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  1. #3051
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    Quote Originally Posted by kindacreeky View Post
    Appreciate the advice. This is my first wheel build, and I am just learning about this science. I am an engineer, and am trying to understand the physics of this. With a 2X pattern, the spoke pulls more outward on the hub flange. With the 3X, the pull is more tangential. I can see why CK would specify the 3X only pattern, as that would stress the hub flange less (more meat in hub when pulling tangential than more straight out). Can anyone explain why it would be preferable to put the 2x on the Drive side of the rear?
    I don't think it would meaningfully affect the performance. You will shave a handful of grams with the shorter spokes and very very slightly increase the bracing angle on that side. A 2x wheel is very very slightly more radially and laterally rigid than a 3X wheel. I don't know of anyone having looked at mixed pattern wheels.

    Quote Originally Posted by kindacreeky View Post
    Also, I have read in this forum that 2x gives a more rigid build. Is this true? On my Tallboy, with FS, I am mainly interested in improved lateral rigidity and more accurate tracking out of this wheel, but of course want to keep weight down too.

    Last night, I checked some wheels built for me by Dave's Wheels at Speedreams.com. He built a 26er wheel for my Blur and he put 2x on the low tension sides front and rear; and 3x on the high tension side. So I was going by that example.
    3x all around is probably the best bet. Anything else will be just for fun and not meaningfully affect performance.
    I did 3x-1x heads out on my SS front wheel just for fun.
    Quote Originally Posted by pvd
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  2. #3052
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    Shipping time

    Hello all, I bought some LB rims finally! I have all my components and I'm just waiting for the rims to be made / shipped. For those that have received their rims I the last week or so when did you place your order? I ordered 12k matte rims on December 31. I am lacing them to DT 350 hubs with Sapim Laser spokes 3x, fwiw. I am so freaking excited!

  3. #3053
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    Quote Originally Posted by Trackdawson View Post
    Hello all, I bought some LB rims finally! I have all my components and I'm just waiting for the rims to be made / shipped. For those that have received their rims I the last week or so when did you place your order? I ordered 12k matte rims on December 31. I am lacing them to DT 350 hubs with Sapim Laser spokes 3x, fwiw. I am so freaking excited!
    I received mine on Jan. 8. I ordered on Dec. 17. They responded on Dec. 18. So about 3 weeks. Decent, from half way around the world.
    Kindacreeky,
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  4. #3054
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    According to Jobst Brandt 3x is stronger than 2x because of more bracing of the spokes. In my estimation it would be stiffer too because of more bracing by the crosses.
    Full rigid SS, Hardtail SS, Hardtail Geared, Full Suspension Geared.

  5. #3055
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    Quote Originally Posted by yourdaguy View Post
    According to Jobst Brandt 3x is stronger than 2x because of more bracing of the spokes. In my estimation it would be stiffer too because of more bracing by the crosses.
    Appreciate all the advice on this discussion. I decided to go with 3x all around.

    Anybody have problems with using alloy nipples instead of brass? Any special procedures or cautions? I have read the recommendations on lubing the nipple seat against the carbon rim.

    Any special spoke thread lube or compound that you guys would advise me using? I read Sheldon Brown cautioned to not use lube on the low tension side as might tend to back off. Do I need to go with loc-tite on that side?
    Kindacreeky,
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  6. #3056
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    Quote Originally Posted by reamer41 View Post
    I measured the ERD. Form the bottom of the slot in the nipple I came up with 606mm. Measured in several spots, both rims. No variance.
    This is my very first wheelbuild so I don't yet have nipples laying around here what length would this add (per side) to the ERD that I will measure from the rim nipple hole's inner edge (the edge which touches the nipple head)?

    I'm guessing 2mm, but since the nipple has a slot, it's probably less. Weird that DT Swiss doesn't publish this, but then, one should just get the nipple and measure it themselves.

    I'm going to measure the ERD now, will report back later.

    Thanks for all the suggestion guys, very valuable.

