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Old 08-07-10, 05:41 PM   #1
dooodstevenn
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wheel laces differences? is one stronger than the other?

im looking to build a 32 spoke wheel. and cant decide if i want a 2 cross or 3 cross lacing..are there differences? is the 3 cross stronger than the 2 cross? or is it all just looks? why do people sometimes to a 2 cross in the front and a 3 cross on the rear?
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Old 08-07-10, 05:55 PM   #2
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The more crosses. The more stronger the wheel. 3 is stronger than 2. Front wheels take less abuse than rear wheels.
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Old 08-07-10, 06:03 PM   #3
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Radial and lower cross counts have the advantage of shorter spokes. A bit less metal overall and you have that much lighter a wheel in the end. This is carried to the extreme when building a rear wheel with 2 or 3 cross on the drive side and radial on the other.

The front does not have to withstand forces generated at the hub on a rim brake bike so it can get away with fewer crossings or even a radial pattern. However the rear has to conduct the drive forces out to the rim so a spoke pattern that produces as near to a tengential path for the spoke from the hub is going to produce the least load change in the spoke. For small flange hubs this typically means 2 or 3 cross. For large flange hubs 3 and 4 cross. This assumes typical spoke counts of 28 to 36. Drop to 16 to 24 spokes and the ideal tangential path may only result in one or two crossings.
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Old 08-07-10, 06:23 PM   #4
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thanks for all the info, im going to go with a 3 cross on front and rear, since im heavier that most riders, just to be safe.
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Old 08-07-10, 06:32 PM   #5
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The more crosses. The more stronger the wheel. 3 is stronger than 2. Front wheels take less abuse than rear wheels.
this is not entirely true.

It's all about the exit angle of the spoke from the hub and there's no point in going over 90 degrees.
for instance a 20h wheel will be weaker if you lace it 3x compared to 2x because the spokes can't exit the hub properly.
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Old 08-07-10, 06:38 PM   #6
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this is not entirely true.

It's all about the exit angle of the spoke from the hub and there's no point in going over 90 degrees.
for instance a 20h wheel will be weaker if you lace it 3x compared to 2x because the spokes can't exit the hub properly.
what about a 32?
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Old 08-07-10, 06:43 PM   #7
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Originally Posted by dooodstevenn View Post
what about a 32?
A 32 spoke wheel is at its strongest with a 3X lacing pattern. You really can't get to 4X until you have a 36 spoke wheel.

AEO's point was that for low spoke count wheels reducing the number of crosses works best. But again, 32 spokes are best with a 3X pattern.
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Old 08-07-10, 06:49 PM   #8
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A 32 spoke wheel is at its strongest with a 3X lacing pattern. You really can't get to 4X until you have a 36 spoke wheel.

AEO's point was that for low spoke count wheels reducing the number of crosses works best. But again, 32 spokes are best with a 3X pattern.
oh okay, thanks
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Old 08-08-10, 06:55 AM   #9
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interesting. Is there a formula to figure out how many crosses will generate a 90 degree angle when the spoke exits the hub?
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Old 08-08-10, 08:02 AM   #10
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spocalc lists an ideal crossing
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Old 08-08-10, 02:29 PM   #11
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interesting. Is there a formula to figure out how many crosses will generate a 90 degree angle when the spoke exits the hub?
I use: (360 *4 * (crosses -1)/holes) - asin (ERD - flange diameter)
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Old 08-08-10, 09:18 PM   #12
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If the spokes first cross is pulling past the spoke next to it , the likelihood of it pulling thru the flange is pretty remote,
as the flange is in compression between 2 spokes..
Not in shear forces wanting to pull to the edge.
I've built 4 cross 36,40, and 5 cross 48 spoke wheels,
3 cross in 32 is good in the same regards.

a skilled wheelbuilder can make 32 spoke wheels strong in either pattern, seems like the Pros pull out the 3x32 DB spoke hard anodized box section tubular rims
for Paris- Roubaix,
unless they have a wheel sponsor with something to prove for the marketing campaign.

Last edited by fietsbob; 08-08-10 at 09:26 PM.
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Old 08-08-10, 10:05 PM   #13
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As an experiment I once built a 4x on a Shimano XT rear hub. This required the head down spokes to touch the head of the adjacent spoke as they went from the hub to the rim. The end result is that after a while spokes tended to break where right at this point of contact. Moral to the story: make sure the sweep of the spoke doesn't require it to touch the head of an adjacent spoke. Or, more succinctly, stick with three cross and you'll be fine.

I've built two cross front wheels and rear wheels with three cross on the drive side and two cross on the non-drive that have all held up well (a couple of these wheels are now over 10 years old and still fine!). But if you think about it, the weight you save with a two cross, which is roughly equal to half a spoke on a 32 spoke wheel, is all at the hub. You use a shorter spoke, which means that you use a hole in the hub that is one spot closer to the rim. Well, since weight on a wheel becomes a greater factor as distance from the axle centerline increases (in other words, with increasing radius), this weight savings isn't doing much good. Going two cross on a rear wheel would sacrifice strength while getting almost nothing in return.

So the OP's decision to go three cross seems like a wise choice to me.
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