Spoke hole size in hubs

[[email protected]]

Hi all
I building a wheel w/ Sapim 2.0 /1.8 spokes & an XT M752 rear hub.
Shimano lists the size of the spoke holes is 2.6mm, which I have
confirmed w/ a digital caliber. When I insert a spoke, it rattles
around quite a bit. I have been unable to find this problem addressed
in "The Book".
Two questions:
1. Am I just missing this subject in "The Book"? If so, what
page(s)?
2. What do rbt wheel builders do about this situation. Do you use DT
Spoke washers? However due to the fact that Sapim does not make the "J"
end of their spokes as long as DT does, won't the spokes leaving the
holes be forced into too oblique of an angle, making it difficult, if
not impossible to flatten them against the hub?
Best Wishes, for the Holidays, John

 

[daveornee]

Hi all
I building a wheel w/ Sapim 2.0 /1.8 spokes & an XT M752 rear hub.
Shimano lists the size of the spoke holes is 2.6mm, which I have
confirmed w/ a digital caliber. When I insert a spoke, it rattles
around quite a bit. I have been unable to find this problem addressed
in "The Book".
Two questions:
1. Am I just missing this subject in "The Book"? If so, what
page(s)?
2. What do rbt wheel builders do about this situation. Do you use DT
Spoke washers? However due to the fact that Sapim does not make the "J"
end of their spokes as long as DT does, won't the spokes leaving the
holes be forced into too oblique of an angle, making it difficult, if
not impossible to flatten them against the hub?
Best Wishes, for the Holidays, John

1. I didn't see any mention in the edition I have. This is situation normal as hubs are often designed for ease of machine building. There is no advantage in having the holes that large.

2. If you follow the information on "Improving the spoke line at the hub" you will find it works well when the final tension is reached. Spoke washers are not needed.

 

[jim beam]

daveornee wrote:
> [email protected] Wrote:
>
>>Hi all
>>I building a wheel w/ Sapim 2.0 /1.8 spokes & an XT M752 rear hub.
>>Shimano lists the size of the spoke holes is 2.6mm, which I have
>>confirmed w/ a digital caliber. When I insert a spoke, it rattles
>>around quite a bit. I have been unable to find this problem addressed
>>in "The Book".
>>Two questions:
>>1. Am I just missing this subject in "The Book"? If so, what
>>page(s)?
>>2. What do rbt wheel builders do about this situation. Do you use DT
>>Spoke washers? However due to the fact that Sapim does not make the
>>"J"
>>end of their spokes as long as DT does, won't the spokes leaving the
>>holes be forced into too oblique of an angle, making it difficult, if
>>not impossible to flatten them against the hub?
>>Best Wishes, for the Holidays, John
>
>
> 1. I didn't see any mention in the edition I have. This is situation
> normal as hubs are often designed for ease of machine building. There
> is no advantage in having the holes that large.
>
> 2. If you follow the information on "Improving the spoke line at the
> hub" you will find it works well when the final tension is reached.
> Spoke washers are not needed.

"improving the spoke line" is bad advice.

1. it's more likely to create a residual stress problem than leaving alone.

2. the settled angle of a spoke elbow in a properly bedded in hub is
about 95 degrees. making that angle more acute by "improving the line"
before the spokes are all tensioned is working against final alignment,
not with it.

3. check sapim's web site - they specifically recommend against this
practice.

