DISTANCE FROM ERD TO FINAL SPOKE TORQUE?

datakoll said:

How many nipple turns are there between ERD and final spoke torque for
the road ready 36 spoke 4 cross, 36 3 cross, or 32 spoke wheels?

zero. the spoke position you see in the muzi pic is for the wheel fully
tensioned - and that is erd. below that tension, the spokes will be
further down the spoke nipple thread. crossing makes no easily
observable difference.

Jim,

"Effective Rim Diameter. This is the rim diameter measured at the
nipple seats in the spoke holes, plus the thickness of the two nipple
heads. The E.R.D. is needed for calculating the correct spoke
length." - Sheldon Brown's Glossary - I assume Sheldon read thru his
calc software.

Not where Andrew Muzi leaves his spoke ends.

Notice is this definition Sheldon, rarely incorrect, writes "is NEEDED
for calculating THE CORRECT SPOKE LENGTH" not is the correct spoke
length. Knee dead. NE sense of humor. Gotta measure the knee dead
here or ura over the 1.5mm murphy error spectrum.

You are fired dude! try the plumbing MO.

we'll throw a rope down tomorrow morning.

datakoll said:

Jim,

"Effective Rim Diameter. This is the rim diameter measured at the
nipple seats in the spoke holes, plus the thickness of the two nipple
heads. The E.R.D. is needed for calculating the correct spoke
length." - Sheldon Brown's Glossary - I assume Sheldon read thru his
calc software.

Not where Andrew Muzi leaves his spoke ends.

Notice is this definition Sheldon, rarely incorrect, writes "is NEEDED
for calculating THE CORRECT SPOKE LENGTH" not is the correct spoke
length. Knee dead. NE sense of humor. Gotta measure the knee dead
here or ura over the 1.5mm murphy error spectrum.

Of course ERD is not spoke length, unless you lace your wheels
diametrically with straight spokes and don't use a hub.

People, but not everyone, do really use nipple seat diameter *plus
thickness of two nipple heads* in the calculators, with the intention of
leaving the spoke ends about 1.5mm higher than those in Andrew Muzi's
picture.

Like you I am a bit mystified about the purpose of the extra few
millimetres. Jim did give an answer which was that with the spokes a bit
longer lacing may be easier.

If the nipples are short, lacing could be tricky if spokes are on the
short side.

datakoll said:

Jim,
"Effective Rim Diameter. This is the rim diameter measured at the
nipple seats in the spoke holes, plus the thickness of the two nipple
heads. The E.R.D. is needed for calculating the correct spoke
length." - Sheldon Brown's Glossary - I assume Sheldon read thru his
calc software.
Not where Andrew Muzi leaves his spoke ends.
Notice is this definition Sheldon, rarely incorrect, writes "is NEEDED
for calculating THE CORRECT SPOKE LENGTH" not is the correct spoke
length. Knee dead. NE sense of humor. Gotta measure the knee dead
here or ura over the 1.5mm murphy error spectrum.
You are fired dude! try the plumbing MO.
we'll throw a rope down tomorrow morning.

I wasn't suggesting _everyone_ calc spokes as we do, only explaining why
we choose this format for wheelbuilding here.

Moreover, any length between seat of nipple (photo) and top of nipple
(Jobst's suggestion) is perfectly functional. There's no good reason to
anguish over a 2~3mm variance in spoke length within that range.

Others have exhaustively explained various rim ERD measurement methods.

In short, since you've built it and found your spokes 6mm* long, choose
a length 6mm* shorter than that and build it!

In the days before painlessly accessible computer spoke calc programs,
we used a wall chart**. That's an excellent method. Once having built a
wheel, one records the hub, rim, drill, F/R, cross and length. Even if
the length is not ideal (2mm long for example) one may can record the
ideal length for next time.

* or whatever it was
** We still have and use them. A chart is quicker than any program.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

Ben C said:

datakoll said:

Jim,

Quoted message said:

"Effective Rim Diameter. This is the rim diameter measured at the
nipple seats in the spoke holes, plus the thickness of the two nipple
heads. The E.R.D. is needed for calculating the correct spoke
length."  - Sheldon Brown's Glossary - I assume Sheldon read thru his
calc software.

Quoted message said:

Not where Andrew Muzi leaves his spoke ends.

Quoted message said:

Notice is this definition Sheldon, rarely incorrect, writes "is NEEDED
for calculating THE CORRECT SPOKE LENGTH"  not is the correct spoke
length.  Knee dead. NE sense of humor. Gotta measure the knee dead
here or ura over the 1.5mm murphy error spectrum.

