make sure I order the proper
>>>length spokes (and nipples, if that's a concern.)
>>
>>spoke length is not ultra-critical. nearest mm is more than good
>>enough. the fact that manufacturers supply spokes in only 2mm
>>increments ought to give you some comfort in this regard.
>
>
> From my previous wheelbuilds, I had that idea in mind. Never having
> used disk brake hubs nor swaged spokes before, I felt that I should
> ask before ordering the wrong size.
>
>
>>one comment: "swaged" is a specific term for just one spoke manufacture
>>process - the hammering process used by d.t. the correct generic
>>product term is "butted" because that includes the other processes used
>>like drawing [sapim] & grinding [wheelsmith].
>
>
> I'm not sure that drawing and butting are the same. And grinding is
> none of the three!

drawing achieves butting, as does grinding. butting in this instance is
simply reducing the mid-span spoke diameter. and there's basically 3
production methods - these are:

1. hammering the spoke to a smaller diameter
2. drawing it through a die to reduce the diameter, or
3. grinding the surface material away to reduce the diameter.

these are separately used in d.t., sapim & wheelsmith spokes
respectively. all 3 methods produce effectively the same product, but
only one of these can be referred to as "swaging", the process used by
d.t. hence "butted" spokes, it is the proper term to use.

>
>
>>>If I use regular, DT 12mm 14ga. nipples, does that work OK with this
>>>rim? In addition, the spokes only come in even lengths (as far as I
>>>can find), so I am guessing that I need half to be 258, and the other
>>>260, and that some (~1mm) of thread will be exposed on the LF and RR.
>>
>>nipps are fine. no, if you have the correct lengths, you won't have any
>>thread showing - nor should you. if you want to check your calcs,
>>excelsports.com have a spoke length list you can use. so does d.t.'s
>>web site.
>
>
> I have checked a couple of different places, but another surely won't
> hurt. Mostly, I wanted verifcation of my above numbers as a "reality
> check," such that I buy properly the first time.
>
>
>>>IOW, I am thinking that I need 32 258mm spokes and 32 260mm spokes. I
>>>would not wish to buy the wrong lengths, so I am imploring the experts
>>>to review my calculations before I open my wallet, or get them laced
>>>up.
>
>
> Thanks, Jim,

 

[jim beam]

Sheldon Brown wrote:
> jim beam wrote:
>
>>> one comment: "swaged" is a specific term for just one spoke
>>> manufacture process - the hammering process used by d.t. the correct
>>> generic product term is "butted" because that includes the other
>>> processes used like drawing [sapim] & grinding [wheelsmith].
>>
>>
> R.F. Jones replied:
>
>>
>> I'm not sure that drawing and butting are the same. And grinding is
>> none of the three!
>
>
> "Butting" is not a specific process. It can refer to any means of
> producing a butted (thicker on one or both ends) part.
>
> Swaging is cold working, generally done by impact. Strictly speaking,
> all spokes are swaged, 'cause that's how the heads are made.

head formation is usually called "upsetting" not swaging.

http://www.machinedesign.com/ASP/strArticleID/56082/strSite/MDSite/viewSelectedArticle.asp

>
> Drawing is stretching past the yield point, and I believe it's commonly
> done between rollers. This is how all wire products are made.
>
> Sheldon "Semantics" Brown
> Newtonville, Massachusetts
> +-----------------------------------------+
> | Man invented language to satisfy his |
> | deep need to complain. -- Lily Tomlin |
> +-----------------------------------------+
> Harris Cyclery, West Newton, Massachusetts
> Phone 617-244-9772 FAX 617-244-1041
> http://harriscyclery.com
> Hard-to-find parts shipped Worldwide
> http://captainbike.com http://sheldonbrown.com
>

 

[daveornee]

