Originally Posted by
Kontact
You have been learning from trial and error, and through that process came to some mistaken conclusions.
I learned how to build wheels through
Hjertberg’s series of articles in Bicycling Magazine. Yes, I learned through trial and error but that is the way that most people learn and there is nothing wrong with it. As a scientist, I had to develop new ways of doing something by exactly that method. Much of my knowledge and conclusion come from observation and testing…something that has been honed by 40 years of doing scientific research.
I was taught how to build wheels by a graduate of the Wheelsmith wheelbuilding course. I have built, warrantied, trued and repaired many more wheels than you have - and the vast majority were straight gauge 14g spokes. An incredible number of those wheels had only 20 spokes per wheel.
Good for you but you also had to go out and build wheels which included not a little bit of error. Making mistakes is one of the best ways to learn how to do something.
The advocacy for heavier elbowed spokes was for machine built wheels because the elbows were not going to be hand seated, and the heavier elbows protected the spokes a little bit better. But if you are seating the elbows, that isn't necessary because the bend is not being constantly stressed. I have a wheelset that I have been riding for a decade that is 28h and 15g unbutted spokes. 14g are more than up for the challenge of building a wheel if the rim is sufficiently stiff. Not if you are using 280 gram box section rims, though.
And your evidence for this idea is what? It would be lovely if machine built wheels would use spokes with 2.3mm heads but no one…
no one!…does that. Every machine built wheel out there use straight 14g spoke. Triple butted spokes cost more than double butted spokes and double butted spokes cost more than straight ones. As others have pointed out, spokes for most machine built and OEM wheels use whatever cheap spokes they can get their hands on. And lots of those spokes may not be made to the exacting metallurgical standards used by name manufacturers.
As to “rim stiffness”, a slight increase in the amount of aluminum used does not significantly increase the stiffness of a rim. Addressing only aluminum here, it is a soft metal with very little stiffness. There are engineering tricks to make it stiffer but the cross section of rim doesn’t lend itself well to those tricks. A 535g Velocity Dyad isn’t going to be significantly stiffer nor stronger than a 450g Velocity A23 with a similar profile.
What do you think 'good' spokes are made of? The stainless steel used is an alloy which is not strong - its main qualities are resisting rust and forming nicely. It has no hardening alloys. I haven't seen an unplated spoke rust in 30 years. Spokes are not made of a magic alloy, they are made of a somewhat soft and malleable one. The OP has already told us what the problem is - low and uneven tension. Why conclude that an obvious tension problem is a metallurgical problem.
Perhaps you should learn a thing or two about stainless steel. The “stainless” part comes from the addition of chromium to the iron which
is the hardening alloy. Nor is stainless steel “weak”. It is stronger than mild steel. That said, OEM wheels aren’t usually spec’d with the higher quality spokes from DT, Sapim, Wheelsmith, Pillar, etc. Perhaps SamSam77’s problem started with low tension but it is also something of a metallurgical problem now. Broken spokes, especially on a low spoke count wheel, adds undue stress on the remaining spokes which can then become failures themselves.
I don't know where so many people have accumulated the knowledge that makes them want to replace all the spokes every time there is a tension issue, but it seems to be from reading posts on forums - not working as a mechanic. When properly built, the spokes will be the last thing to fail on a rim brake wheel.
No one is advocating replacing spokes because of a tension issue. We are advocating replacing spokes because of a
breakage issue. And the idea to replace spokes rather than chase endless breakages comes from lots of peoples’ experiences with trying to fix a nearly endless cascade of spoke failures. Tension also isn’t the
only answer to every spoke problem. To say so suggests that you don’t understand wheel dynamics.
Replacing all the spokes and the (already brass) nipples will cost $30+ per wheel plus $40 labor per wheel. At that point you could buy some new wheels for just a few dollars more.
More like $50 to $80 depending on the spokes and more like $80 to $120 in labor. Didn’t you imply that you built wheels commercially? You must build them cheap. That said, it still comes down to the same problem as SamSam77 has with the OEM wheels. He is going to just trade one problem wheel for an other possible problem wheel. Alternatively, replacing the spokes with better spokes ***cough!****triple butted***cough!***would result in a more durable wheel with fewer problems with the existing equipment. At the very least he should consider replacing the existing wheel with a 32 or, preferably, a 36 spoke wheel if going that route.
And I am all for learning to work on bikes, but you don't do that by starting with screwed up stuff. That leads you down the path of erroneous conclusions, like Cycomute's. Either learn from someone who knows what they are doing, or start with mostly new components of the correct dimensions and keep control of all the steps. The OP has a problem that needs solving right now, and a pro adjusting his existing spokes is the simplest and least expensive path forward. Why do you guys always want everything to be harder than it needs to be?
My “path” isn’t erroneous. Yes, SamSam77 should probably try to find someone to help. I think I suggested that earlier. But if I haven’t, I agree with finding someone provide guidance. That said, it is possible to build a wheel from a book, a series of articles, or individual instruction. All three as valid ways to learn how to build wheels but the most important part of learning how to build wheels is to
build the damned wheel!