 

[daveornee]

daveornee wrote:
> [email protected] Wrote:
>
>>Hi all
>>I building a wheel w/ Sapim 2.0 /1.8 spokes & an XT M752 rear hub.
>>Shimano lists the size of the spoke holes is 2.6mm, which I have
>>confirmed w/ a digital caliber. When I insert a spoke, it rattles
>>around quite a bit. I have been unable to find this problem addressed
>>in "The Book".
>>Two questions:
>>1. Am I just missing this subject in "The Book"? If so, what
>>page(s)?
>>2. What do rbt wheel builders do about this situation. Do you use DT
>>Spoke washers? However due to the fact that Sapim does not make the
>>"J"
>>end of their spokes as long as DT does, won't the spokes leaving the
>>holes be forced into too oblique of an angle, making it difficult, if
>>not impossible to flatten them against the hub?
>>Best Wishes, for the Holidays, John
>
>
> 1. I didn't see any mention in the edition I have. This is situation
> normal as hubs are often designed for ease of machine building. There
> is no advantage in having the holes that large.
>
> 2. If you follow the information on "Improving the spoke line at the
> hub" you will find it works well when the final tension is reached.
> Spoke washers are not needed.

"improving the spoke line" is bad advice.

1. it's more likely to create a residual stress problem than leaving alone.

2. the settled angle of a spoke elbow in a properly bedded in hub is
about 95 degrees. making that angle more acute by "improving the line"
before the spokes are all tensioned is working against final alignment,
not with it.

3. check sapim's web site - they specifically recommend against this
practice.

I made no suggestion of changing the angle.
What do you mean by "properly bedded hub"?
I remove residual stress by stress relieving.

 

[B Paton]

<[email protected]> wrote in message
news:[email protected]...
> Hi all
> I building a wheel w/ Sapim 2.0 /1.8 spokes & an XT M752 rear hub.
> Shimano lists the size of the spoke holes is 2.6mm, which I have
> confirmed w/ a digital caliber. When I insert a spoke, it rattles
> around quite a bit. I have been unable to find this problem addressed
> in "The Book".

Gerd Shraner's book ( The Art of Wheelbuilding) deals with this topic
extensively. He would probably recommend washers and punching the spoke
heads to set them.

He points out that most spoke failures occur at the hub flange (not really
news to any of us). He claims this has 2 causes:
1) Improper spoke tension leading to shearing (too high) or spontaneous
loosening (too low) and imbalance in the wheel.

2) A hole at the flange that is too large, which causes wear at the elbow
due to stressing and unstressing as the wheel rotates.

He is very clear about the need to do so when dealing with a large hub
flange hole.

Cheers,
Blake

 

[[email protected]]

Hi Blake and thanks for the other replies.
Punching the spoke heads scares the hell out of me. I've tired it &
blows that seem light enough to not damage the flg. don't cause any
change. The price for finding out how much force it takes to seat the
spoke head may be a broken flg. Do you have any suggestions for
exploring this limit w/o exceeding it?
John

 

[B Paton]

<[email protected]> wrote in message
news:[email protected]...
>The price for finding out how much force it takes to seat the
> spoke head may be a broken flg. Do you have any suggestions for
> exploring this limit w/o exceeding it?
> John
>

A good, stiff rap, is what works for me. I have not used the technique with
washers, though. I believe that the suggestion is that you set them after
initial tensioning and before final trueing and stress-relieving. The change
is not much visible to the naked eye, but Shraner swears by the method, and
he is a widely acknowledged master of the art. A dremel tool on a standard
punch can easily replace the DT purpose-built punch.
Blake

 

[jim beam]

[email protected] wrote:
> Hi Blake and thanks for the other replies.
> Punching the spoke heads scares the hell out of me. I've tired it &
> blows that seem light enough to not damage the flg. don't cause any
> change. The price for finding out how much force it takes to seat the
> spoke head may be a broken flg. Do you have any suggestions for
> exploring this limit w/o exceeding it?
> John
>

your original question was whether to worry about a 2.6mm hole for a
2.0mm spoke. basically, no - it's the same diameter difference as a
2.4mm hole & a 1.8mm spoke, a very common combination.

as for washers & head punching, i'd not bother unless there were issues
with the length of the spoke elbow. d.t. can be longer than sapim, so
if this worries you, and you want the shorter elbow, go sapim. you can
also get d.t. "strong" which have a 2.3mm diameter at the elbow, but
they are even longer for the thick flanges on tandem hubs, so what you
gain on one hand, you lose on another. bottom line, although
manufacturers make mistakes from time to time, i doubt you'll ever
encounter a problem conclusively attributable to shimano's choice in
spoke hole diameter.