Jonesy wrote:
> Materials:
> XT M756 disk hubs, front and rear. Mavic X618 26" rims, front and rear.
> DT Competition 14/15/14 spokes/brass nipples (indeterminant length, as
> we will see.) 32-hole, 3x. The Book. Gerd Shraner's version. Sheldon's
> wheelbuild stuff, printed. Barnett's Manual.
> Two different sources put the ERD of these rims at 541mm. I get spoke
> lengths calculated thusly:
> LF, 259.9mm RF, 261.0mm LR, 261.0mm RR, 259.7mm
> I have read here and in Jobst's book (IIRC) that swaged spokes stretch
> about 0.5mm at the proper tension, and that the rim likewise
> "compresses" about the same amount. Since I have never build wheels with
> swaged spokes before, I want to make sure I order the proper length
> spokes (and nipples, if that's a concern.)
> If I use regular, DT 12mm 14ga. nipples, does that work OK with this
> rim? In addition, the spokes only come in even lengths (as far as I can
> find), so I am guessing that I need half to be 258, and the other 260,
> and that some (~1mm) of thread will be exposed on the LF and RR.
> IOW, I am thinking that I need 32 258mm spokes and 32 260mm spokes. I
> would not wish to buy the wrong lengths, so I am imploring the experts
> to review my calculations before I open my wallet, or get them laced up.
> Thank you very much (and for the opportunity to talk about technical
> issues surrounding bicycles, rather than the American political system
> and it's players.)
> --
> Robert F. Jones



I looked over your work and your numbers sound OK. Your plans for the
standard DT 12 mm nipples is OK. Check to see if your library can get
you a copy of " the Bicycle Wheel" by Jobst Brandt, 629.248 BRANDT and
read it through.



--

 

[Jonesy]

jim beam <[email protected]> wrote in message news:<%[email protected]>...
> Jonesy wrote:
> >
> > I'm not sure that drawing and butting are the same. And grinding is
> > none of the three!
>
> drawing achieves butting, as does grinding.

[snip]

Sorry about my poor attempt at humor - the comment was meant to be
tongue-in-cheek. The smiley was there for that reason. Sorni might
get the joke - he's low-brow enough. LOL.

Thanks for the process info, and also for the excelsports.com list.
It unfortunately does not include Mavic X618 rims in the listed rims.

If one were to take the spoke length info on it's face, without
reading Mr. Brandt's comments on swaged spoke elongation, then I'd be
(naively?) buying 32 260mm spokes and 32 261mm spokes. While a
millimeter here or there might not be important, one of the things I
am trying to avoid is getting them too long - I do not want the spoke
out through the bottom of the nipple.

Last time I built a wheel, I used cheap spokes and didn't care much
because I could trade them for different lengths at my LBS.
Unfortunately I am not in the same position this time, and I must
mail-order my spokes if I want anything less than a box of 100.

Although, if I read your comments correctly, I could probably get away
with using 64 260mm spokes. This seems counter-intuitive. It would
be nice to hear Mr. Brandt's opinion on this. Mr. Brown might also
wish to throw in his $0.02.

Thanks again,
--
Robert Jones

 

[Jonesy]

daveornee <[email protected]> wrote in message news:<[email protected]>...
>
> I looked over your work and your numbers sound OK. Your plans for the
> standard DT 12 mm nipples is OK. Check to see if your library can get
> you a copy of " the Bicycle Wheel" by Jobst Brandt, 629.248 BRANDT and
> read it through.

I have that book, in addition to some others. Gerd Schraner's book,
while being less than scientifically accurate, does give a nice series
of steps for lacing a 32-spoke wheel.

Unfortunately, I'm getting sort of mixed signals (well, minorly so)
about how critical the spoke length is when it comes to swaged spokes.
If I read Jim's comments correctly, then a box of 100 260mm 14/15/14
DT Competition spokes and 14 ga. 12mm nipples will be all I need to
build these wheels properly. I'd even have enough left over for a
spare wheel.

If a couple of millimeters either way isn't critical, then a box of
100 spokes would be my choice - all from the same batch, cheaper to
buy in bulk, easier to keep track of one length of spoke over - *gasp*
- two lengths, LOL. You get the picture...

Thanks for the reality check,
--
Robert Jones

 

[Jonesy]

Sheldon Brown <[email protected]> wrote in message news:<[email protected]>...
> jim beam wrote:
>
> >>one comment: "swaged" is a specific term for just one spoke manufacture
> >>process - the hammering process used by d.t. the correct generic
> >>product term is "butted" because that includes the other processes used
> >>like drawing [sapim] & grinding [wheelsmith].
> >
> R.F. Jones replied:
> >
> > I'm not sure that drawing and butting are the same. And grinding is
> > none of the three!
>
> "Butting" is not a specific process. [snip]

I was trying (poorly) to be funny. Sorry it didn't come out well.