Of course ERD is not spoke length, unless you lace your wheels
diametrically with straight spokes and don't use a hub.

People, but not everyone, do really use nipple seat diameter *plus
thickness of two nipple heads* in the calculators, with the intention of
leaving the spoke ends about 1.5mm higher than those in Andrew Muzi's
picture.

Like you I am a bit mystified about the purpose of the extra few
millimetres. Jim did give an answer which was that with the spokes a bit
longer lacing may be easier.

If the nipples are short, lacing could be tricky if spokes are on the
short side.

right. I am missing the point. Here are 2-3 experts telling me a spoke
length approaching and exceeding a non-workable spoke length from
overrrunning available threading IS A GOOD IDEA.
I assume ERD is minus the hub. But if not then I'll am going to work
over some spoke calcs.
My opinion of the experts opinion whose opnion I respect is the ERD is
LBS oriented. An overly long spoke length up to the nipple seat/outer
eyelet/outer rim surface (longest diameters from hub) using almost all
available threading is easier to build quickly as the structure is
more self supporting and when 'excessive' wear uses up the available
threading making the wheel unuseable unless rebuilt or a spoke opos
tubes then that's to the LBS advantage. An around the block, low
mileage wheel build.
For the DIY builder, using 90%+ the available spoke threading is
nowhere.
Is there a DIY friendly spoke calc?

Quoted message said:

Quoted message said:

datakoll said:

Jim,
"Effective Rim Diameter. This is the rim diameter measured at the
nipple seats in the spoke holes, plus the thickness of the two nipple
heads. The E.R.D. is needed for calculating the correct spoke
length." - Sheldon Brown's Glossary - I assume Sheldon read thru his
calc software.
Not where Andrew Muzi leaves his spoke ends.
Notice is this definition Sheldon, rarely incorrect, writes "is NEEDED
for calculating THE CORRECT SPOKE LENGTH" not is the correct spoke
length. Knee dead. NE sense of humor. Gotta measure the knee dead
here or ura over the 1.5mm murphy error spectrum.

Quoted message said:

Ben C said:

Of course ERD is not spoke length, unless you lace your wheels
diametrically with straight spokes and don't use a hub.
People, but not everyone, do really use nipple seat diameter *plus
thickness of two nipple heads* in the calculators, with the intention of
leaving the spoke ends about 1.5mm higher than those in Andrew Muzi's
picture.
Like you I am a bit mystified about the purpose of the extra few
millimetres. Jim did give an answer which was that with the spokes a bit
longer lacing may be easier.
If the nipples are short, lacing could be tricky if spokes are on the
short side.

datakoll said:

right. I am missing the point. Here are 2-3 experts telling me a spoke
length approaching and exceeding a non-workable spoke length from
overrrunning available threading IS A GOOD IDEA.
I assume ERD is minus the hub. But if not then I'll am going to work
over some spoke calcs.
My opinion of the experts opinion whose opnion I respect is the ERD is
LBS oriented. An overly long spoke length up to the nipple seat/outer
eyelet/outer rim surface (longest diameters from hub) using almost all
available threading is easier to build quickly as the structure is
more self supporting and when 'excessive' wear uses up the available
threading making the wheel unuseable unless rebuilt or a spoke opos
tubes then that's to the LBS advantage. An around the block, low
mileage wheel build.
For the DIY builder, using 90%+ the available spoke threading is
nowhere.
Is there a DIY friendly spoke calc?

ERD is a convention. We use ERD because you need some end point for the
altitude of the various triangles for which a calc program computes the
hypotenuses. It's complex because from head to tip the spoke is the
hypotenuse of a triangle whose base is the distance from the center of
the hub laterally to the flange, also one whose base is from a 'radial'
centerline to the spoke hole, etc*.

Whether you calculate the end point as end of nipple or seat of nipple
is up to you.

I believe the only rough spot here is that some people use the top of
the nipple without explicitly saying "We're adding two nipple heights to
the rim's nipple seat". That's OK. Unless you hypercorrect and add that
depth yourself again.

*Jobst thoughtfully includes the actual equation in The Book. If you can
take square roots on paper you don't even need a computer.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

datakoll said:

Ben C said:

datakoll said:

Jim,
"Effective Rim Diameter. This is the rim diameter measured at the
nipple seats in the spoke holes, plus the thickness of the two nipple
heads. The E.R.D. is needed for calculating the correct spoke
length." �- Sheldon Brown's Glossary - I assume Sheldon read thru his
calc software.
Not where Andrew Muzi leaves his spoke ends.
Notice is this definition Sheldon, rarely incorrect, writes "is NEEDED
for calculating THE CORRECT SPOKE LENGTH" �not is the correct spoke
length. �Knee dead. NE sense of humor. Gotta measure the knee dead
here or ura over the 1.5mm murphy error spectrum.

