Reducing spoke wind-up with molybdenum disulfide

On 20 May 2007 11:38:24 -0700, Thomas Hood <[email hidden]>

Quoted message said:

Dear All,

I am about to build a set of wheels and it occurs to me that a
molybdenum disulfide based lube (rather than 30w engine oil) on the
threads might reduce the problem of spoke wind-up greatly.

Is it fair to extrapolate from here:
http://www.arp-bolts.com/Catalog/Catalog.PDF/ARPCatalog_0024.pdf

Thread size, Torque w/ 30W motor oil, with moly, (my calculated % less
torque for moly)
5/16? stud 25 20 -25.00%
3/8? stud 45 35 -28.57%
7/16? stud 71 56 -26.79%
1/2? stud 108 84 -28.57%
9/16? stud 156 122 -27.87%
5/8? stud 214 167 -28.14%

...that if I coated the threads with moly that spoke wind-up would not
occur until spoke tension was significantly higher?

http://www.arrowprecision.co.uk/details.php?id=62774
...would doubtless do a half-dozen wheel, and is only a couple of
quid.

I think this could be empirically assessed but would require a
tensiometer, and two sets of spokes/ nipples (I suggest the friction
in the threads might differ after bringing to tension once and bedding
the threads)

Any thoughts?

Thomas Hood

Dear Thomas,

Just tape a piece of paper to a spoke to serve as a flag.

When the spoke starts to twist, the flag will start to turn.

Count turns of the spoke wrench on a couple of spokes and see if
there's any significant difference.

Cheers,

Carl Fogel

Quoted message said:

Just tape a piece of paper to a spoke to serve as a flag.

When the spoke starts to twist, the flag will start to turn.

Count turns of the spoke wrench on a couple of spokes and see if
there's any significant difference.

Hi Carl,

I know how to observe wind-up, having done precisely what you (with
Post-Its) before. As far as making a quantative assessment goes,
(rethinking what I wrote earlier) I could, of course, just lube one
half of the wheel with 30w oil and the other with moly. Assuming the
moly outperforms the motor oil I could count how many fractions of
turns the moly'd spokes make it without wind-up, beyond the point
where the oiled spokes are binding.

Tom

On 20 May 2007 11:38:24 -0700, Thomas Hood <[email hidden]>

may have said:

Dear All,

I am about to build a set of wheels and it occurs to me that a
molybdenum disulfide based lube (rather than 30w engine oil) on the
threads might reduce the problem of spoke wind-up greatly.

Is it fair to extrapolate from here:
http://www.arp-bolts.com/Catalog/Catalog.PDF/ARPCatalog_0024.pdf

Thread size, Torque w/ 30W motor oil, with moly, (my calculated % less
torque for moly)
5/16? stud 25 20 -25.00%
3/8? stud 45 35 -28.57%
7/16? stud 71 56 -26.79%
1/2? stud 108 84 -28.57%
9/16? stud 156 122 -27.87%
5/8? stud 214 167 -28.14%

...that if I coated the threads with moly that spoke wind-up would not
occur until spoke tension was significantly higher?

http://www.arrowprecision.co.uk/details.php?id=62774
...would doubtless do a half-dozen wheel, and is only a couple of
quid.

I think this could be empirically assessed but would require a
tensiometer, and two sets of spokes/ nipples (I suggest the friction
in the threads might differ after bringing to tension once and bedding
the threads)

Any thoughts?

Swatting gnats with a tire iron.

MoS2 has little or no advantage over ordinary oil in this instance.

If the threads are clean, properly rolled/cut, and lubed with motor
oil or other suitable substance (not WD40 or penetrant), spoke wind-up
is simply not an issue.

Use brass nipples.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

moly is used to reduce wear between flat meshed gear surfaces? or is
that a different compound?
thinned synthetic oils or the top oil off settled red finish line are
slippery.
web searchs produce volumes of exotic synth oils qualified with
numbers: a slipprier synth is probbbbaly there somewhere.
given the small thread/contact area leading up to the desired torque
levels, you might not expect too much qaul or quant difference between
slippery lubes

Thomas Hood said:

Dear All,

I am about to build a set of wheels and it occurs to me that a
molybdenum disulfide based lube (rather than 30w engine oil) on the
threads might reduce the problem of spoke wind-up greatly.