I try and curb that impulse henceforth.

I was hoping more for a reality check on my numbers. After having
done a google groups search for commentary about swaged spokes, I
figured I'd better get some consensus of opinion before I go out and
spend money somewhere. It used to be that my LBS carried DT
Competition spokes, and I could buy however many in whatever length
suited my fancy. But that LBS is not very L anymore, due to it being
in another state and all. (Another joke, my apologies.)

So now, I actually have to think about what I'm doing and buying
before I do it.

As I mentioned in the other posts, it would really suit me fine if I
could buy a box of 260mm spokes and that would be good enough - or get
half 260 and half 261, or half 258 and half 260 - or I'm obsessing
over nothing, Jim Beam is 100% right, and I can just relax a little.

Tell me, oh Wise Pedantic One (another joke, sorry again), what would
the wise course be?

Thanks,
--
Robert F. Jones "who thinks Lily Tomlin is pretty funny - especially
her 'Laugh In' days"

 

[jim beam]

Jonesy wrote:
> jim beam <[email protected]> wrote in message news:<%[email protected]>...
>
>>Jonesy wrote:
>>
>>>I'm not sure that drawing and butting are the same. And grinding is
>>>none of the three!
>>
>>drawing achieves butting, as does grinding.
>
>
> [snip]
>
> Sorry about my poor attempt at humor - the comment was meant to be
> tongue-in-cheek. The smiley was there for that reason. Sorni might
> get the joke - he's low-brow enough. LOL.
>
> Thanks for the process info, and also for the excelsports.com list.
> It unfortunately does not include Mavic X618 rims in the listed rims.

it's practically the same as the x517, so use that figure. if you want
to recalculate yourself, mavic list the x618's e.r.d. as 539mm.

>
> If one were to take the spoke length info on it's face, without
> reading Mr. Brandt's comments on swaged spoke elongation, then I'd be
> (naively?) buying 32 260mm spokes and 32 261mm spokes. While a
> millimeter here or there might not be important, one of the things I
> am trying to avoid is getting them too long - I do not want the spoke
> out through the bottom of the nipple.

with the above figures & elongation at 100kgf, i calculated and used
258mm & 260mm for both front & rear. wheels built up fine. spokes come
up to the bottom of the drive slot in the nipple both sides.

>
> Last time I built a wheel, I used cheap spokes and didn't care much
> because I could trade them for different lengths at my LBS.
> Unfortunately I am not in the same position this time, and I must
> mail-order my spokes if I want anything less than a box of 100.
>
> Although, if I read your comments correctly, I could probably get away
> with using 64 260mm spokes. This seems counter-intuitive.

"intuition" depends on the data available. if you know from stress
analysis that the load is only supported by the first 3 threads [unless
you go to pipe threading or something non-parallel like that] then does
that change your intuition? as long as the spokes are not too long for
the threads to bind, and are not too short for the threads to show
[/and/ still long enough to allow the wheel to be built and tensoned!]
it doesn't matter. people fret about having spokes all the way through
to the top of the nipple needlessly imo.

> It would
> be nice to hear Mr. Brandt's opinion on this. Mr. Brown might also
> wish to throw in his $0.02.
>
> Thanks again,

 

[[email protected]]

Jonesy ? writes:

> I was hoping more for a reality check on my numbers. After having
> done a Google groups search for commentary about swaged spokes, I
> figured I'd better get some consensus of opinion before I go out and
> spend money somewhere. It used to be that my LBS carried DT
> Competition spokes, and I could buy however many in whatever length
> suited my fancy. But that LBS is not very L anymore, due to it
> being in another state and all.

Don't worry about spoke elongation under tension, it is smaller than
any useful choice of spoke length. In fact regardless of spoke cross
section, you can use the same length calculation to select spokes.
That is, you treat them as being inelastic. I prefer spokes to reach
the head of the spoke nipple plus minus 1mm. With hollow section
rims, the ones we usually use, a mm of overstand presents no problem.

