On May 10, 8:39=A0am, "Paul M. Hobson" <fob...@[EMAIL PROTECTED]
> wrote:
> http://www.flickr.com/photos/p_myron_h/2480606432/sizes/l/
>
> You'll see a silver Velocity Aerohead rim. =A0According to the builder,
> the rim was stress relieved (JB's method) and tensioned to 100 - 110
> kgf. =A0On both sides of each spoke hole, the aluminum appears to be
under=
> significant stress by the discoloration (lighter color).
>
> Capturing this with a photograph was tough as the lighting has to be
> just right to notice it even with the wheel in front of you. =A0In the
> photo, you can only see it at the left and middle holes, but this is
> happening at all 32 holes.
>
> Is this normal? =A0Scary? =A0Immediately dangerous? =A0To me, it seems
to
> indicate that there's a bit too much tension in the spokes. =A0But I'm
> definitely among the uninitiated when it comes to wheel building -- all
> of my rims up to this point have been anodized black, =A0which might be
> hiding this from me.
>
> FWIW, the wheel has taken a good bit of abuse already and still quite
true=
..
>
> Thanks,
> \\paul
> --
> Paul M. Hobson
> .:change the f to ph to reply:.
Basically, this is normal, you can keep using the wheel.
This is a known issue with Velocity Aerohead rims. The valley inside
the rim is too narrow for many spoke nipple heads, so the rim bulges
and crazes the anodizing. Typically, with use you might eventually get
little cracks emanating laterally from the edges of the spoke holes.
These cracks seem to relieve the outward stress in the rim and usually
grow to about a millimeter or two in length. Eventually they reach a
stable length and don't get any bigger, even with more use. Maybe it's
the substantial cir***ferential compressive stress that keeps them
from growing...
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