Of course ERD is not spoke length, unless you lace your wheels
diametrically with straight spokes and don't use a hub.

People, but not everyone, do really use nipple seat diameter *plus
thickness of two nipple heads* in the calculators, with the intention of
leaving the spoke ends about 1.5mm higher than those in Andrew Muzi's
picture.

Like you I am a bit mystified about the purpose of the extra few
millimetres. Jim did give an answer which was that with the spokes a bit
longer lacing may be easier.

If the nipples are short, lacing could be tricky if spokes are on the
short side.

right. I am missing the point. Here are 2-3 experts telling me a spoke
length approaching and exceeding a non-workable spoke length from
overrrunning available threading IS A GOOD IDEA.
I assume ERD is minus the hub. But if not then I'll am going to work
over some spoke calcs.
My opinion of the experts opinion whose opnion I respect is the ERD is
LBS oriented. An overly long spoke length up to the nipple seat/outer
eyelet/outer rim surface (longest diameters from hub) using almost all
available threading is easier to build quickly as the structure is
more self supporting and when 'excessive' wear uses up the available
threading making the wheel unuseable unless rebuilt or a spoke opos
tubes then that's to the LBS advantage. An around the block, low
mileage wheel build.
For the DIY builder, using 90%+ the available spoke threading is
nowhere.
Is there a DIY friendly spoke calc?

dude, where do you get this "tolerance" idea from? especially the 10%
bit. there's not a single component on your bike that is that sloppy.
even woolmort bike shaped objects. no, bike spokes don't need to be the
same tolerance as a bearing ball, but they sure do need to be a good
deal better than 10%. less than 0.5% typically.

datakoll said:

Jim,

"Effective Rim Diameter. This is the rim diameter measured at the
nipple seats in the spoke holes, plus the thickness of the two nipple
heads. The E.R.D. is needed for calculating the correct spoke
length." - Sheldon Brown's Glossary - I assume Sheldon read thru his
calc software.

sheldon didn't write those words - they're jobst's. and he didn't write
calc s/w as far as i'm aware. but he has posted damon rinard's spoke
calculator spreadsheet.

Quoted message said:

Not where Andrew Muzi leaves his spoke ends.

Notice is this definition Sheldon, rarely incorrect, writes "is NEEDED
for calculating THE CORRECT SPOKE LENGTH" not is the correct spoke
length.

"is needed for calculating the correct spoke length" is absolutely correct.

Quoted message said:

Knee dead. NE sense of humor. Gotta measure the knee dead
here or ura over the 1.5mm murphy error spectrum.

You are fired dude! try the plumbing MO.

we'll throw a rope down tomorrow morning.

sheldon is a great and eclectic collector of useful and wonderful stuff.
however, he also has taken it upon himself to repeat a lot of jobst's
utterances on many subjects, some of which are bogus. thus the problem
of jobst's mistake becomes compounded by being "endorsed" by sheldon's
otherwise impeccable integrity.

erd should be: "the distance between two opposing rim hole seats, with
all spokes at full tension, with the appropriate spoke nipple head depth
added". absent this number being available from the rim manufacturer,
it can be measured on an un-spoked un-tensioned rim, with the
appropriate allowance for the effects of elasticity. adding a number
that would work for the bottom of the spoke nipple head slot gives
sufficient empirical leeway for elasticity.

A Muzi said:

Quoted message said:

Quoted message said:

On 2008-02-03, datakoll <[email hidden]> wrote:
> Jim,
> "Effective Rim Diameter. This is the rim diameter measured at the
> nipple seats in the spoke holes, plus the thickness of the two nipple
> heads. The E.R.D. is needed for calculating the correct spoke
> length."  - Sheldon Brown's Glossary - I assume Sheldon read thru his
> calc software.
> Not where Andrew Muzi leaves his spoke ends.
> Notice is this definition Sheldon, rarely incorrect, writes "is NEEDED
> for calculating THE CORRECT SPOKE LENGTH"  not is the correct spoke
> length.  Knee dead. NE sense of humor. Gotta measure the knee dead
> here or ura over the 1.5mm murphy error spectrum.