The only problem is that some spokes are listed as longer or shorter
than they truly are. Spoke length is measured from the inside of the
elbow to the top of the threaded end. That is the way spoke rulers
are made. They have a teardrop shaped hole, the small end of which is
the zero datum with mm and inch ruling to assess spoke length.

Sampling spokes from various manufacturers, some do not measure the
same as the markings on the package. Contributors to wreck.bike have
made measurements and reported about that here. I don't have such a
sample and have used only DT and a DT Spoke ruler for many years.

Jobst Brandt
[email protected]

 

[Gary Young]

jim beam wrote:
>
> spoke length is not ultra-critical. nearest mm is more than good
> enough. the fact that manufacturers supply spokes in only 2mm
> increments ought to give you some comfort in this regard.
>
DT spokes are supplied in 1mm increments. Not that that makes spoke
length ultra-critical, but I wonder why you feel the need to sow
misinformation.


> one comment: "swaged" is a specific term for just one spoke manufacture
> process - the hammering process used by d.t. the correct generic
> product term is "butted" because that includes the other processes used
> like drawing [sapim] & grinding [wheelsmith].
>
Where do you get the idea that Wheelsmith spokes are ground? The
Wheelsmith website says they're cold worked.

 

[jim beam]

Gary Young wrote:
> jim beam wrote:
>
>>spoke length is not ultra-critical. nearest mm is more than good
>>enough. the fact that manufacturers supply spokes in only 2mm
>>increments ought to give you some comfort in this regard.
>>
>
> DT spokes are supplied in 1mm increments. Not that that makes spoke
> length ultra-critical, but I wonder why you feel the need to sow
> misinformation.

sapim are typically available in 2mm increments - please note that i
didn't state /all/ manufacturers.

>
>
>
>>one comment: "swaged" is a specific term for just one spoke manufacture
>>process - the hammering process used by d.t. the correct generic
>>product term is "butted" because that includes the other processes used
>>like drawing [sapim] & grinding [wheelsmith].
>>
>
> Where do you get the idea that Wheelsmith spokes are ground? The
> Wheelsmith website says they're cold worked.

from the wheelsmith site:
"All Wheelsmith Spokes are produced from specially drawn 304 stainless
steel using a variety of cold forging techniques, some proprietary."

yes, the main wire is cold drawn, as is all wire, but the butted section
appears to have been ground & then polished. why they feel this should
be "proprietary" is rather confusing - anyone with the tools can see how
this stuff is made. their competiton are certainly not going to be fooled.

 

[Jonesy]

[email protected] (Gary Young) wrote in message news:<[email protected]>...
> jim beam wrote:
> >
> > spoke length is not ultra-critical. nearest mm is more than good
> > enough. the fact that manufacturers supply spokes in only 2mm
> > increments ought to give you some comfort in this regard.
> >
> DT spokes are supplied in 1mm increments. Not that that makes spoke
> length ultra-critical, but I wonder why you feel the need to sow
> misinformation.

It is quite hard to find DT Competition spokes in 259mm, and I have
seen several places list that they size these in "even lengths up to
260, and millimeter sizes past that" or some such.

I imagine that 259mm spokes might only come in boxes of 100, if one
wanted to mail-order them.

I am getting the idea that spoke length is not ultra-critical.

[vbg]
--
Jonesy

 

[Benjamin Lewis]

jim beam wrote:

> from the wheelsmith site:
> "All Wheelsmith Spokes are produced from specially drawn 304 stainless
> steel using a variety of cold forging techniques, some proprietary."
>
> yes, the main wire is cold drawn, as is all wire, but the butted section
> appears to have been ground & then polished. why they feel this should
> be "proprietary" is rather confusing - anyone with the tools can see how
> this stuff is made. their competiton are certainly not going to be
> fooled.

They probably don't care. They can still make vague insinuations that
their products are superior to others due to some amazing "proprietary"
technology, and they can just say "sorry, proprietary!" if anyone calls
them on it. Very convenient, really.

