Why are some of the SR/NR parts anodized and some are not?
If you read my previous post (repro'd below) you'll see that there would seem to be no reason not to anodize all the aluminum parts in the group. All advantages and no disadvantages, right? Anodizing is not, BTW, a good bearing surface, does not increase the strength of aluminum part, and resists scratching but only to a very small degree.
There are only a few parts that aren't anodized: Seat post, pedal bodies, hubs, shift levers, and front derailleur body and arms.
My educated guess? If the part is likely to get scratched (or worn) it was not anodized. If an anodized part gets scratched your only recourse is to strip the anodizing, polish out the scratch and then reanodize the part. If the part is not anodized and gets scratched, you just polish the part and it looks good again.
The seat post and pedal bodies are the prime example of parts that get badly scratched (seat post by insertion, and the pedal body by being kicked and stepped on to flip right side up) and can be made to look good again by polishing.
So why are hubs not anodized (they are not subject to scratching after all)? The story I heard was that the pro mechanics liked to be able to shine them up (shinier than you get with anodizing) as a matter of pride.
Shift levers? Maybe all the raised bumps and letters would get quickly worn through with all the hand contact of shifting? But the brake levers get a lot of handling too and are anodized. Don't know.
The front derailleur body and arms? Don't know. You'd think it would be anodized to match the rear derailleur but it isn't.
One last point: The cranks are anodized, but not because it keeps them from galvanic fusing onto the BB axle as was stated in a previous post. Anodizing will not occur inside a hole for the same reasons you cannot chrome plate inside a hole unless you use special fixturing. Examining the interface between the axle and the crank will show that there is no barrier such as anodizing (which wouldn't hold up anyway actually).
Please let's hear your theories...
Chuck Schmidt South Pasadena, CA
Old post: ======================================================================== Date: Mon, 17 Feb 2003 19:47:41 -0700 From: Chuck Schmidt <chuckschmidt@earthlink.net> Subject: [CR]Campagnolo Nuovo Record and Super Record anodizing
There seems to be lots of confusion on just which aluminum parts in a Nuovo or Super Record are anodized. This comes up when questions about how best to clean the parts when finding an old bike.
First, some anodizing info...
Definition: Anodizing is the successful development and control of a natural oxidation process that occurs when aluminum is exposed to the atmosphere. Electricity and chemicals are used jointly to produce a hard, transparent surface that is integral with base aluminum.
Anodizing Basics: Aluminum is anodized for corrosion resistance, abrasion resistance, insulation from electricity, adhesion, or aesthetic enhancement.
Characteristics: Hard, comparable to a sapphire Transparent, similar to glass Insulative and static-resistant Wide variety of colors and finishes Integral with aluminum surfaces, non-flaking
Now, which aluminum parts are anodized and which aren't:
Hubs - no Pedal bodies - no Pedal cages - yes Headset - yes Rear derailleur - yes Front derailleur - no Cranks - yes Chainrings - yes Brake levers - yes Brake calipers - yes Shift levers - no Seat post - no
Incidentally, when the Super Record group first made the rounds of the trade shows circuit, the head set, chainrings, and bottom bracket cups were black anodized. The production versions were clear anodized.
The non anodized parts can be cleaned and polished (and protected) with Semichrome, Wenol, Mothers, etc.
The anodized parts can be cleaned with degreaser, solvent, WD-40, soap and hot water, etc.
A simple test to see if an aluminum part is anodized or not. Put a little dab of Semichrome (my personal favorite) on a white cloth and rub the part a little. If there is a black deposit on the cloth that means that there has been a chemical reaction with the aluminum. If the part is anodized, there will be no change in the polish on the cloth because there has been no reaction (and absolutely no damage to the anodizing).
Now the QUESTION: Why are some of the parts anodized and some are not? Class? Anyone?
Chuck Schmidt South Pasadena, Southern California http://www.velo-retro.com (Campagnolo Timeline, reprints & t-shirts)
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