Sapim CX-Ray or DT Aerolites?

[petitelilpettit]

Hello everyone. I'm debating on building a carbon wheelset similiar to the ones on Spinelli's blog: Edge 1.38 rims, White Industries hubs. However, I'm wondering which spoke would be the better of the two.

Wheelbuilders, what do you think? The pros and cons of either one? I know a lot of people like the Sapims, but I'm tempted to use DT's just for the namesake. Opinions?

Pettit

[frenk]

They are almost identical. My wheel is built with cx ray, when I broke a couple of spokes I used aerolites because I hadn't any cx ray anymore, and you can't tell the difference without looking very close.

The only thing I noticed is that (with my hub) I had to bend the cx rays at the elbow to go straight to the rim, while aerolites already pointed to the right direction.

[Ligero]

They are nearly identical. The Dt blade is a hair wider (2.3 vs 2.2mm) and the transition from blade to round is longer on the Dt.

Another thing I have noticed with all Sapim spokes vs Dt is the Sapim spokes take more before they will stay permanently bent. If you take a Dt spoke hold each end and bend it 90 degrees it will stay bent if you do the same thing with the Sapim spoke it will snap back to straight or nearly straight. I don't know if that helps the wheel in any way but it is just something I noticed.

[FMS_rider]

I recently had a pair of wheels built with DT Swiss Aerolites rather than Sapim CX-Rays based on the advice of a local wheel guru whose judgement I trust. He has seen a number of failures of CX-Rays on factory-built Cane Creek wheels on which he confirmed that the tension was at the manufacturer’s spec. He attributes the failure to metal fatigue from flexing --perhaps accelerated as a result of the slight bend at the hub described by frenk? (my speculation)

Perhaps one of the metallurgical gurus who post here could comment on whether a softer alloy (Aerolites) or a stiffer alloy (CX-ray) would be more resistant to fatigue from the slight flexing that occurs when wheels are ridden. I suspect that this is not a simple issue because a stiffer spoke is going to flex with a different pattern over its length than a softer one, so that the distance over which the flexing occurs would differ. Obviously the shape at the J-bend is also going to be a factor and it is clearly different in the 2 designs.

I have only ~500 miles on my wheels with the Aerolites (DT Swiss 240 hubs and R1.1 rims), so all I can say is that they look great and have remained absolutely true for that short distance (without any significant pothole hits). I also had them built very conservatively with all brass nips and 32 3-cross in the rear and 28 radial front.

Lew

[marle]

They are nearly identical. The Dt blade is a hair wider (2.3 vs 2.2mm) and the transition from blade to round is longer on the Dt.

Another thing I have noticed with all Sapim spokes vs Dt is the Sapim spokes take more before they will stay permanently bent. If you take a Dt spoke hold each end and bend it 90 degrees it will stay bent if you do the same thing with the Sapim spoke it will snap back to straight or nearly straight. I don't know if that helps the wheel in any way but it is just something I noticed.


From the Nova's 'Secret's of the Samurai Sword'

Q: So the number of defects actually determines how strong it is?

Vinci: Yes. If I take a piece of copper tube, for instance, it's relatively easy to bend it the first time. And if I were to install it in a home or business, I could straighten it out as needed. But if I make a mistake and try to change the shape of it again, it gets much more difficult to straighten it out the second time and even more difficult the third time. Because every time I bend it, I create lots of microscopic defects inside, and the more defects I have, the stronger the material gets.

So the DT is made of harder steel is my guess

[brians647]

From the Nova's 'Secret's of the Samurai Sword'

Q: So the number of defects actually determines how strong it is?

Vinci: Yes. If I take a piece of copper tube, for instance, it's relatively easy to bend it the first time. And if I were to install it in a home or business, I could straighten it out as needed. But if I make a mistake and try to change the shape of it again, it gets much more difficult to straighten it out the second time and even more difficult the third time. Because every time I bend it, I create lots of microscopic defects inside, and the more defects I have, the stronger the material gets.

So the DT is made of harder steel is my guess

Via having more defects?

[marle]

The defect is in the atomic structure means some atoms are not in a symetric / lattice pattern.

[brians647]

The defect is in the atomic structure means some atoms are not in a symetric / lattice pattern.

Gotcha (I think... :rolleyes: )