--
Benjamin Lewis

TO ARMS! TO ARMS! Hooray! That's great
Two legs ain't bad unless there's a crate
They ship the parts to mama in. -- FZ

 

[Jonesy]

[email protected] wrote in message news:<[email protected]>...
> Jonesy ? writes:
>
> > I was hoping more for a reality check on my numbers. After having
> > done a Google groups search for commentary about swaged spokes, I
> > figured I'd better get some consensus of opinion before I go out and
> > spend money somewhere. It used to be that my LBS carried DT
> > Competition spokes, and I could buy however many in whatever length
> > suited my fancy. But that LBS is not very L anymore, due to it
> > being in another state and all.
>
> Don't worry about spoke elongation under tension, it is smaller than
> any useful choice of spoke length. In fact regardless of spoke cross
> section, you can use the same length calculation to select spokes.
> That is, you treat them as being inelastic. I prefer spokes to reach
> the head of the spoke nipple plus minus 1mm. With hollow section
> rims, the ones we usually use, a mm of overstand presents no problem.

Ahh, OK. Thank you.

From my calculations, it seems as though I actually can use a single
length of spoke all around (!!!) Since all the calculated lengths are
within 1.3mm of one another (259.7mm - 261.0mm), it seems that I can
get away with a box of 260mm spokes.

> The only problem is that some spokes are listed as longer or shorter
> than they truly are. Spoke length is measured from the inside of the
> elbow to the top of the threaded end. That is the way spoke rulers
> are made. They have a teardrop shaped hole, the small end of which is
> the zero datum with mm and inch ruling to assess spoke length.
>
> Sampling spokes from various manufacturers, some do not measure the
> same as the markings on the package. Contributors to wreck.bike have
> made measurements and reported about that here. I don't have such a
> sample and have used only DT and a DT Spoke ruler for many years.

Since I am planning on using DT spokes, does this mean that the
measurements provided from DT are accurate (according to your sample)?

Thanks (and for The Book as well),
--
Robert Jones

 

[Jonesy]

jim beam <[email protected]> wrote in message news:<[email protected]>...
> Jonesy wrote:
> > jim beam <[email protected]> wrote in message news:<%[email protected]>...
> >
> it's practically the same as the x517, so use that figure. if you want
> to recalculate yourself, mavic list the x618's e.r.d. as 539mm.

Really? Where? I got 541 as the ERD. A couple of mm wrong - me
buying too long, and having an ERD that's actually smaller than what I
used to do my calculations might screw my stuff up!

> > If one were to take the spoke length info on it's face, without
> > reading Mr. Brandt's comments on swaged spoke elongation, then I'd be
> > (naively?) buying 32 260mm spokes and 32 261mm spokes. While a
> > millimeter here or there might not be important, one of the things I
> > am trying to avoid is getting them too long - I do not want the spoke
> > out through the bottom of the nipple.
>
> with the above figures & elongation at 100kgf, i calculated and used
> 258mm & 260mm for both front & rear. wheels built up fine. spokes come
> up to the bottom of the drive slot in the nipple both sides.

That leaves 2mm to spare, which is plenty good.

> > Last time I built a wheel, I used cheap spokes and didn't care much
> > because I could trade them for different lengths at my LBS.
> > Unfortunately I am not in the same position this time, and I must
> > mail-order my spokes if I want anything less than a box of 100.
> >
> > Although, if I read your comments correctly, I could probably get away
> > with using 64 260mm spokes. This seems counter-intuitive.
>
> "intuition" depends on the data available. if you know from stress
> analysis that the load is only supported by the first 3 threads [unless
> you go to pipe threading or something non-parallel like that] then does
> that change your intuition?

I am going by my previous builds, and by what I have read. Your info
doesn't change anything, because I do not know how it applies.

> as long as the spokes are not too long for
> the threads to bind, and are not too short for the threads to show
> [/and/ still long enough to allow the wheel to be built and tensoned!]
> it doesn't matter. people fret about having spokes all the way through
> to the top of the nipple needlessly imo.

My major concern is them sticking out the bottom past the nipple such
that they might be a hassle for keeping tubes inflated. Stan's
NoTubes would be a way around that, but I would just prefer getting
the correct-length spokes to begin with, LOL.