 

[jim beam]

daveornee wrote:
> jim beam Wrote:
>
>>daveornee wrote:
>>
>>>[email protected] Wrote:
>>>
>>>
>>>>Hi all
>>>>I building a wheel w/ Sapim 2.0 /1.8 spokes & an XT M752 rear hub.
>>>>Shimano lists the size of the spoke holes is 2.6mm, which I have
>>>>confirmed w/ a digital caliber. When I insert a spoke, it rattles
>>>>around quite a bit. I have been unable to find this problem
>>
>>addressed
>>
>>>>in "The Book".
>>>>Two questions:
>>>>1. Am I just missing this subject in "The Book"? If so, what
>>>>page(s)?
>>>>2. What do rbt wheel builders do about this situation. Do you use DT
>>>>Spoke washers? However due to the fact that Sapim does not make the
>>>>"J"
>>>>end of their spokes as long as DT does, won't the spokes leaving the
>>>>holes be forced into too oblique of an angle, making it difficult,
>>
>>if
>>
>>>>not impossible to flatten them against the hub?
>>>>Best Wishes, for the Holidays, John
>>>
>>>
>>>1. I didn't see any mention in the edition I have. This is
>>
>>situation
>>
>>>normal as hubs are often designed for ease of machine building.
>>
>>There
>>
>>>is no advantage in having the holes that large.
>>>
>>>2. If you follow the information on "Improving the spoke line at
>>
>>the
>>
>>>hub" you will find it works well when the final tension is reached.
>>>Spoke washers are not needed.
>>
>>"improving the spoke line" is bad advice.
>>
>>1. it's more likely to create a residual stress problem than leaving
>>alone.
>>
>>2. the settled angle of a spoke elbow in a properly bedded in hub is
>>about 95 degrees. making that angle more acute by "improving the
>>line"
>>before the spokes are all tensioned is working against final
>>alignment,
>>not with it.
>>
>>3. check sapim's web site - they specifically recommend against this
>>practice.
>
>
> I made no suggestion of changing the angle.

no personal criticism intended dave - it's just that the quote
"Improving the spoke line at the hub" means bending the spoke and
therefore changing its elbow angle.

> What do you mean by "properly bedded hub"?

"bedding in" is just over-stressing the spoke. this results in local
yielding at the hub hole, as evident in any hub from a disassembled
wheel. while this process is commonly referred to "stress relief", i've
yet to see any evidence that it offers stress relief in the
metallurgical sense. "stress relief", "setting", "bedding in", whatever
you want to call it, is however an essential part of wheelbuilding so
regardless of name, the practice is a good one.

> I remove residual stress by stress relieving.

that there is residual stress in a highly cold worked wire that can be
relieved by a a sub-yield load is a theory that is at best a wild stab
in the dark. especially when that theory is based on a fundamental
misconception about a strain aging deformation mode of a material that
does not exhibit those properties.

 

[daveornee]