Quoted message said:

...that if I coated the threads with moly that spoke wind-up would not
occur until spoke tension was significantly higher?

http://www.arrowprecision.co.uk/details.php?id=62774
...would doubtless do a half-dozen wheel, and is only a couple of
quid.

I think this could be empirically assessed but would require a
tensiometer, and two sets of spokes/ nipples (I suggest the friction
in the threads might differ after bringing to tension once and bedding
the threads)

Any thoughts?

Thomas Hood

wheelbuilding will be more fun without MoS2 stains everywhere!
--
/Marten

info(apestaartje)m-gineering(punt)nl

very slippery stuff

http://www.infiniteuse.com/

the background i have on this, which is disputed, is the spoke path to
the hub out of the nipple end, at desired torque levels, binds the
threading and then prevents spoke loosening with increased holding
capacity

builders including Brandt recommend oil for nipple thread lube. Oil
evaporates, increasing holding capacity.

I use linseed oil to increase corrosion resistance and continued
lubrication as it doesn't evap it polymerizes then increasing holding
capacity

moly would continue lubrication when dry?

all potential nipple thread lubes continuing lubrication would be a
system's negative

Quoted post said:

builders including Brandt recommend oil for nipple thread lube. Oil
evaporates, increasing holding capacity.

Woah there! Engine oil doesn't evaporate at a significant rate. As I
understand it a bolt torqued to X ft lbs will produce a clamping force
inversely proportional to the friction in its threads. I.e. a second
bolt with lower friction threads would produce a greater clamping
force when torqued to X ft lbs, but would be resistant to loosening to
exactly the same degree.

Quoted message said:

I use linseed oil to increase corrosion resistance and continued
lubrication as it doesn't evap it polymerizes then increasing holding
capacity

We're back to 'spoke prep'.

Quoted message said:

moly would continue lubrication when dry?

all potential nipple thread lubes continuing lubrication would be a
system's negative

I don't think this is true.

If moly does reduce significantly the thread friction, then I imagine
it would be of utility when replacing spokes in today's low spoke-
count wheels. They're an absolute bugger to true as the tension is so
high -- they just wind-up unless you press the rim to one side.

Tom

P.S. I'm building DT 1.8/2.0 with brass nipples, 36 3x on a DRC
eyeleted and socketed box section rim, laced to Shimano Dura Ace 7700
hub, before anyone reprimands me for choosing innapropriate equipment

"Thomas Hood" <[email hidden]> wrote in message
news:[email hidden]...
Dear All,

I am about to build a set of wheels and it occurs to me that a
molybdenum disulfide based lube (rather than 30w engine oil) on the
threads might reduce the problem of spoke wind-up greatly.

Is it fair to extrapolate from here:
http://www.arp-bolts.com/Catalog/Catalog.PDF/ARPCatalog_0024.pdf

Thread size, Torque w/ 30W motor oil, with moly, (my calculated % less
torque for moly)
5/16? stud 25 20 -25.00%
3/8? stud 45 35 -28.57%
7/16? stud 71 56 -26.79%
1/2? stud 108 84 -28.57%
9/16? stud 156 122 -27.87%
5/8? stud 214 167 -28.14%

....that if I coated the threads with moly that spoke wind-up would not
occur until spoke tension was significantly higher?

http://www.arrowprecision.co.uk/details.php?id=62774
....would doubtless do a half-dozen wheel, and is only a couple of
quid.

I think this could be empirically assessed but would require a
tensiometer, and two sets of spokes/ nipples (I suggest the friction
in the threads might differ after bringing to tension once and bedding
the threads)

Any thoughts?

Thomas Hood

Molybdenum disulfide has an extremely low coefficient of friction which is
very effecting in reducing sliding friction such as would be found in
threads.

Motor oil contains long chain polymers that create a strong boundry layer
to prevent metal to metal contact at elevated temperatures.