Ben C said:

Of course ERD is not spoke length, unless you lace your wheels
diametrically with straight spokes and don't use a hub.
People, but not everyone, do really use nipple seat diameter *plus
thickness of two nipple heads* in the calculators, with the intention of
leaving the spoke ends about 1.5mm higher than those in Andrew Muzi's
picture.
Like you I am a bit mystified about the purpose of the extra few
millimetres. Jim did give an answer which was that with the spokes a bit
longer lacing may be easier.
If the nipples are short, lacing could be tricky if spokes are on the
short side.

datakoll said:

right. I am missing the point. Here are 2-3 experts telling me a spoke
length approaching and exceeding a non-workable spoke length from
overrrunning available threading IS A GOOD IDEA.
I assume ERD is minus the hub. But if not then I'll am going to work
over some spoke calcs.
My opinion of the experts opinion whose opnion I respect is the ERD is
LBS oriented. An overly long spoke length up to the nipple seat/outer
eyelet/outer rim surface (longest diameters from hub) using almost all
available threading is easier to build quickly as the structure is
more self supporting and when 'excessive' wear uses up the available
threading making the wheel unuseable unless rebuilt or a spoke opos
tubes then that's to the LBS advantage. An around the block, low
mileage wheel build.
For the DIY builder, using 90%+ the available spoke threading is
nowhere.
Is there a DIY friendly spoke calc?

ERD is a convention. We use ERD because you need some end point for the
altitude of the various triangles for which a calc program computes the
hypotenuses. It's complex because from head to tip the spoke is the
hypotenuse of a triangle whose base is the distance from the center of
the hub laterally to the flange, also one whose base is from a 'radial'
centerline to the spoke hole, etc*.

Whether you calculate the end point as end of nipple or seat of nipple
is up to you.

I believe the only rough spot here is that some people use the top of
the nipple without explicitly saying "We're adding two nipple heights to
the rim's nipple seat". That's OK.  Unless you hypercorrect and add that
depth yourself again.

*Jobst thoughtfully includes the actual equation in The Book. If you can
take square roots on paper you don't even need a computer.
--
Andrew Muziwww.yellowjersey.org
Open every day since 1 April, 1971- Hide quoted text -

With all of Gene's agonizing, I am starting to miss the days of the
Sutherland manual that just listed the rim and the hub and gave you a
spoke length. There was no mention of ERD, and you penciled in the
odd lenths after doing trial and error. -- Jay Beattie.

the spoke calc carry a lotta weight, like Zeuss or Mephistofulleast.

the problem is functional! why are wheels set up with the ERD using
all available threading?
ERD and using all available threading are twinned here.
throwing in 'needing' and 'appropriate' isn't up to the claimed rigor.

NE is butt deep in tech cyclists for peer review and I'm sure Sheldon
ran thru various spoke calcs from curiousoity as have his friends.
What you have here is a tech element dispensing spoke calc that isn't
producing spoke calc unless yawl accept ERD as using all available
threading which is nutty, dysnfunctional. A gross parallel is
pollution is good for you because pollution stimulates profit and
profit filters down to the worker when we know pollution isn't good
for you and stimulates 3rd homes in France and Dominica.

I'm not agonzing, I'm attempting to move a large boulder. You wanna
discuss Jute's skin problem?

datakoll said:

the spoke calc carry a lotta weight, like Zeuss or Mephistofulleast.

the problem is functional! why are wheels set up with the ERD using
all available threading?

custom. convenience. practicality. and reality - too short, the wheel
is a [censored] to lace. too long, it's a [censored] to true. not all customs
are arbitrary bollocks.

Quoted message said:

ERD and using all available threading are twinned here.
throwing in 'needing' and 'appropriate' isn't up to the claimed rigor.

NE is butt deep in tech cyclists for peer review and I'm sure Sheldon
ran thru various spoke calcs from curiousoity as have his friends.
What you have here is a tech element dispensing spoke calc that isn't
producing spoke calc unless yawl accept ERD as using all available
threading which is nutty, dysnfunctional.

no, it's math. you put garbage in, you'll get garbage out. would you
specify 2x then complain that it doesn't lace to 3x?

Quoted message said:

A gross parallel is
pollution is good for you because pollution stimulates profit and
profit filters down to the worker when we know pollution isn't good
for you and stimulates 3rd homes in France and Dominica.

I'm not agonzing, I'm attempting to move a large boulder. You wanna
discuss Jute's skin problem?

no. and i don't want to discuss jute's emotional problems either. the
only large boulder for this stuff dude, is whether you can ever accept
the relevance of over a century of practical experience with this stuff
with countless millions of wheels built. successfully.