    EDIT: ah, did some googling and looks like to obtain the accurate ERD, I definitely need 2 nipples and 2 spokes, or at least those 2 nipples and a wire, or something like that. So I'll get the nipples/spokes first I think. (Found also this thing but huh, not sure if that's really needed.)
    Last edited by ypocat; 01-11-2013 at 01:36 PM.

  7. #3057
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    Thanks for the reply about the shipping time. Where in TN are you? I'm down in Oxford MS. As far as lubing the nipple seats, I am planning on using Dumond liquid grease. I am hoping the plasticizers in the grease can allow a better lubrication as well as a barrier to all that galvanic corrosion between my alu nipps and cf rim Any thoughts for or against would be welcome.

  8. #3058
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    Lube all the nipples both where they contact the rim and lube the spoke threads. Most people just dip all the spokes before they start. Alloy nipples are fine, In 5 years or so they might start to crack but by then you might want to rebuild it with new nipples. Brass nipples weigh something like 3 times a much but basically last forever. ERD is measured using a spoke and nipples, but you don't subtract for the nipple length when calculating spoke length. This is because if you did everything (calculations) correctly the end of the spoke will be in or right at the base of the nipple.
    Full rigid SS, Hardtail SS, Hardtail Geared, Full Suspension Geared.

  9. #3059
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    Quote Originally Posted by kindacreeky View Post
    CK states max of 120 kgf, and wants all hubs laced 3x.
    Interesting that CK says that, since Enve rims are molded to be 2X and are available with CK hubs. I'm curious because I want to build up a set of SS wheels with CK hubs and would rather lace them 2X to keep the spoke angle at the rim from being too acute.

  10. #3060
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    Quote Originally Posted by yourdaguy View Post
    In my estimation it would be stiffer too because of more bracing by the crosses.
    The lower the cross pattern, the stiffer the wheel radially & laterally. This has been shown both by FEA and direct measurements.
    Torsionally the opposite is true.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  11. #3061
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    Quote Originally Posted by Trackdawson View Post
    Thanks for the reply about the shipping time. Where in TN are you? I'm down in Oxford MS. As far as lubing the nipple seats, I am planning on using Dumond liquid grease. I am hoping the plasticizers in the grease can allow a better lubrication as well as a barrier to all that galvanic corrosion between my alu nipps and cf rim Any thoughts for or against would be welcome.
    located in Nashville area.

    OK, now I am wondering about corrosion potential against carbon rim (with alloy nips). Did not consider that. I would have thought that the epoxy resin would encapsulate the carbon so well that there would just not be enough to cause a reaction. Any experience out there?
    Kindacreeky,
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  12. #3062
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    Quote Originally Posted by kindacreeky View Post
    located in Nashville area.

    OK, now I am wondering about corrosion potential against carbon rim (with alloy nips). Did not consider that. I would have thought that the epoxy resin would encapsulate the carbon so well that there would just not be enough to cause a reaction. Any experience out there?
    Since there is not one single report on this forum that I have seen of an issue related to corrosion using aluminum nipples with carbon rims with hundreds of people using that combo on this forum alone, I don't think it is concern. One guy theorized that it is a major issue, but not one real world report that I could find supports it....so I am building with aluminum.

  13. #3063
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    Quote Originally Posted by Haymarket View Post
    Since there is not one single report on this forum that I have seen of an issue related to corrosion using aluminum nipples with carbon rims with hundreds of people using that combo on this forum alone, I don't think it is concern. One guy theorized that it is a major issue, but not one real world report that I could find supports it....so I am building with aluminum.
    Here is my summary of the nipple corrosion posts:

    Steel spokes + brass nipples + aluminum rims = aluminum rims corrode

    Steel spokes + aluminum nipples + aluminum rims = aluminum nipples corrode

    Steel spokes + brass nipples + carbon rims = virtually nothing corrodes

    Steel spokes + aluminum nipples + carbon rims = aluminum nipples corrode

    Aluminum nipples became popular because (among other reasons) they absorbed the corrosion instead of the rim. Rims are costly to replace.

    With carbon rims, the only benefit of aluminum nipples is weight as there is no reason to protect the rim from corrosion.

