Good point about manufacturing defects, and absolutely correct.
I have heard of (but not seen in person) an occasional Campy or other brand of crankarm that failed at a void in the forging, for example. I believe it happened, but was probably extremely rare.
Maybe the black line on the Paletti's crankarm crack is dirt/grease? Look at the rest of the bike. That one looks like it has been "ridden hard and put away wet" as the motorcycle folks say.
Greg "going back to take another look at that jpeg" Parker A2 MI USA
In a message dated 5/16/02 3:16:33 PM Eastern Daylight Time, email@example.com writes:
> Message: 3
> Date: Thu, 16 May 2002 09:29:13 -0700
> From: Steve Maas <firstname.lastname@example.org>
> To: email@example.com
> Subject: Re: [CR]Campag crank cracking, etc...
> Regarding the cracked crank, that is, if you can stand one more opinion...
> I noticed that there is a black line on the back of the spider, above
> the crack. Looks like someone noticed it and marked it at one point. If
> so, the line/crack appears to lead to the spindle. Maybe the spindle or
> mating taper in the crank are bunged up (to use a technical term), and
> someone overtightened it to keep it from coming loose?
> Also, there is another possibility I haven't heard in all the talk of
> failing parts, not just crank arms. Parts sometimes break because of
> flaws in manufacturing. It happens. That's why high-reliability
> hardware, whether mechanical or electronic, undergoes special
> manufacturing and testing.
> Steve Maas