Cracks?

[Paul]

Whilst cleaning my bike and checking for cracks I've noticed a couple of small pits (the largest is
only pin head sized). They occur in the middle of the two welds where the chainstays are welded to
the bottom bracket. You can see the oxidise aluminum in these pits although they don't appear to be
cracks, just dimples where the two welds met that didn't get paint on them.

I've put a drop of clear car paint lacquer on as I do for all scratches on my bike but I was
wondering whether there is any cause for concern.

I tend to get a bit obsessive about looking for cracks after hearing that alloy bikes can crack but
I'm probably over reacting and aluminium frames are probably quite sound. The frame is 7005 T6
(plain guage) and under a year old.

Thanks for any thoughts, Paul.

 

[Paul Southworth]

In article <[email protected]>, Paul <[email protected]> wrote:
>Whilst cleaning my bike and checking for cracks I've noticed a couple of small pits (the largest is
>only pin head sized). They occur in the middle of the two welds where the chainstays are welded to
>the bottom bracket. You can see the oxidise aluminum in these pits although they don't appear to be
>cracks, just dimples where the two welds met that didn't get paint on them.
>
>I've put a drop of clear car paint lacquer on as I do for all scratches on my bike but I was
>wondering whether there is any cause for concern.

No.

>I tend to get a bit obsessive about looking for cracks after hearing that alloy bikes can crack but
>I'm probably over reacting and aluminium frames are probably quite sound. The frame is 7005 T6
>(plain guage) and under a year old.

It's a good idea to regularly inspect all bicycle frames. This is not over reacting - every kind of
bicycle can be broken.

--Paul

 

[Tony Raven]

If you are really worried pop down to a local engineering shop. They have a special liquid and UV
lamp that will confirm whether there are any cracks. You are probably worrying too much though

Tony

--
http://www.raven-family.com

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer

In news:[email protected], Paul <[email protected]> typed:
> Whilst cleaning my bike and checking for cracks I've noticed a couple of small pits (the largest
> is only pin head sized). They occur in the middle of the two welds where the chainstays are welded
> to the bottom bracket. You can see the oxidise aluminum in these pits although they don't appear
> to be cracks, just dimples where the two welds met that didn't get paint on them.
>
> I've put a drop of clear car paint lacquer on as I do for all scratches on my bike but I was
> wondering whether there is any cause for concern.
>
> I tend to get a bit obsessive about looking for cracks after hearing that alloy bikes can crack
> but I'm probably over reacting and aluminium frames are probably quite sound. The frame is 7005 T6
> (plain guage) and under a year old.
>
> Thanks for any thoughts, Paul.

 

[Jon Bond]

"local engineering shop"... not too sure what to look for, and it'd be nice to know about my little
cratch/scrack there before I send it away for a month! Do you mean either an autoshop type place or
a company that does machining that wouldn't mind taking a few minutes to check?

Thanks!

Jon Bond

"Tony Raven" <[email protected]> wrote in message
news:[email protected]...
> If you are really worried pop down to a local engineering shop. They have
a
> special liquid and UV lamp that will confirm whether there are any cracks. You are probably
> worrying too much though
>
> Tony
>
> --
> http://www.raven-family.com
>
> "All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
> Finally, it is accepted as self-evident." Arthur Schopenhauer
>
>
>
> In news:[email protected], Paul <[email protected]> typed:
> > Whilst cleaning my bike and checking for cracks I've noticed a couple of small pits (the largest
> > is only pin head sized). They occur in the middle of the two welds where the chainstays are
> > welded to the bottom bracket. You can see the oxidise aluminum in these pits although they don't
> > appear to be cracks, just dimples where the two welds met that didn't get paint on them.
> >
> > I've put a drop of clear car paint lacquer on as I do for all scratches on my bike but I was
> > wondering whether there is any cause for concern.
> >
> > I tend to get a bit obsessive about looking for cracks after hearing that alloy bikes can crack
> > but I'm probably over reacting and aluminium frames are probably quite sound. The frame is 7005
> > T6 (plain guage) and under a year old.
> >
> > Thanks for any thoughts, Paul.

 

[Tony Raven]

In news:NwQEa.913255$Zo.209126@sccrnsc03, Jon Bond <[email protected]> typed:
> "local engineering shop"... not too sure what to look for, and it'd be nice to know about my
> little cratch/scrack there before I send it away for a month! Do you mean either an autoshop type
> place or a company that does machining that wouldn't mind taking a few minutes to check?
>
> Thanks!
>
> Jon Bond

Place that does machining of metals. If you have a Mechanical Engineering School at Tufts they can
probably do it for you.

Tony

--
http://www.raven-family.com

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer

 

[Jon Bond]

"Tony Raven" <[email protected]> wrote in message
news:[email protected]...
> In news:NwQEa.913255$Zo.209126@sccrnsc03, Jon Bond <[email protected]> typed:
> > "local engineering shop"... not too sure what to look for, and it'd be nice to know about my
> > little cratch/scrack there before I send it away for a month! Do you mean either an autoshop
> > type place or a company that does machining that wouldn't mind taking a few minutes to check?
> >
> > Thanks!
> >
> > Jon Bond
>
> Place that does machining of metals. If you have a Mechanical Engineering School at Tufts they can
> probably do it for you.
>
> Tony

I'm in the Mech E. school Unfortunately, being summer, I'm not at Tufts, which is why I was
wondering where to find some here in boring ol' CT!

Thanks!

Jon Bond