daveornee wrote:
> jim beam Wrote:
>
>>daveornee wrote:
>>
>>>[email protected] Wrote:
>>>
>>>
>>>>Hi all
>>>>I building a wheel w/ Sapim 2.0 /1.8 spokes & an XT M752 rear hub.
>>>>Shimano lists the size of the spoke holes is 2.6mm, which I have
>>>>confirmed w/ a digital caliber. When I insert a spoke, it rattles
>>>>around quite a bit. I have been unable to find this problem
>>
>>addressed
>>
>>>>in "The Book".
>>>>Two questions:
>>>>1. Am I just missing this subject in "The Book"? If so, what
>>>>page(s)?
>>>>2. What do rbt wheel builders do about this situation. Do you use DT
>>>>Spoke washers? However due to the fact that Sapim does not make the
>>>>"J"
>>>>end of their spokes as long as DT does, won't the spokes leaving the
>>>>holes be forced into too oblique of an angle, making it difficult,
>>
>>if
>>
>>>>not impossible to flatten them against the hub?
>>>>Best Wishes, for the Holidays, John
>>>
>>>
>>>1. I didn't see any mention in the edition I have. This is
>>
>>situation
>>
>>>normal as hubs are often designed for ease of machine building.
>>
>>There
>>
>>>is no advantage in having the holes that large.
>>>
>>>2. If you follow the information on "Improving the spoke line at
>>
>>the
>>
>>>hub" you will find it works well when the final tension is reached.
>>>Spoke washers are not needed.
>>
>>"improving the spoke line" is bad advice.
>>
>>1. it's more likely to create a residual stress problem than leaving
>>alone.
>>
>>2. the settled angle of a spoke elbow in a properly bedded in hub is
>>about 95 degrees. making that angle more acute by "improving the
>>line"
>>before the spokes are all tensioned is working against final
>>alignment,
>>not with it.
>>
>>3. check sapim's web site - they specifically recommend against this
>>practice.
>
>
> I made no suggestion of changing the angle.

no personal criticism intended dave - it's just that the quote
"Improving the spoke line at the hub" means bending the spoke and
therefore changing its elbow angle.

> What do you mean by "properly bedded hub"?

"bedding in" is just over-stressing the spoke. this results in local
yielding at the hub hole, as evident in any hub from a disassembled
wheel. while this process is commonly referred to "stress relief", i've
yet to see any evidence that it offers stress relief in the
metallurgical sense. "stress relief", "setting", "bedding in", whatever
you want to call it, is however an essential part of wheelbuilding so
regardless of name, the practice is a good one.

> I remove residual stress by stress relieving.

that there is residual stress in a highly cold worked wire that can be
relieved by a a sub-yield load is a theory that is at best a wild stab
in the dark. especially when that theory is based on a fundamental
misconception about a strain aging deformation mode of a material that
does not exhibit those properties.

When I stress relieve I apply sufficient force to make the spokes yield. Spoke alignment is either enhanced or at least not "pulled" in the wrong direction when I stress relieve. I check the spoke tension and alignment before and after stress relieving. I don't use the procedure shown in "the Bicycle Wheel" as it doesn't seem to work for me, and it may cause the spoke alignment to be lost.
I can't prove that stress relief works at the molecular level, because I don't know what the internals of the spoke look like before and after the procedure.

 

[jim beam]

