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WMW
- in the industry
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by WMW on Sat Apr 05, 2014 5:10 pm
Marin wrote:Yes, otherwise they wouldn't touch at all. The idea is to prevent a single spoke from going completely slack when unloaded by making it share stresses with the crossing spoke.
Doesn't actually work. After adjusting the spoke line and stress relieving the spokes should not be pushing sideways with any force. And even if they were limp threads, the side force would only add a couple % to the max load before they'd go slack.
formerly rruff...
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Marin
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by Marin on Mon Apr 07, 2014 7:13 am
Can you explain again why? Lacing the spokes / crossing over&under has been recommended for 2- and 3x builds practically since these patterns have been invented, and I and most other builders have always done it that way, so the info that this is a problem is news to me.
What do you think the negative effects could be?
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prowheelbuilder
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- Location: Cumming GA
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by prowheelbuilder on Fri Apr 18, 2014 12:21 am
The over under pattern helps lock the spokes to help prevent sheer under torsion. However in the case of your front wheel there are two factors that have led to the extreme angles you are seeing. The first issue is the 20 hole drilling and the second is the small flange. Normally a two cross pattern with a 20 hole hub on a 700c rim would have been ok. However with the reduced flange diameter the holes on the hubs come closer together causing the extreme angle you see.
All that being said there is little need to be concerned as the yield strength of the spoke has only been exceeded once at this point and as long as the wheel has been properly tensioned and stress relieved there is very little reason to expect work hardening do to excessive movement.
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Marin
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by Marin on Sun Apr 20, 2014 8:23 am
The angles aren't even that extreme, they are exaggerated by the photograph. I'd build the wheel the same way again.