79pmooney

Spoke windup - a good wheelbuilder finishes his build without windup. With enough lubrication and a good sense of touch, finishing with none or little enough to never matter isn't hard. (If you lube the rim seats for the nipples with grease, it is easy to feel windup. It is a lot harder to tighten the nipple than loosing it.)

Ben

Ben I.

The friend that will be doing the wheelbuild said it would look weird if I had different cross patterns on the front and rear and I can see how it would. He also suggested 2X but I can't remember if he thought it would be enough, that 3X wouldn't be doable for one reason or another, or if it'd be overkill to do more than 2X.

How do you know for sure that you can do a 3X?

FBinNY 

This says it all. If the friend is someone you consider qualified to do the build, he's the one most qualified to advise on the spokes.

Anyone other than you as the user and him as the builder is just a kibbitzer.

I certainly can't advise, because I don't have nearly enough info, most importantly, what the builder has in mind about your needs. In fact, I can envision a situation where you might use all three spokes on a pair of wheels, with the front having the lightest, and the rear splitting gauges right and left.

79pmooney

"Flex" has two components. Resistance to stretch and resistance to bending. All that matters here is resistance to stretch. Every aero spoke has an equivalent DB spoke of the same weight. That DB spoke will have the same cross-section area and hence the same resistance to stretch and build an identical wheel. The bending is a totally different matter. Aero spoke are very stiff along the long axis of the cross-section and very bendy across. But that matters zero until something hits your spokes. As far as the different forces you are going to apply - braking, accelerating, bumps, steering - they all simply load the spokes in tension. Spokes act like simple wires. Cross-sectional area and material are all that matter. (Plus stresses and stress concentrators created by the manufacturer's process and what the build imposes. A quality spoke should not have issues out of the box. (There is go reason the aero spokes are so much more expensive. A shoddy manufacturing process would (near guaranteed) create aero spokes that would quickly develop a reputation similar tot the early stainless steel spokes in the '70s, shiny, sexy and unreliable.)

Ben

Ben I.

Yeah, regardless of which spokes I end up with I plan on having at least a couple extras on hand in each length. Where I'm most likely going to get them from has Aerolites and Aero Comps in boxes of 20 and then Revolution, Competition, etc in boxes of 72. If I go with the latter ones, I'd probably get them another place since having 60 extra in some lengths is overkill

By the way, the thicker one you're thinking of is the DT Swiss Aero Comp. It's supposed to be a bladed version of their double butted Competition spoke.

I know a huge amount of it comes down to who is building the wheel and I know my friend knows what he's doing but I also want to be able to true them and work on them myself without too much fuss. If it'll be harder for me to work with double butted because I'll have to worry a lot about windup I'd probably go with bladed then.

Bike Gremlin

Many folks don't tension bladed spokes properly. When they do, dealing with the twist is harder to deal with, even when holding the bladed part.

FBinNY 

This is a serious question.

Do you TRUST your wheel builder friend?

If so, then act like it.
If not, as seems to be indicated by your questions here, then I suggest you find someone else, because you'll be second guessing his work until the cows come home and will never have confidence in the finished wheels.

BTW- if you had come to me with all these questions, and suggestions from a forum, I'd return your parts and suggest you find someone else to build the wheels.

Bike Gremlin

Divide spoke count by nine, and round down to the largest whole number. That is the max number of crossing you can do with most hubs. The more crossed the spokes are, the stronger the wheel resists twisting pedalling force, with less "torture" to the spoke elbows.

On some hubs, flanges are made so that spokes interfere with elbows of adjacent spokes when doing the max X pattern - then you go with the 2nd "best".

Spoke unwind is easy to fix. Some grease on place where nipples touch the rim and on spoke threads, then, when doing final tightening, overdo by 1/4 turn, then unscrew back by the same amount. If the screwing back is too easy - the spoke was twisted. You can also feel if the spoke twisting by holding it gently with the other hand when tightening nipple.

P.S. I love my wheels over-engineered, with as little worry about them as possible - so I never go with fancy stuff. 36 round spokes per wheel, double walled aluminium rim and brass nipples. IMO, makes little gains doing otherwise, unless racing (against a clock or other competitors).