    It is my opinion that if you ride it wet conditions you should use brass nipples with carbon rims.

  14. #3064
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    Quote Originally Posted by Adroit Rider View Post
    Here is my summary of the nipple corrosion posts:

    Steel spokes + brass nipples + aluminum rims = aluminum rims corrode

    Steel spokes + aluminum nipples + aluminum rims = aluminum nipples corrode

    Steel spokes + brass nipples + carbon rims = virtually nothing corrodes

    Steel spokes + aluminum nipples + carbon rims = aluminum nipples corrode

    Aluminum nipples became popular because (among other reasons) they absorbed the corrosion instead of the rim. Rims are costly to replace.

    With carbon rims, the only benefit of aluminum nipples is weight as there is no reason to protect the rim from corrosion.

    It is my opinion that if you ride it wet conditions you should use brass nipples with carbon rims.
    Has anybody on here had an issue with corrosion in building carbon rims with aluminum nipples? I know what you say and am sure it is true, but is there a real world effect here? Lots and lots of rims built that way, and I just hadn't seen any issues reported from that. Have there been any?

  15. #3065
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    Quote Originally Posted by Haymarket View Post
    Has anybody on here had an issue with corrosion in building carbon rims with aluminum nipples? I know what you say and am sure it is true, but is there a real world effect here? Lots and lots of rims built that way, and I just hadn't seen any issues reported from that. Have there been any?
    No, the corrosion has nothing to do with the rims but everything to do with the nipples and spokes.

    Here is your worst case scenario:

    Many miles from now your spokes detention and weaken. One spoke breaks while on a 50 mile epic and your wheel goes out of true. You try and fix the wobble by adjusting the tension on surrounding spokes but the nipples have corroded and will not turn. You ride the wobbly wheel back home and have a new spoke installed or you have the hub and possibly rim rebuilt.

  16. #3066
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    Quote Originally Posted by Adroit Rider View Post
    No, the corrosion has nothing to do with the rims but everything to do with the nipples and spokes.

    Here is your worst case scenario:

    Many miles from now your spokes detention and weaken. One spoke breaks while on a 50 mile epic and your wheel goes out of true. You try and fix the wobble by adjusting the tension on surrounding spokes but the nipples have corroded and will not turn. You ride the wobbly wheel back home and have a new spoke installed or you have the hub and possibly rim rebuilt.
    Actually, if you're talking about the rim/nipple interface (we are) the spokes are irrelevant.
    I think his point is still valid.
    Are there any actual reports/experiences/photos of corrosion problems?
    Last edited by meltingfeather; 01-12-2013 at 07:36 AM.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  17. #3067
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    No actual reports I am aware of, but galvanic corrosion strength between carbon rims and aluminum nipples would be about 2 orders of magnitude greater than aluminum rims and nipples. Also, carbon rims are stiffer than aluminum and the nipples would tend to flex more in carbon rims and aluminum is subject to stress cracks from flexing.
    I built all my carbon wheels with aluminum nipples, but I fully expect to have some issues and probably have to rebuild with new nipples 5 or more years down the road. If it becomes a problem, I will rebuild with brass nipples. I just don't see aluminum nipples lasting forever between stainless spokes and carbon rims. And the idea of the aluminum nipples corroding to the stainless spokes is real I have seen this on older aluminum rim nipple combinations with stainless spokes. When you try to turn the nipple, it just breaks off and kind of crumbles. The wheels in question were 5 year old Stans with probably over 6000 dirt (and some winter street rides in Baltimore) miles and lots of washings.
    Full rigid SS, Hardtail SS, Hardtail Geared, Full Suspension Geared.

