The wheelbuilding thread

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

Hugo-

I think 2x would work well for 20h. But it doesn't make sense to use the same spoke count front and rear. The rear is always weaker than the front due to dish, and it gets more stress. There's more weight on the rear, most riders can lift the front for obstacles but not the rear, and worst of all, it gets the pedaling force in addition to holding up the back of the bike.

I'd do 24h rear. And I'd use Race spokes for the DS. That will make the wheel stiffer laterally and it only costs about 12g.

Speaking of weight, those rims are nice but they're not WW. It doesn't make sense to me to start with kind of heavy rims and then go all WW on the build.

If you don't like radial lacing, try 2x both sides on the rear and 1x on the front. I've done a few that way and I like the way it works. It's also a little easier on the front hub flanges if your hub is known to deform under radial lacing (the BHS hubs don't seen to have that problem).

danny
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by danny

what are the best nipples for carbon rims?

Hugo7
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by Hugo7

eric wrote:Hugo-

I think 2x would work well for 20h. But it doesn't make sense to use the same spoke count front and rear. The rear is always weaker than the front due to dish, and it gets more stress. There's more weight on the rear, most riders can lift the front for obstacles but not the rear, and worst of all, it gets the pedaling force in addition to holding up the back of the bike.

I'd do 24h rear. And I'd use Race spokes for the DS. That will make the wheel stiffer laterally and it only costs about 12g.

Speaking of weight, those rims are nice but they're not WW. It doesn't make sense to me to start with kind of heavy rims and then go all WW on the build.

If you don't like radial lacing, try 2x both sides on the rear and 1x on the front. I've done a few that way and I like the way it works. It's also a little easier on the front hub flanges if your hub is known to deform under radial lacing (the BHS hubs don't seen to have that problem).


Cheers.

Just to be clear I'm only still tooing and froing on the front lacing. The rear will be 28h (2x NDS and 1x DS (heads in)). It's good to hear that you think 2x will be ok on the front though. Would 1x be better, or are we really talking about no gain here? Usually I don't put aesthetics first but that really is my only reason for not going radial.

If I go x1, are there any good links to how to do it? In the past I've only done 3x, 4x, and crowsfeet. This will be my first low spoke count road wheelbuild. I am unsure whether to alternate the heads in/out or have all out like here:

http://farm3.static.flickr.com/2626/3729816308_bb5df5cbe5_b.jpg


I take your point on the weight of the rims, but I'm set on wide clincher rims and have a limited budget - which limits the options. I could go for the A23's, H+Son's or Pacenti SL23... but they're Not a huge amount lighter and all shallower. Although the Pacenti isn't much shallower, it is more expensive. So overall I've gone for more width and depth with an eye on price. The BHS hubs seem to be well reported and aren't expensive so there doesn't really seem a reason not to use them. I'd usually never worry about things like hub weight due to it's location relative to the wheel.

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Zen Cyclery
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by Zen Cyclery

@danny- It depends on which carbon rims you are talking about. All the carbon hoops that we build on require internal hex nipples. It is totally brand dependent though.

eric
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by eric

Hugo- it wasn't clear from your earlier post that you were talking front only, but now it makes more sense.

I don't notice any difference in ride between 1x and 2x on the front. When I do 1x I do what's in that picture- heads in. I copied it from a wheel that Troy Watson built for me. I think that pic is one of his. That brick wall looks familiar.

It's very slightly easier to lace than 2x. I do it to copy the rear layout- if the pulling spoke on the rear crosses to the inside I make the front spoke of each crossing pair on the front wheel cross under the rear spoke. No one but me will notice it and it makes no difference in strength.

Thinking about it some more I'm not sure that 2x lacing will work. It's theoretically tangential making for the most flange backing the spoke, but it might also have the spoke heads under spokes. The hub is strong enough for radial lacing so you don't need to go 2x with it. I'd do 1x.

On the BHS hubs the spoke hole is chamfered more on the outside than on the inside. So if you lace heads out the heads sit flush to the flange. That looks cool but it leaves the elbow unsupported on the other side. Eventually they start breaking, and with 20h you will be doing a field retruing so you can ride home. So I have taken to lacing the fronts all heads in on those hubs. With the wide hub the spokes are pretty close to the fork down near the hub. If you have a fat fork there might be clearance problems but I think it'll fit the vast majority of forks (it fits my enve 1.0 which is fairly fat).

The BHS wide rims are nice rims- the pair I got were straight, and they're really stiff. They're just not WW.

danny
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by danny

Zen Cyclery wrote:@danny- It depends on which carbon rims you are talking about. All the carbon hoops that we build on require internal hex nipples. It is totally brand dependent though.


