The wheelbuilding thread

Everything about building wheels, glueing tubs, etc.
Marin
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by Marin

Stiffness and tensile strength are 2 very different parameters.

alcatraz
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by alcatraz

Have you noticed spoke elongation at a given tension is very high in the smaller spokes. That must really play with the limits of the manufacturing processes.

Seems that elongation and elasticity is less of a problem than tensile strength if the spoke companies continue to offer and introduce spokes that elongate several millimeters at normal tension.

I wonder what they do under riding. That must be something else completely.

by Weenie


bm0p700f
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by bm0p700f

Spokes don't elongate by several mm under tension. A CX ray does not even stretch by 1mn at 1300n and after serious stressing.

FilmAt11
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Joined: Sun Jan 09, 2011 2:35 am

by FilmAt11

Before I glue the tubulars, any comments on this build? Is heads-in NDS OK? Thanks!

Rider: 72kg

Hubs: BHS Superlight
Spokes: Sapim Race

Front wheel (20h): 469g
Rear wheel (24h 16:8): 626g

Image

Image

Image

bm0p700f
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by bm0p700f

Heads in stresses the flange more and there is an increased risk of fatigue failure of the flange.

If that's the bhs triplet hub you would have had a stiffer rear wheel with the conventional hub.

You have built it now though.

FilmAt11
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by FilmAt11

Thanks. Which lacing pattern would you recommend with a conventional hub?

alcatraz
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by alcatraz

Shouldn't he do 2x NDS if he's got 3x DS? The spoke tension difference must be extreme with 3x/radial.

If some spokes are as low as 30-40kgf then they might break or loosen by themselves, no?

/a

Marin
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by Marin

The tension difference between 2x and radial is very small, so the relative difference to the DS will be almost the same.

bm0p700f
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by bm0p700f

16:8 is triplet it has to be radial NDS but is should be radial heads out.

With a conventional 24H hub then its 2x both sides. This will be a latterially stiffere wheel. I could work out by how much.

alcatraz spoke loosen off of the wheel is not stiff enough to stop spoke unloading. if the wheel is stiff enough to stop spokes unloading with low tension then there is no problem. look at a wheel in the round rather than at individual characterisitic in isolation.

An example my own set of BORG50C clinchers have miche swr hubs with 49/16mm flange to centre spacing rear. There is not much tension nds even with the ds done up to 1300N. Then there are tubeless tyres fitted to take more tension away. The wheels do not go out of true.

Tension balance is red herring, I don't even consider it. Doing everything to increase it at the expense of other characteristics is not good wheel building in my view. Making the wheels stiff enough to stop spoke unloading is.

Triplet does have some advantages but it really needs hubs made specifically for it and rims drilled for the extreme non drive side bracing angle.
Last edited by bm0p700f on Mon Sep 17, 2018 8:47 pm, edited 1 time in total.

FilmAt11
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by FilmAt11

Thanks for the recommendation - 2x both sides. Noted for the future. I had a Williams System 19 from several years back laced 2x/2x that was really solid.

shimmeD
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by shimmeD

I've laced mine heads-in NDS (better bracing angle being my reason) and am going to ride it (Veloflex 23mm already glued on) against bm0's advice. I'll have to check the tensions, the NDS side were a little less but I didn't note down.
Film, what rims are those? Mine weigh 1044g differences to yours being Pillar 1420 spokes and the 210g 2:1 bhs hub (don't know which model), with Farsport 23x25mm tub rims.
Less is more.

bm0p700f
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by bm0p700f

it will probably be fine I did say there is an increased risk of flange failure not there will be flange failure.

shimmeD
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by shimmeD

:beerchug: Thanks Malc, I appreciate your posts and value your opinions.
Less is more.

FilmAt11
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by FilmAt11

Those are Loltra 20x20.5mm rims (239g, 240g).
Last edited by FilmAt11 on Tue Sep 18, 2018 10:54 pm, edited 1 time in total.

shimmeD
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by shimmeD

Jolly good looking wheels, congratulations :thumbup:
I did think of going heavier gauge on the NDS like CX-Sprint but decided against it having already decided to go 23mm wide rims rather than 20. Should be sweet for a low-powered light-weight in any case.
Less is more.

by Weenie


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