  18. #3068
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    Quote Originally Posted by kindacreeky View Post
    Last night, I checked some wheels built for me by Dave's Wheels at Speedreams.com. He built a 26er wheel for my Blur and he put 2x on the low tension sides front and rear; and 3x on the high tension side. So I was going by that example.
    I checked again this morning. The Dave's Wheels only uses the 2x on the drive side of the front. The rear uses 3x both sides. Sorry for mistake.
    Kindacreeky,
    Tennessee Singletrac Sculpter

  19. #3069
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    Quote Originally Posted by Haymarket View Post
    Has anybody on here had an issue with corrosion in building carbon rims with aluminum nipples? I know what you say and am sure it is true, but is there a real world effect here? Lots and lots of rims built that way, and I just hadn't seen any issues reported from that. Have there been any?
    I haven't. On my road bike, I have a set of carbon wheels with aluminum nipples that have been used daily for 5 years. I ride them in the rain, salt, grime, etc. There is ZERO corrosion.

    I have another set of carbon tubulars that have been used daily for 3 years, again, zero corrosion.

    Most of the people I ride with have carbon wheels I haven't heard or seen a single instance of corrosion. IMO, it's a non issue

  20. #3070
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    Quote Originally Posted by yourdaguy View Post
    No actual reports I am aware of, but galvanic corrosion strength between carbon rims and aluminum nipples would be about 2 orders of magnitude greater than aluminum rims and nipples.
    what do you mean by "strength?"
    do you mean current density?
    where'd you come up with "2 orders of magnitude," which is ~100x?
    run through the math for me, assuming the following galvanic potentials:
    graphite - (+)0.3V
    aluminum alloy - (-)0.9V
    brass - (-)0.4V

    Quote Originally Posted by yourdaguy View Post
    Also, carbon rims are stiffer than aluminum and the nipples would tend to flex more in carbon rims and aluminum is subject to stress cracks from flexing.
    and if a leprechaun bangs a unicorn under a blue moon it will rain gold. so?

    Quote Originally Posted by yourdaguy View Post
    I built all my carbon wheels with aluminum nipples, but I fully expect to have some issues and probably have to rebuild with new nipples 5 or more years down the road. If it becomes a problem, I will rebuild with brass nipples. I just don't see aluminum nipples lasting forever between stainless spokes and carbon rims. And the idea of the aluminum nipples corroding to the stainless spokes is real I have seen this on older aluminum rim nipple combinations with stainless spokes. When you try to turn the nipple, it just breaks off and kind of crumbles. The wheels in question were 5 year old Stans with probably over 6000 dirt (and some winter street rides in Baltimore) miles and lots of washings.
    i just want to see some photos of this doomed combination actually going to hell. i'll keep an eye on my wheels and post macro photos every once in a while.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  21. #3071
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    does anyone have an opinion about d-bike wheels they seem the same as Light Bikes but maybe different spokes.

  22. #3072
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    http://www.sae.org/automag/material/...1-114-8-42.pdf

    Read the Boeing article on page 44 above. It explains the basic problem of galvanic corrosion in wet environments and the fact that Boeing is limiting the use of aluminum in the vicinity of carbon.

    This is a picture of my Sran's Arch front that came on my 2008 Jet9 so I did not build this wheel. The nipples basically locked to the spokes after many hard miles. When I tried to true it the nipple broke and I had to twist so hard that the wrench started to round the flats too. This corrosion would have been because of the stainless spokes in the aluminum nipples. Adding carbon rims should speed up the process. I have to assume that the builder did not use much or enough spoke prep because this should not happen in 5 years on these wheels but I could see it happening in 5 years on a wheel with carbon rims even if it was properly built.

    (Cheap) Chinese Carbon Rims?-2013-01-12_16-47-20_881.jpg

    I don't know where you got your galvanic factors from, but this chart is in the range I have heard in the past even though it is from a boatbuilders site and is in saltwater exposure conditions. I could probably google longer and find another one from another source. I generally ride salty roads in the winter around here so these numbers would be close for 3 months of the year in the midwest. Also, you will notice that Zinc which is the most commonly use sacrificial metal anode is the next thing past aluminum in that direction. So Aluminum is the 2nd best sacrificial anode on the list. By strength, I am referring to the galvanic potential for corrosion between 2 parts. The potential between 2 aluminum parts is almost zero since they have almost the same number. The potential between aluminum and Carbon Fiber is around 2 orders of magnitude as great.