Liquids can be compressed under extreme pressure. Since motor oil in a
liquid it probably wont compress under the pressure developed in the spoke
threads but it can be squeezed out. Most motor oils contain some solid
metallic compounds usually zinc or nickel based but not enough to
significantly effect the low temperatures that would result from
tightening spoke nipples.

Molybdenum disulfide is a solid and is usually available in a powder or a
liquid based slurry.

It will probably provide more lubrication than motor oil but it might also
allow the spoke nipples to work loose over time, I don't know.

Older Porsche 911 and 912 transmissions used molybdenum disulfide to
improve shifting. There's a lot of sliding friction on the gear shafts in
an car's transmission.

A fellow mechanic put one of the tubes of Porsche molybdenum disulfide
into his recently overhauled 1956 Porsche 356A transmission and it
wouldn't shift afterwards. It turned out that the older synchros required
more friction to shift than the later transmissions. He had to tear the
transmission apart and have all the parts passivated to get rid on the
molybdenum disulfide.

Moral: If the spokes start coming loose after using molybdenum disulfide
you will probably have to replace at least the spoke nipples.

Chas.

Thomas Hood said:

I am about to build a set of wheels and it occurs to me that a
molybdenum disulfide based lube (rather than 30w engine oil) on the
threads might reduce the problem of spoke wind-up greatly.

Quoted message said:

Is it fair to extrapolate from here:

http://www.arp-bolts.com/Catalog/Catalog.PDF/ARPCatalog_0024.pdf

Quoted message said:

I think this could be empirically assessed but would require a
tensiometer, and two sets of spokes/ nipples (I suggest the friction
in the threads might differ after bringing to tension once and
bedding the threads)

As Carl suggested, lube some of the spokes with motor oil and some
with your favorite elixir. By use of tape flags on spokes measure the
wind-up you get for each in difference and consistency.

The whole problem seems to be theoretical, while wheel building is a
practical exercise that has been done for a long time without
tensiometers and molybdenum disulfide oil.

Jobst Brandt

as a linseed user, oil is garbage thinking for spokes. oil washes out
and evaps-remember we're not speaking of a can of oil here.
linseed is not spoke prep. nada
systems using designed in friction are altered with use of hi tech
slippery lubes
i hear some wheel people use jigs to hold one spoke wheels and their
nerves steady

Quoted post said:

as a linseed user, oil is garbage thinking for spokes. oil washes out
and evaps-remember we're not speaking of a can of oil here.
linseed is not spoke prep. nada
systems using designed in friction are altered with use of hi tech
slippery lubes
i hear some wheel people use jigs to hold one spoke wheels and their
nerves steady

forgot-i remember moly, this is some time ago so moly now may not be
moly then, is granular and maybe effective when it drys for spoke
threadlock. the idea was two gear surfaces mesh on the moly particles
not the gear surfaces.
i recommend CRC rubber belt compound for rim brake areas for the same
effect: braking occurs within the brake prep not rim or pad
effectively reducing wear while increasing brake effectiveness 2x+
synthetic trans oils may have replaced moly for differential and
transmission wear prevention. if you try switching to synth from dino,
you know why: synth is slick in the ol rock crusher.

Quoted message said:

As Carl suggested, lube some of the spokes with motor oil and some
with your favorite elixir. By use of tape flags on spokes measure the
wind-up you get for each in difference and consistency.

The whole problem seems to be theoretical, while wheel building is a
practical exercise that has been done for a long time without
tensiometers and molybdenum disulfide oil.

Jobst Brandt

See this gallery for photos of my experiment: http://tinyurl.com/ypxccx

The MoS2 paste ( http://tinyurl.com/ytncls ) made a dramatic
difference: Using 30W motor oil the spoke wound-up significantly (180
degrees) beyond 160lbs of tension, with moly I couldn't get it to wind-
up. You can see I loaded the spoke as heavily as I could -- 375lbs!

