Re: [CR] Spanish Lace / Crowsfoot spoking patterns.

(Example: Framebuilders:Chris Pauley)

From: "Andrew R Stewart" <onetenth@earthlink.net>
To: <Jon@FAI.US>, <billydavid13@comcast.net>, <classicrendezvous@bikelist.org>
References: <1725943193.1152201261448392041.JavaMail.root@sz0035a.emeryville.ca.mail.comcast.net> <A3E21BB19CA64AB69A425F95CAF7C9AB@QWERTY28>
In-Reply-To:
Date: Tue, 22 Dec 2009 11:12:41 -0500
Subject: Re: [CR] Spanish Lace / Crowsfoot spoking patterns.


Jon- One of the big problems with this type of discussion is that no real tests have been done to measure the claims. Sure a builder will say this or that, given his experience or ego. Math will suggest which spoke pattern has what angle, force, tension compared to another pattern BUT I believe that the range of actual build up tensions and techniques (for any one pattern) will have a larger effect on the measured results then calculated assumptions.

We do have one test that does give the answers indirectly. That's the real world and it's history of spoked wheels. It's not "scientific" but it is the best source of guidance that I know of. Why is it that most factory wheels use only one of a very few patterns? Because it is what works best for the reasons that most manufactures care about. Consumer acceptance, cost of manufacturing, and reliability being the biggies. Note that I mentioned consumer acceptance first. This is a combination of show room voting (buying the wheel/bike) as well as riding feedback (the "feel", wheel stability and lifespan). Once the voter doesn't place value on the spoke pattern (think Wal-Mart) cost of manufacturing VS reliability rules. One might hope that reliability would be the highest priority but it, perhaps, is the last (more often in the more expensive end of the market!) When the cost differences between one pattern and another are a small portion of the wheel's cost (think hand made "custom" wheels) then either consumer view or reliability is at play. And guess which usually wins out.

I see far more wheel work with high end wheels then basic grade ones proportional to the numbers sold. Yes, in total numbers the department store (and basic grade LBS products) provide me with more work orders. But for the number of high end wheels sold they have more problems. (And the problems are more difficult to service, cost more to service, often suffer a greater down time). One of my grips is that at the high end the expectations are fueled by the ride at the moment and not the next ride. I've long since lost count of the riders that bitch and moan when their pricy rear wheel breaks a spoke and the wheel is in the shop. Yet they continue to buy wheels with fewer spokes doing more work, often using propriety designs that change annually. It's like the dog chasing it's tail sometimes.

Again there's a reason why the vast majority of wheels use 3x patterns.

Now back to the OP's reason to deal with all this spoke mumbo jumbo. He was having clicking issues. That's two parts rubbing/moving against each other. Outside of radial or non interlaced patterns, spoke contact noise is either worn contact points (a slight notch in both spokes at the crossing) or too little tensioning for the forces at hand. Seems to me that rebuilding the wheel with new spokes, at a higher tension, in any pattern (including the original one) would cure the noise, at least for a while.


----- Original Message -----
From: "Jon M. Crate"
To: billydavid13@comcast.net
Sent: Tuesday, December 22, 2009 12:12 AM
Subject: Re: [CR] Spanish Lace / Crowsfoot spoking patterns.


Billy & all, After reading the arguments made by Robert Torre on rear wheel strength, I was buying into it:

http://spokeanwheel.110mb.com/lacingsr.htm

Do any of you mechanical engineer types have specific knowledge about these claims or anyone aware of actual testing done?

Thanks, Jon M. Crate Marietta, Georgia

-----Original Message----- From: classicrendezvous-bounces@bikelist.org [mailto:classicrendezvous-bounces@bikelist.org] On Behalf Of billydavid13@comcast.net Sent: Monday, December 21, 2009 9:20 PM To: classicrendezvous@bikelist.org Subject: [CR] Spanish Lace / Crowsfoot spoking patterns.

Hi all. I don't build a lot of wheels, and i'm rather slow. These days i typically use 3X rear w/ DT Competition 14/15s and 2X front w/ DT Revolution 14/17s w/ alloy nipples. Front wheels let you get away w/ a lot even radial but i don't trust radial [i've seen hub flanges pulled apart w/ radial spoking and that's a disincentive] and i HATE the way it looks. But, hey, do what you want. When it comes to rear wheels i'm not going to play around. The various novelty patterns have a certain appeal but it's limited. I'm not going to argue that these unconventional patterns are doomed to certain failure but nothing is as strong or as classically beautiful as standard cross laced wheel. I'm all for doing the unconventional when it makes sense, but not just for the sake of being different. As for the unconventional patterns adressing any problem other than the builder's boredom? Well P.T. Barnum said there's one born every minute. Happy holidays! Billy Ketchum; Chicago, IL; USA. _______________________________________________

_______________________________________________

Andrew R Stewart
Rochester, NY