I have bought two chinese carbon tubular rims (external nipple9 and I will use dt swiss 240 hubs plus sapim cx-ray spokes but I don't sure if better to use exagonal nipples or if better to use a shim under nipple head.

bm0p700f
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by bm0p700f

If the flanges are small 2x might work. Personaly all 20 spoke wheels are radial for me and pick a hub that can cope with that.

To lace 1x is simple. With 2x lacing you palce your first heads out spoke in the hub and into the a hole just left of the valve hole. 5 spoke hole in the hub on (clockwise) you put a heads in spoke and that goes two spoke holes in the rim to the right of the valve hole. For 1x lacing the number of spoke hole in the hub between your first heads out and second head in spoke is 2 not 4. That way you will have perfect 1x lacing.

Pretty easy really.

bm0p700f
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by bm0p700f

Danny it will depend how deep the spoke bed on your rim are. On some the spoke bed is deep enough to make internal nipples more useful. Not enough info to answer your question.

Hugo7
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by Hugo7

Cheers.

Looks like 1x it is.

Now just to work out the spoke lengths and order :)

DividedVolta
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by DividedVolta

Quick follow up on some posts I made a while back.

I'm considering using Kinlin XR-270's instead of 200's. My previous build was set on 24/28 with Sapim race front/cx-ray rear. I have been thinking and decided I wanted something a bit deeper (thus the 270's) and was wondering if I could lower the spoke count a bit. I'm almost always within a few pounds of 155lb; would it be advisable to run 20/24 or should I stick with the 24/28?

Thanks.

bm0p700f
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by bm0p700f

20/24 are race or event wheels in my opinion, not something to be used day in day out but of course you can do that sucessfully. You will probably be fine on a 20F/24R build given your weight and so long as you do not have a history of snaping spokes.

Personally for training wheels more spokes the better and 24F/28R wheels using a kinlin XR-270 rim would meet that intended use well for you. I can't remember what your intended use is. If your roads are crap then more spokes is better.

DividedVolta
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by DividedVolta

That answered my question. Thanks!

KLabs
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by KLabs

bm0p700f wrote: ... Personally for training wheels more spokes the better and 24F/28R wheels using a kinlin XR-270 rim would meet that intended use well for you. I can't remember what your intended use is. If your roads are crap then more spokes is better.

Hi bm0p700f, when you refer to crap roads and more spokes, is that for torsional stiffness and strength, or/and lateral and radial stiffness/strength ... thanks

bm0p700f
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by bm0p700f

Radial stiffness for aluminium alloy rims and steel spokes is not dependent on spoke count. Edit actually it does a bit. That is why for low spoke count wheels (20F/24R or less) very stiff rims are needed so that radial deformation does not lead to a significant spoke tension drop. The extension of a NDS Spaim Laser spoke with 1.5mm diameter is on the order of 0.4-0.5mm. Given radial wheelstiffness is generally not much more than 4000N/mm except perhaps for the stiffest deep rims. 2000N of radial loading is possible on various lumps and bumps and would [nearly] unload the NDS spokes.

Edit * thicker spokes does increase radial wheel stiffness maybe by enough to account for increase in spoke life that you would expect. The reason being the value for rim stiffness are higher than I thought. More spokes if there enough so more than one is being unloaded (in low spoke count wheels though this may not be the case) should also have the same effect as two spokes in parallel are like two springs twice the stiffness.

Radial wheel stiffnes = radial rim stiffness/(1+ (rim stiffness/spoke stiffness)) I hope you can see from this if spoke stiffness rises the bottom term in brackets (rim stiffness/spoke stiffness) reduce in size so the bottom term tends to 1.

Lateral stiffnes goes up of course with more spokes and there must be alot of side loading on a wheel on uneven and holed surfaces like the roads of Suffolk and Essex. It's that lateral loading combined with the radial loading that does spokes in.

To make a 20F/24R spoked wheel work for everyday use I think you need a rim that is even stiffer (and therefore heavier) than the XR-270. The more radial stiffness a rim has the more lateral stiffnes it has as well, the two work together to make low spoke count wheels work.

The Kinlin XR380 fits into the catagory of a stiffer rim so does the DT RR585. I have built up a set of XR-380's yesterday that weighed 1646g. The customer want these not as everday wheels though.

Currently I am up with baby daughter she does not want to sleep, she is finally going off.

Now it edited I hope that answers the question. really what is needed are some strain gauges on wheels of different spoke count and rim types and gather some hard numbers. I would love to do that.
Last edited by bm0p700f on Tue Feb 05, 2013 12:29 pm, edited 4 times in total.

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kavitator
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by kavitator

XR-380 is really stiff - a wheelset on 16(front radial)/18(rear 2:1) cx rays is used sucsesfully for training some 1000km for now

bm0p700f did you try spuerspokes for NDS? or Lasers are enough elastic

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