The wheel in the photo I built up with 30w oil and it's quite a sturdy
rim (550gms IIRC). I built it with flags and as I built it to maximum
tension I found the degree of wind-up much greater than expected. I
also found that my 'feel' wasn't always correct -- maybe if I built
wheels more often it might. When approaching maximum tension the
degree of wind-up was significant (on some spokes approaching 180
degrees) and I believe without wind-up the wheel could have been built
more easily and quickly.

I imagine this might make machine built wheels more consistently
tensioned and with less regression in the process. It also should be
useful for mechanics whose customers insist on bladed spokes and the
like.

Purely out of interest I'd like to see if a wheel can be built to
maximum tension with 1.8/1.5mm DT revolution spokes http://tinyurl.com/7h56o,
and will do so if I can find someone that sells the things in the UK
-- all shops I've tried only have 2.0/1.5mm.

If anyone has some moly paste lying around around give it a shot and
tell me what you think.

Tom

Thomas Hood said:

Quoted message said:

As Carl suggested, lube some of the spokes with motor oil and some
with your favorite elixir. By use of tape flags on spokes measure
the wind-up you get for each in difference and consistency.

Quoted message said:

Quoted message said:

The whole problem seems to be theoretical, while wheel building is
a practical exercise that has been done for a long time without
tensiometers and molybdenum disulfide oil.

Quoted message said:

See this gallery for photos of my experiment:

http://tinyurl.com/ypxccx

Quoted message said:

The MoS2 paste ( http://tinyurl.com/ytncls ) made a dramatic
difference: Using 30W motor oil the spoke wound-up significantly
(180 degrees) beyond 160lbs of tension, with moly I couldn't get it
to wind- up. You can see I loaded the spoke as heavily as I could
-- 375lbs!

Quoted message said:

The wheel in the photo I built up with 30w oil and it's quite a
sturdy rim (550gms IIRC). I built it with flags and as I built it
to maximum tension I found the degree of wind-up much greater than
expected. I also found that my 'feel' wasn't always correct --
maybe if I built wheels more often it might. When approaching
maximum tension the degree of wind-up was significant (on some
spokes approaching 180 degrees) and I believe without wind-up the
wheel could have been built more easily and quickly.

Quoted message said:

I imagine this might make machine built wheels more consistently
tensioned and with less regression in the process. It also should
be useful for mechanics whose customers insist on bladed spokes and
the like.

I'm glad to see that there is a way to make tight 1.5mm diameter
spokes, especially with 2mm diameter ends that generate more friction
torque than more balanced spokes would. On the other hand, I see no
reason to use such thin spokes, the weight savings being insignificant
with no aerodynamic advantage. I suppose flat spokes are the ones
that gain benefit from reduced thread torque if you need flat spokes.

Quoted message said:

Purely out of interest I'd like to see if a wheel can be built to
maximum tension with 1.8/1.5mm DT revolution spokes
http://tinyurl.com/7h56o, and will do so if I can find someone that
sells the things in the UK -- all shops I've tried only have
2.0/1.5mm.

Quoted message said:

If anyone has some moly paste lying around around give it a shot and
tell me what you think.

As I said, I've not needed more lubricant than 30W motor oil or for
that matter 90W hypoid gear oil that works well too. Windup, as long
as it isn't great enough to break spokes, is not a problem, the manual
wheel builder being able to relax that before going to the next spoke.

The problem is for machine building where twist is not predictable.
In those machined, a spoke unloading piston should press inward at the
spoke to be adjusted to assure that there is NO windup.

Jobst Brandt

Quoted message said:

Thomas Hood said:

Quoted message said:

As Carl suggested, lube some of the spokes with motor oil and some
with your favorite elixir. By use of tape flags on spokes measure
the wind-up you get for each in difference and consistency.

Quoted message said:

Quoted message said:

The whole problem seems to be theoretical, while wheel building is
a practical exercise that has been done for a long time without
tensiometers and molybdenum disulfide oil.

Quoted message said:

See this gallery for photos of my experiment:

http://tinyurl.com/ypxccx

Quoted message said:

The MoS2 paste ( http://tinyurl.com/ytncls ) made a dramatic
difference: Using 30W motor oil the spoke wound-up significantly
(180 degrees) beyond 160lbs of tension, with moly I couldn't get it
to wind- up. You can see I loaded the spoke as heavily as I could
-- 375lbs!