One mm too short would probably not hurt anything. Two mm too long
might be cause for concern on the tube-puncturing front.
--
Jonesy

 

[jim beam]

Jonesy wrote:
> jim beam <[email protected]> wrote in message news:<[email protected]>...
>
>>Jonesy wrote:
>>
>>>jim beam <[email protected]> wrote in message news:<%[email protected]>...
>>>
>>
>>it's practically the same as the x517, so use that figure. if you want
>>to recalculate yourself, mavic list the x618's e.r.d. as 539mm.
>
>
> Really? Where? I got 541 as the ERD. A couple of mm wrong - me
> buying too long, and having an ERD that's actually smaller than what I
> used to do my calculations might screw my stuff up!

got it from a pdf on the mavictech web site a while back - it's now
password protected or i'd give you the url. i've not had a problem with
the results that figure gives. the spokes come dead level with the
bottom of the slot in the nipple head.

>
>
>>>If one were to take the spoke length info on it's face, without
>>>reading Mr. Brandt's comments on swaged spoke elongation, then I'd be
>>>(naively?) buying 32 260mm spokes and 32 261mm spokes. While a
>>>millimeter here or there might not be important, one of the things I
>>>am trying to avoid is getting them too long - I do not want the spoke
>>>out through the bottom of the nipple.
>>
>>with the above figures & elongation at 100kgf, i calculated and used
>>258mm & 260mm for both front & rear. wheels built up fine. spokes come
>>up to the bottom of the drive slot in the nipple both sides.
>
>
> That leaves 2mm to spare, which is plenty good.
>
>
>>>Last time I built a wheel, I used cheap spokes and didn't care much
>>>because I could trade them for different lengths at my LBS.
>>>Unfortunately I am not in the same position this time, and I must
>>>mail-order my spokes if I want anything less than a box of 100.
>>>
>>>Although, if I read your comments correctly, I could probably get away
>>>with using 64 260mm spokes. This seems counter-intuitive.
>>
>>"intuition" depends on the data available. if you know from stress
>>analysis that the load is only supported by the first 3 threads [unless
>>you go to pipe threading or something non-parallel like that] then does
>>that change your intuition?
>
>
> I am going by my previous builds, and by what I have read. Your info
> doesn't change anything, because I do not know how it applies.

not trying to be rude - /my/ intuition depends on the data available
[and whether it's accurate].

>
>
>> as long as the spokes are not too long for
>>the threads to bind, and are not too short for the threads to show
>>[/and/ still long enough to allow the wheel to be built and tensoned!]
>>it doesn't matter. people fret about having spokes all the way through
>>to the top of the nipple needlessly imo.
>
>
> My major concern is them sticking out the bottom past the nipple such
> that they might be a hassle for keeping tubes inflated. Stan's
> NoTubes would be a way around that, but I would just prefer getting
> the correct-length spokes to begin with, LOL.

ymmv, but my 258/260 spokes in combination with that model hub & x618's
worked just dandy.

>
> One mm too short would probably not hurt anything. Two mm too long
> might be cause for concern on the tube-puncturing front.

 

[[email protected]]

Robert Jones writes:

> From my calculations, it seems as though I actually can use a single
> length of spoke all around (!!!) Since all the calculated lengths
> are within 1.3mm of one another (259.7mm - 261.0mm), it seems that I
> can get away with a box of 260mm spokes.

You are fortunate. I guess you have little dish in the rear wheel and
about the same flange spacing. That was a feature I liked about
building track wheels for my friends.

>> The only problem is that some spokes are listed as longer or
>> shorter than they truly are. Spoke length is measured from the
>> inside of the elbow to the top of the threaded end. That is the
>> way spoke rulers are made. They have a teardrop shaped hole, the
>> small end of which is the zero datum with mm and inch ruling to
>> assess spoke length.

>> Sampling spokes from various manufacturers, some do not measure the
>> same as the markings on the package. Contributors to wreck.bike
>> have made measurements and reported about that here. I don't have
>> such a sample and have used only DT and a DT Spoke ruler for many
>> years.

> Since I am planning on using DT spokes, does this mean that the
> measurements provided from DT are accurate (according to your
> sample)?

Yes, from my experience that works.

> Thanks (and for The Book as well),

And thanks for using it.

Jobst Brandt
[email protected]