daveornee wrote:
> jim beam Wrote:
>
>>daveornee wrote:
>>
>>>jim beam Wrote:
>>>
>>>
>>>>daveornee wrote:
>>>>
>>>>
>>>>>[email protected] Wrote:
>>>>>
>>>>>
>>>>>
>>>>>>Hi all
>>>>>>I building a wheel w/ Sapim 2.0 /1.8 spokes & an XT M752 rear hub.
>>>>>>Shimano lists the size of the spoke holes is 2.6mm, which I have
>>>>>>confirmed w/ a digital caliber. When I insert a spoke, it rattles
>>>>>>around quite a bit. I have been unable to find this problem
>>>>
>>>>addressed
>>>>
>>>>
>>>>>>in "The Book".
>>>>>>Two questions:
>>>>>>1. Am I just missing this subject in "The Book"? If so, what
>>>>>>page(s)?
>>>>>>2. What do rbt wheel builders do about this situation. Do you use
>>
>>DT
>>
>>>>>>Spoke washers? However due to the fact that Sapim does not make
>>
>>the
>>
>>>>>>"J"
>>>>>>end of their spokes as long as DT does, won't the spokes leaving
>>
>>the
>>
>>>>>>holes be forced into too oblique of an angle, making it difficult,
>>>>
>>>>if
>>>>
>>>>
>>>>>>not impossible to flatten them against the hub?
>>>>>>Best Wishes, for the Holidays, John
>>>>>
>>>>>
>>>>>1. I didn't see any mention in the edition I have. This is
>>>>
>>>>situation
>>>>
>>>>
>>>>>normal as hubs are often designed for ease of machine building.
>>>>
>>>>There
>>>>
>>>>
>>>>>is no advantage in having the holes that large.
>>>>>
>>>>>2. If you follow the information on "Improving the spoke line at
>>>>
>>>>the
>>>>
>>>>
>>>>>hub" you will find it works well when the final tension is reached.
>>>>>Spoke washers are not needed.
>>>>
>>>>"improving the spoke line" is bad advice.
>>>>
>>>>1. it's more likely to create a residual stress problem than leaving
>>>>alone.
>>>>
>>>>2. the settled angle of a spoke elbow in a properly bedded in hub is
>>>>about 95 degrees. making that angle more acute by "improving the
>>>>line"
>>>>before the spokes are all tensioned is working against final
>>>>alignment,
>>>>not with it.
>>>>
>>>>3. check sapim's web site - they specifically recommend against this
>>>>practice.
>>>
>>>
>>>I made no suggestion of changing the angle.
>>
>>no personal criticism intended dave - it's just that the quote
>>"Improving the spoke line at the hub" means bending the spoke and
>>therefore changing its elbow angle.
>>
>>
>>>What do you mean by "properly bedded hub"?
>>
>>"bedding in" is just over-stressing the spoke. this results in local
>>yielding at the hub hole, as evident in any hub from a disassembled
>>wheel. while this process is commonly referred to "stress relief",
>>i've
>>yet to see any evidence that it offers stress relief in the
>>metallurgical sense. "stress relief", "setting", "bedding in",
>>whatever
>>you want to call it, is however an essential part of wheelbuilding so
>>regardless of name, the practice is a good one.
>>
>>
>>>I remove residual stress by stress relieving.
>>
>>that there is residual stress in a highly cold worked wire that can be
>>relieved by a a sub-yield load is a theory that is at best a wild stab
>>in the dark. especially when that theory is based on a fundamental
>>misconception about a strain aging deformation mode of a material that
>>does not exhibit those properties.
>
>
> When I stress relieve I apply sufficient force to make the spokes
> yield.

you apply about 300Kgf? - over 600Lbs? that's pretty unlikely - hub
holes & rims yield way before then.

> Spoke alignment is either enhanced or at least not "pulled" in
> the wrong direction when I stress relieve. I check the spoke tension
> and alignment before and after stress relieving. I don't use the
> procedure shown in "the Bicycle Wheel" as it doesn't seem to work for
> me, and it may cause the spoke alignment to be lost.

i like the procedure suggested by mavic. no spoke alignment issues
whatsoever.

> I can't prove that stress relief works at the molecular level,

from what i can see, nor can anyone else for this kind of application.

> because
> I don't know what the internals of the spoke look like before and after
> the procedure.

trust a good quality spoke manufacturer to know what they're doing.

at the end of the day dave, just keep doing what you're doing - it's the
right thing - just don't make any baseless claims about being able to
eliminate metal fatigue!

 

[[email protected]]

I was going to do the Dremel tool thing to a punch, but I saw a
perfectly dimpled punch in a H'ware store & bought it.
Thanks John

 

[daveornee]

<SNIP>

at the end of the day dave, just keep doing what you're doing - it's the right thing - just don't make any baseless claims about being able to eliminate metal fatigue![/QUOTE]


Jim Beam,

Where did I make the claim that I am eliminating metal fatigue?

Yes, I apply over 300 kgf on the spokes. The hubs hold up as do most rim holes/eyelets. Only 4 each FIR rims so far were the only ones where the eyelets pulled out. If the rims, spokes, hubs, or nipples fail while I am stressing the spokes I replace them before the wheel goes out the door.

Hitting a spoke head with a steel punch *can* cause a problem. If the punch hits the aluminum hub flange with a striking force it can start a crack in the flange. You need to be very careful with a steel punch.