79pmooney

I just drew up a 28 hole 3X wheel in a CAD program. Looks quite doable. The spokes come nowhere close to the next spoke head. (And even if they touch, it isn't a big issue. A 4X 36 hole large hub has significant contact but I regularly get three rims to a set of spokes on my Campy Tipo winter wheels and I documented a set with low flange hubs going 17,000 miles.)

As far as looking different? We cyclists are locked into a "its gotta look this way" culture. Motor cycles, performance cars, trucks and airplanes have been using different wheels front and real a long time. My fix gears use Velocity Aero rear rims and significantly lighter Open Pros in front. The Velocities for their deep usable braking surface top simplify sliding the wheel back and forth as I change cogs.

Ben

Ben I.

I definitely see where you're coming from. To be fair, I haven't had a chance to talk with my friend in a couple weeks and when we did talk it was somewhat quick because he had somewhere to be. I think I'll call and have an actual talk with him about all this, thanks for setting me straight.

The other part is that he is very experienced where I am not so he bases his suggestion on that experience, i.e. he knows all about working on double butted spokes where I am a little intimidated by them because I know you have to be careful about windup, etc. Probably a good chance to learn more.


I'm going with 28 front and 32 rear so they both theoretically will work but might be pretty close, especially in the front so I probably will play it safe and do 2X but as mentioned just above, I think I'll call my friend and talk more in depth with him about all this.

rpenmanparker 

Best crossing pattern depends as much on flange diameter as spoke count. You can't just divide spoke number by 9 and always get the correct best number. The best pattern has the spokes tangent to the flange or, more correctly, parallel to a tangent to the flange. You don't want high crossing number as much as you want that tangent. The larger the flange diameter, the lower the best number of crossings for the same number of spokes. Obeying that rule gives you the true best crossing number with no fouling of one spoke on the head of another. The tangent spoke line provides the most effective pulling of the rim by the hub without the spokes rotating in their homes, i.e. without the hub winding up.

As for spoke windup being easy to fix, it is not nearly as easy as not having the problem to begin with. If you built with lightweight spokes, you would know how problematic windup can be. Besides you say you like your wheels over-engineered, yet you opt for round spokes. Swaged, bladed spokes are demonstrably stronger than the equal weight round spoke. The flattening process imparts significant additional strength to the spoke. If you really wanted an over-engineered wheel, you would pick bladed spokes of whichever weight class you think necessary.

FBinNY 

**********

I agree that the maximum as determined by formula isn't always the best, but what you say later doesn't make sense. The X/9 (-1?) is the maximum number and the closest to tangent by virtue of that, REGARDLESS of flange size.

There are a number or reasons for going with fewer than the max, and flange size is one factor. Too small and you may have spoke/spoke head issues at the 1st cross. Too large, and you have the spokes too far from the radial at the rim.

My general rule (with exceptions) is that the "parallel" spokes must be closer at the hub than at the rim, so it boils down to the flange width relative to the distance between the 2 spoke holes in the rim (skip the one going to the other flange).

As for spoke twist, there are multiple ways to manage it. None really better or worse as long as it gets the job done.

rpenmanparker 

I was more disputing the notion that as many crosses as possible is desired in a theoretical sense. My point was that the object is not to get a large number of crosses as much as a tangent spoke line. If the formula does that for you, all the better, but suggesting that X/9-1 is a compromise that you have to settle for when you would rather X/9 is what I don't think is right...if X/9-1 gives the tangent.

Ben I.

Thank you for all of the responses, much appreciate the opinions and suggestions, however as @FBinNY mentioned, I need to trust my wheelbuilder which was mainly a problem with me only being able to have a quick chat with him regarding spokes so I knew what he recommended but at the time, didn't think to ask the why and didn't know other questions to ask. Now that I know WHY he recommend what he did, I understand it and will wholeheartly go with his recommendations.

So this is what I will go with...

As mentioned already decided on Hope Pro 4 hubs and HED Belgium Plus disc rims, 28 front and 32 rear with either Wheelsmith or DT Swiss double butted spokes in a 2X pattern with brass nipples to finish it off.

rpenmanparker 

I think you will find that 3X is more desirable in the back with 32 spokes.

