First indication that galvanic corrosion is a potential problem

[mrex]

First indication that galvanic corrosion is a potential problem

This is the same reason why i already asked in other threads, will apple even allow to mix steel band with the sport model. Electrochemistry will take place and you cannot avoid it. But the question is "how badly and quickly?" Aluminium itself has this unique feature, the protection system forming aluminium oxide -layer on itself, but if aluminium is mixed with a steel, we need to consider electrochemistry and hence alumium which is less noble metal than steel starts to corrode while steel being as cathode in a galvanic corrosion process remains. These two metals dont need to touch each other, just a water drop is enough and forming a bridge between these two metals. Water (rain/sea/lake/...) contains ions and the salt bridge is formed. With the latest studies they have noticed that chlorides accelerate this process (basicly our sweat).

And while the aluminium oxide - layer is protecting aluminium for the further oxidation, it gets easily scratched and exposes aluminium for the oxidation. However, aluminium tends to react with oxygen quite fast and the new protection layer is formed. But around your wrist, both metals are mechanically scratched often and getting moisture and especially chlorides.

So im still wondering will apple even let you mix these two together or do you loose the warranty.

I should say that in a normal use, you probably cant see any corrosion at all, but thinking about "sport" (being wet often) that might be a differend thing. In a normal condition aluminium oxide will protect the aluminium but if constantly being wet it wont protect and alumium oxidizes...

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I mean this so kindly, but I'm beginning to wonder if the forum members on MacRumors are a bit nuts.

if you are a chemist like i am, you cannot be thinking about it. Even Apple cant avoid basic chemistry...

 

[caligurl]

ya..... they mean that the shiny silver or black stainless band connectors aren't going to look so hot in the matte sport watch....

 

[JayLenochiniMac]

ya..... they mean that the shiny silver or black stainless band connectors aren't going to look so hot in the matte sport watch....

Again, that falls under "may not match the finish (of that specific collection)." They clearly mean something else in adding "or may not be optimal for use with that specific collection."

 

[01silver4]

Not if it is Anodizing Aluminium as in the Apple Watch case (similar with unibody iPhone, Macbook, iMac).

This is interesting read: http://www.engineerguy.com/elements/videos/video-anodizing.htm

Anodizing aluminium starts out much like titanium. Using aluminum as the positive electrode, engineers first pass enough current to grow a thin "barrier" layer - similar to that which forms naturally. Then, as the anodizing proceeds, the current "pushes" this barrier deep down into the aluminum converting the aluminum above into a very porous oxide layer. It isn't a layer being put on top, but instead the reaction consumes and converts the aluminum; this is one of the reasons it's so effective at preventing corrosion. The pores in this layer give the aluminum a unique characteristic important for a consumer device: The ability to be colored. The pores formed on the surface have a honeycomb pattern. Inside these layers one can place dye of any color. Once the pores are filled engineers seal the layer by boiling the aluminum in hot water. This closes the pores, locking the color in forever, you cannot scrape it off without removing the aluminum. The toughness comes from the oxide being structurally similar to tough gemstones. Sapphire is an aluminum oxide - with trace amounts of iron and titanium to give it a blue color; it's also the basis of ruby, the same crystal structure with chromium that absorbs yellow-green. Both materials are very hard: Nine on the Mohs scale.

You sir should explain this to all the people on here who worried about the sport model, being scratch to death as soon as it come out of the package etc etc. I have been riding my 2014 CAAD 10 black anodized aluminum with carbon fork, I have put over 5000mi on it so far. And it's still looks new as the day I bought it, not a scratch or ding anywhere. I think it's ridiculous some of the the comments about the Aluminum not being durable enough for every day use. Here's is a photo of my bike, weighs 15lbs and is tough as nails. I will be buying the SG sport model on the 10th.

 

[Ries]

You sir should explain this to all the people on here who worried about the sport model, being scratch to death as soon as it come out of the package etc etc. I have been riding my 2014 CAAD 10 black anodized aluminum with carbon fork, I have put over 5000mi on it so far. And it's still looks new as the day I bought it, not a scratch or ding anywhere. I think it's ridiculous some of the the comments about the Aluminum not being durable enough for every day use. Here's is a photo of my bike, weighs 15lbs and is tough as nails. I will be buying the SG sport model on the 10th.

How about the close up and not against the sun... As someone who uses his bike year round, also in snow, it will corrode and gets dings.

 

[01silver4]

How about the close up and not against the sun... As someone who uses his bike year round, also in snow, it will corrode and gets dings.

No snow here in sunny Florida, but we do have a lot of rain every other day or so. It would rain hard for a little and stop and then the sun would come out again. But I think sweat and sand is worse than snow. I sweat a lot when I ride and it gets on my bike. Here is a few close ups.

 

[01silver4]

No snow here in sunny Florida, but we do have a lot of rain every other day or so. It would rain hard for a little and stop and then the sun would come out again. But I think sweat and sand is worse than snow. I sweat a lot when I ride and it gets on my bike. Here is a few close ups.

And also this is a $5000 bike, so would expect the finish not to easily scratch and ding up.

 

[Mr. Buzzcut]

You sir should explain this to all the people on here who worried about the sport model, being scratch to death as soon as it come out of the package etc etc. I have been riding my 2014 CAAD 10 black anodized aluminum with carbon fork, I have put over 5000mi on it so far. And it's still looks new as the day I bought it, not a scratch or ding anywhere. I think it's ridiculous some of the the comments about the Aluminum not being durable enough for every day use. Here's is a photo of my bike, weighs 15lbs and is tough as nails. I will be buying the SG sport model on the 10th.

Where is there direct contact between the two materials?

Trek had a pretty significant issue with corrosion a while back due to the way they were mounting metal cable stays to their carbon frames. Look it up and you will find lots of pics.

 

[01silver4]

Where is there direct contact between the two materials?

Trek had a pretty significant issue with corrosion a while back due to the way they were mounting metal cable stays to their carbon frames. Look it up and you will find lots of pics.

Don't know about trek, this frame is anodized aluminun with carbon fork. And only cables on this bike are the brake cables. The gear shifting is DI2 with the battery in the seat post. The brake cables and electrical wires are routed internally. For $5000 I would expect this bike to be free of corrosion, for a long time. Cannondale makes the best aluminun frames in the world, and if they can do such an amazing job with aluminum. I am sure apple can do the same with a watch made of aluminum, being the multi billion dollar company that they are. Having way more money than Cannondale.

 

[Mr. Buzzcut]

Don't know about trek, this frame is anodized aluminun with carbon fork. And only cables on this bike are the brake cables. The gear shifting is DI2 with the battery in the seat post. The brake cables and electrical wires are routed internally. For $5000 I would expect this bike to be free of corrosion, for a long time. Cannondale makes the best aluminun frames in the world, and if they can do such an amazing job with aluminum. I am sure apple can do the same with a watch made of aluminum, being the multi billion dollar company that they are. Having way more money than Cannondale.

I'm sure your bike is great as Canondale usually is, but that's not what is being discussed here. Your fork floats in the head tube with bearings and grease in between. The carbon Treks were also $5k bikes. And the contact was direct.

 

[Peepo]

Just throw some of that anti-oxidant paste on there used for copper to aluminum AC wiring connections and good to go.

 

[01silver4]

I'm sure your bike is great as Canondale usually is, but that's not what is being discussed here. Your fork floats in the head tube with bearings and grease in between. The carbon Treks were also $5k bikes. And the contact was direct.

Ok I will pull my carbon fork out and look for corrosion on the inside of the head tube. Even though I think the grease would prevent this. Will get back to u with the results.