    http://www.boatdesign.net/forums/att...-corrosion.jpg

    I am not against aluminum nipples; all my wheels have them. I am just saying that they might no be the ultimate in reliability when positioned between stainless spokes and carbon rims. I am just pointing this out to people that are asking about it.
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  23. #3073
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    For those wondering the current wait time from Light Bicycle, I ordered a set of Wide UD Matte rims from them on December 20th. Brian confirmed my address the same day and said they'd have to produce the rims in 7-10 days. He informed me that the shipping was 4-5 days. They ended up shipping on January 2nd, and I received 5 days later in PA. Overall happy with the communication and delivery of the rims.

    I had them built up with Sapim spokes, aluminum nips, and nipple washers. The wheel builder (Luke Shirk, from Shirks Bikes) recommended washers on the carbon rims. I swapped out the rims from my Tallboy LTc, so using DT350 rear hub and WTB front. I sealed them with one inch Gorilla tape. The Maxxis Ardent (non tubeless style) seated quickly with compressor. Looking forward to maiden voyage tomorrow at French Creek.
    Last edited by eonicks; 01-12-2013 at 08:44 PM.

  24. #3074
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    Quote Originally Posted by yourdaguy View Post
    http://www.sae.org/automag/material/...1-114-8-42.pdf

    Read the Boeing article on page 44 above. It explains the basic problem of galvanic corrosion in wet environments and the fact that Boeing is limiting the use of aluminum in the vicinity of carbon.

    This is a picture of my Sran's Arch front that came on my 2008 Jet9 so I did not build this wheel. The nipples basically locked to the spokes after many hard miles. When I tried to true it the nipple broke and I had to twist so hard that the wrench started to round the flats too. This corrosion would have been because of the stainless spokes in the aluminum nipples. Adding carbon rims should speed up the process. I have to assume that the builder did not use much or enough spoke prep because this should not happen in 5 years on these wheels but I could see it happening in 5 years on a wheel with carbon rims even if it was properly built.

    Click image for larger version. 

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    I don't know where you got your galvanic factors from, but this chart is in the range I have heard in the past even though it is from a boatbuilders site and is in saltwater exposure conditions. I could probably google longer and find another one from another source. I generally ride salty roads in the winter around here so these numbers would be close for 3 months of the year in the midwest. Also, you will notice that Zinc which is the most commonly use sacrificial metal anode is the next thing past aluminum in that direction. So Aluminum is the 2nd best sacrificial anode on the list. By strength, I am referring to the galvanic potential for corrosion between 2 parts. The potential between 2 aluminum parts is almost zero since they have almost the same number. The potential between aluminum and Carbon Fiber is around 2 orders of magnitude as great.

    http://www.boatdesign.net/forums/att...-corrosion.jpg

    I am not against aluminum nipples; all my wheels have them. I am just saying that they might no be the ultimate in reliability when positioned between stainless spokes and carbon rims. I am just pointing this out to people that are asking about it.
    An arch is aluminum, so I assume there is no example of an issue with aluminum nipples made worse because they were used with a carbon rim. In theory, you argue it is worse, but not one real example is available to indicate a negative affect, and the sample size has gotten fairly large. I don't think anyone is questioning the inherent positives or negatives of aluminum nipples, just questioing whether it is worse to use them with carbon rims. There seem to be no real examples available to support the theory that it is any type of an issue, beyond the weaknesses of aluminum nipples in general.
    Last edited by Haymarket; 01-12-2013 at 06:38 PM.

  25. #3075
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    Quote Originally Posted by yourdaguy View Post
    Read the Boeing article on page 44 above. It explains the basic problem of galvanic corrosion in wet environments and the fact that Boeing is limiting the use of aluminum in the vicinity of carbon.
    This is not a "Boeing" article. Its a very general statement (buried within an article about the use of titanium in coil springs) taken from an Automotive supplier president about materials used in the Dreamliner. Purely anecdotal and not even completely accurate.

    Explain how using an aluminum nipple in a carbon rim is going to speed up corrosion between the nipple and spoke????

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