FBinNY 

This is exactly what makes no sense to me. Tangent to what? If you mean as close to tangent to the hub, that's almost by definition, the maximum number of crosses. I can't imagine when it wouldn't be.

If OTOH, you don't mean tangent, and are referring to the "parallel" pair being closer to parallel, as I described in my post above, then you're simply choosing the wrong word.

FWIW - whether by formula or chart, the maximum number of crosses by drill are"

20 or 24 = 2x (true tangent on 20))
28 or 32 = 3x " on 28
36 or 40 = 4x " on 36
44 or 48 = 5x " on 44 which, AFAIK, doesn't actually exist.

rpenmanparker 

True tangent to the hub.

Are you sure about those true tangent designations. I don't know the right way to determine that, but it seems to me that the rim hole the spoke needs to head for is 90° from the rim hole on the radius from the hub hole. The number of holes between the radial hole and the destination hole for a certain number of crosses is 4(a-1)+2 where a = the number of crosses. For a 40 spoke wheel with 4 crosses the 10th hole is the tangent hole and the destination hole of the spoke. For a 36 hole wheel with 4 crosses the 9th hole is the tangent hole but the destination hole is the 10th hole. Sorry if my lingo is confusing. Of course there is some error in the tangent due to the flange radius, but it seems that is negligible.

FBinNY 

OK, so then flange sizes isn't relevant, except in very extreme cases of large flanges on small wheels. Even there the line of the spoke at the hub won't be the issue, it's a problem at the rim, which is one reason why we don't always go with the max cross.

Consider.

True tangent mans that the "parallel" spokes come to the hub opposite each other at the diameter.

So, they come to the halfway point in the circle of spoke holes, or at 1/2 the number of holes in the flange.
That means (if you do the math for the various possibilities), equal to or less than 1/9 the total number of holes.

Feel free to find exceptions, but you'll be extremely (very extremely) hard pressed to do so. Honestly, I wish I knew what your objection is (was).

rpenmanparker 

No objection. Just using this discussion as a learning exercise. I had never heard of the 1/9th rule. I just knew that spokes in a crossed pattern were supposed to be tangent to the hub. Knowing how to find the answer to what that is is important, but I just like focusing on why it works.

FBinNY 

There's no rule, it's just his method for knowing. I use 4x/36, then add/subtract one cross for every 8 or less fewer spokes.

Either way, I suspect that you're missing the point (maybe not) about spokes being tangent. The flange doesn't matter. The key is that you want spokes to be offset from radial so there's a moment arm (right angle distance) from the spoke's line of action to the hub's center. The actual position of the spoke isn't the key, the length of that moment arm is.

If you think a moment (no pun) you'll see that you get the biggest moment arm will be when the spoke is tangent to the hub, or as close as the pattern allows. But modern spokes are strong, and the large flange hubs of the past are no longer considered necessary. So, if you accept that the less than 1" moment of a SF 32h/3x pattern is fine (and time has proven it is), than there's plenty of forgiveness for fewer crosses on a larger flange.

In fact, 2x/32 on SF hubs has proven itself for most applications, as has tangent on only one flange, so there's even more forgiveness than ideologues are willing to consider.

So, add cross to all the other minor, niggling things that we can debate on forums as if they really matter, even though they don't.

Doge

I agree it is personal preference on which a person chooses but there are some facts.

Like you can't see a wound twisted round spoke like you can non-round one. And as I mentioned - there are ways to keep the round from winding around - it is just more difficult and many builders don't do it.

A DB spoke (aero or round) is less stiff than a straight one of same material. It may not be stronger, it will always be stiffer.

Then there is/are the properties of materials and how the spoke is made/bent etc..

FBinNY 

I know I'll get grief for being a Grinch this time of year, but am I the only one who sees lots of words and no facts?

rpenmanparker 

Understood.

rpenmanparker 

Huh?

rpenmanparker 

When you talk about spoke stiffness, the only kind that matters is tensile stiffness, how easy/hard it is to stretch the spoke lengthwise. Two spokes that weigh the same likely have the same average cross-sectional area and therefore the same tensile stiffness. A bladed spoke flattened from a round spoke will not change in tensile stiffness. Yes, the bending stiffness would be less, but that doesn't matter.