Quoted message said:

The wheel in the photo I built up with 30w oil and it's quite a
sturdy rim (550gms IIRC). I built it with flags and as I built it
to maximum tension I found the degree of wind-up much greater than
expected. I also found that my 'feel' wasn't always correct --
maybe if I built wheels more often it might. When approaching
maximum tension the degree of wind-up was significant (on some
spokes approaching 180 degrees) and I believe without wind-up the
wheel could have been built more easily and quickly.

Quoted message said:

I imagine this might make machine built wheels more consistently
tensioned and with less regression in the process. It also should
be useful for mechanics whose customers insist on bladed spokes and
the like.

I'm glad to see that there is a way to make tight 1.5mm diameter
spokes, especially with 2mm diameter ends that generate more friction
torque than more balanced spokes would. On the other hand, I see no
reason to use such thin spokes, the weight savings being insignificant
with no aerodynamic advantage.

what about the fatigue advantage? you yourself state that the increased
elasticity of butted spokes makes them more fatigue resistant. and
sapim's fatigue tables support that position.

Quoted message said:

I suppose flat spokes are the ones
that gain benefit from reduced thread torque if you need flat spokes.

Quoted message said:

Purely out of interest I'd like to see if a wheel can be built to
maximum tension with 1.8/1.5mm DT revolution spokes
http://tinyurl.com/7h56o, and will do so if I can find someone that
sells the things in the UK -- all shops I've tried only have
2.0/1.5mm.

Quoted message said:

If anyone has some moly paste lying around around give it a shot and
tell me what you think.

As I said, I've not needed more lubricant than 30W motor oil or for
that matter 90W hypoid gear oil that works well too. Windup, as long
as it isn't great enough to break spokes, is not a problem, the manual
wheel builder being able to relax that before going to the next spoke.

The problem is for machine building where twist is not predictable.
In those machined, a spoke unloading piston should press inward at the
spoke to be adjusted to assure that there is NO windup.

Jobst Brandt

In article <[email hidden]>,

Thomas Hood said:

The MoS2 paste ( http://tinyurl.com/ytncls ) made a dramatic
difference: Using 30W motor oil the spoke wound-up significantly (180
degrees) beyond 160lbs of tension, with moly I couldn't get it to wind-
up. You can see I loaded the spoke as heavily as I could -- 375lbs!

The wheel in the photo I built up with 30w oil and it's quite a sturdy
rim (550gms IIRC). I built it with flags and as I built it to maximum
tension I found the degree of wind-up much greater than expected. I
also found that my 'feel' wasn't always correct -- maybe if I built
wheels more often it might. When approaching maximum tension the
degree of wind-up was significant (on some spokes approaching 180
degrees) and I believe without wind-up the wheel could have been built
more easily and quickly.

Did you consider that while MoS2 paste decreases thread friction and
makes it easier to tension spokes, it may also cause spokes to unscrew
in use? Also, couldn't one could inadvertently over tension spokes
without using a tensiometer? Is there a galvanic corrosion issue with
MoS2 on stainless steel spokes and brass or aluminum nipples?

Larry Dickman said:

Quoted message said:

The MoS2 paste ( http://tinyurl.com/ytncls ) made a dramatic
difference: Using 30W motor oil the spoke wound-up significantly
(180 degrees) beyond 160lbs of tension, with moly I couldn't get it
to wind- up. You can see I loaded the spoke as heavily as I could
-- 375lbs!

Quoted message said:

Quoted message said:

The wheel in the photo I built up with 30w oil and it's quite a
sturdy rim (550gms IIRC). I built it with flags and as I built it
to maximum tension I found the degree of wind-up much greater than
expected. I also found that my 'feel' wasn't always correct --
maybe if I built wheels more often it might. When approaching
maximum tension the degree of wind-up was significant (on some
spokes approaching 180 degrees) and I believe without wind-up the
wheel could have been built more easily and quickly.

Quoted message said:

Did you consider that while MoS2 paste decreases thread friction and
makes it easier to tension spokes, it may also cause spokes to
unscrew in use? Also, couldn't one could inadvertently over tension
spokes without using a tensiometer? Is there a galvanic corrosion
issue with MoS2 on stainless steel spokes and brass or aluminum
nipples?

Have you built any wheels? Friction that keeps spoke nipples from
rotating comes almost entirely from the interface with the rim, a
diameter many times that of the thread. Quit posting specious
bugaboos.

Jobst Brandt

Quoted message said:

Larry Dickman said:

Quoted message said:

The MoS2 paste (http://tinyurl.com/ytncls) made a dramatic
difference: Using 30W motor oil the spoke wound-up significantly
(180 degrees) beyond 160lbs of tension, with moly I couldn't get it
to wind- up. You can see I loaded the spoke as heavily as I could
-- 375lbs!
The wheel in the photo I built up with 30w oil and it's quite a
sturdy rim (550gms IIRC). I built it with flags and as I built it
to maximum tension I found the degree of wind-up much greater than
expected. I also found that my 'feel' wasn't always correct --
maybe if I built wheels more often it might. When approaching
maximum tension the degree of wind-up was significant (on some
spokes approaching 180 degrees) and I believe without wind-up the
wheel could have been built more easily and quickly.

Did you consider that while MoS2 paste decreases thread friction and
makes it easier to tension spokes, it may also cause spokes to
unscrew in use? Also, couldn't one could inadvertently over tension
spokes without using a tensiometer? Is there a galvanic corrosion
issue with MoS2 on stainless steel spokes and brass or aluminum
nipples?

Have you built any wheels? Friction that keeps spoke nipples from
rotating comes almost entirely from the interface with the rim, a
diameter many times that of the thread. Quit posting specious
bugaboos.

That's not entirely true; if it were, threadlock compound would never
be useful.

Have *you* built and used any 130mm OLD, 8/9/10 sp rear wheels using
rims that are available in the 21st century?

Ozark Bicycle said:

Quoted message said:

Quoted message said:

> The MoS2 paste (http://tinyurl.com/ytncls) made a dramatic
> difference: Using 30W motor oil the spoke wound-up significantly
> (180 degrees) beyond 160lbs of tension, with moly I couldn't get it
> to wind- up. You can see I loaded the spoke as heavily as I could
> -- 375lbs!

Quoted message said:

Quoted message said:

Quoted message said:

> The wheel in the photo I built up with 30w oil and it's quite a
> sturdy rim (550gms IIRC). I built it with flags and as I built it
> to maximum tension I found the degree of wind-up much greater than
> expected. I also found that my 'feel' wasn't always correct --
> maybe if I built wheels more often it might. When approaching
> maximum tension the degree of wind-up was significant (on some
> spokes approaching 180 degrees) and I believe without wind-up the
> wheel could have been built more easily and quickly.

Quoted message said:

Quoted message said:

Quoted message said:

Did you consider that while MoS2 paste decreases thread friction and
makes it easier to tension spokes, it may also cause spokes to
unscrew in use? Also, couldn't one could inadvertently over tension
spokes without using a tensiometer? Is there a galvanic corrosion
issue with MoS2 on stainless steel spokes and brass or aluminum
nipples?

Quoted message said:

Quoted message said:

Have you built any wheels? Friction that keeps spoke nipples from
rotating comes almost entirely from the interface with the rim, a
diameter many times that of the thread. Quit posting specious
bugaboos.

Quoted message said:

That's not entirely true; if it were, threadlock compound would never
be useful.

I think you don't understand why thread lock is used. This stuff is
for wheels whose spokes become slack while riding normally because the
spokes cannot be tightened properly with rims that crack when
tensioned properly. At that moment there is no friction between spoke
nipple and rim.

Quoted message said:

Have *you* built and used any 130mm OLD, 8/9/10 sp rear wheels using
rims that are available in the 21st century?

Are you an apologist for the rims of diminished capacity that are
offered these days? I don't use the "new and improved" rims to which
you allude.

Jobst Brandt