polish clear coat on a carbon post?

[John Verheul]

Last fall a teammate borrowed one of my 'cross bikes, and it had to be
adjusted for him (lower seat height) very quickly, so the carbon post is now
completely scratched and scuffed. On any of my bikes, there are at least a
few cm showing of this scratched up section of post. My question is, how
can I polish/smooth the clear coat so that it doesn't look horrible? The
post is still fine, just the clear coat is really ugly. There are scuffs, as
well as some deeper scratches in it, but nothing that goes through the clear
coat to the carbon itself.

 

[bfd]

On Jun 25, 2:15 pm, "John Verheul" <[email protected]> wrote:
> Last fall a teammate borrowed one of my 'cross bikes, and it had to be
> adjusted for him (lower seat height) very quickly, so the carbon post is now
> completely scratched and scuffed. On any of my bikes, there are at least a
> few cm showing of this scratched up section of post. My question is, how
> can I polish/smooth the clear coat so that it doesn't look horrible? The
> post is still fine, just the clear coat is really ugly. There are scuffs, as
> well as some deeper scratches in it, but nothing that goes through the clear
> coat to the carbon itself.

For my carbon frame, standard operating procedure is to get yourself
some clear nail polish and just touch it up. Unless the scratch is
deep, in which case, you may want to have it inspected by a shop. Good
Luck!

 

[Robert Lorenzini]

On Mon, 25 Jun 2007 15:37:09 -0700, bfd <[email protected]> wrote:
> On Jun 25, 2:15 pm, "John Verheul" <[email protected]> wrote:
>> Last fall a teammate borrowed one of my 'cross bikes, and it had to be
>> adjusted for him (lower seat height) very quickly, so the carbon post is now
>> completely scratched and scuffed. On any of my bikes, there are at least a
>> few cm showing of this scratched up section of post. My question is, how
>> can I polish/smooth the clear coat so that it doesn't look horrible? The
>> post is still fine, just the clear coat is really ugly. There are scuffs, as
>> well as some deeper scratches in it, but nothing that goes through the clear
>> coat to the carbon itself.
>
> For my carbon frame, standard operating procedure is to get yourself
> some clear nail polish and just touch it up. Unless the scratch is
> deep, in which case, you may want to have it inspected by a shop. Good
> Luck!
>

I purchsed clear coat formulated for carbon fiber from a commercial
auto paint supply packaged in a spray can. In your case I think
you just need to polish with very fine paper 800 or < and finish
with compound. It will take a number of coats to repair chips
with this method but the repair will be totaly indistinguishable
from orig. My supplier was senikpaint.com in Costa Mesa CA but
should be avail locally.

Bob

 

[jim beam]

John Verheul wrote:
> Last fall a teammate borrowed one of my 'cross bikes, and it had to be
> adjusted for him (lower seat height) very quickly, so the carbon post is now
> completely scratched and scuffed. On any of my bikes, there are at least a
> few cm showing of this scratched up section of post. My question is, how
> can I polish/smooth the clear coat so that it doesn't look horrible? The
> post is still fine, just the clear coat is really ugly. There are scuffs, as
> well as some deeper scratches in it, but nothing that goes through the clear
> coat to the carbon itself.
>
>
nail polish. cheap. works great.

 

[Chris Nelson]

On Jun 25, 6:37 pm, bfd <[email protected]> wrote:
> On Jun 25, 2:15 pm, "John Verheul" <[email protected]> wrote:
>
> > Last fall a teammate borrowed one of my 'cross bikes, and it had to be
> > adjusted for him (lower seat height) very quickly, so the carbon post is now
> > completely scratched and scuffed. On any of my bikes, there are at least a
> > few cm showing of this scratched up section of post. My question is, how
> > can I polish/smooth the clear coat so that it doesn't look horrible? The
> > post is still fine, just the clear coat is really ugly. There are scuffs, as
> > well as some deeper scratches in it, but nothing that goes through the clear
> > coat to the carbon itself.
>
> For my carbon frame, standard operating procedure is to get yourself
> some clear nail polish and just touch it up. Unless the scratch is
> deep, in which case, you may want to have it inspected by a shop. Good
> Luck!

Curious, how does the shop perform an inspection?

Chris

 

[jim beam]

Chris Nelson wrote:
> On Jun 25, 6:37 pm, bfd <[email protected]> wrote:
>> On Jun 25, 2:15 pm, "John Verheul" <[email protected]> wrote:
>>
>>> Last fall a teammate borrowed one of my 'cross bikes, and it had to be
>>> adjusted for him (lower seat height) very quickly, so the carbon post is now
>>> completely scratched and scuffed. On any of my bikes, there are at least a
>>> few cm showing of this scratched up section of post. My question is, how
>>> can I polish/smooth the clear coat so that it doesn't look horrible? The
>>> post is still fine, just the clear coat is really ugly. There are scuffs, as
>>> well as some deeper scratches in it, but nothing that goes through the clear
>>> coat to the carbon itself.
>> For my carbon frame, standard operating procedure is to get yourself
>> some clear nail polish and just touch it up. Unless the scratch is
>> deep, in which case, you may want to have it inspected by a shop. Good
>> Luck!
>
> Curious, how does the shop perform an inspection?
>
usually, visually. other than having some experience, they're often not
in as good a position to judge as the owner if there's a problem.

damage to clearcoat means nothing structurally unless it causes
weathering and delamination. if the component has a layer of cosmetic
weave on the exterior, damage to that often that doesn't mean much
structurally either. the #1 thing to "look" out for is noise.
cracking, creaking or groaning noises [when isolated from fitting
issues] in carbon is a guaranteed problem - regardless of looks. if a
fork cracks and creaks when the blades are squeezed together for
instance, condemn it immediately. riders of carbon componentry should
be aware of this at all times.

 

[Bruce Gilbert]

"jim beam" <[email protected]> wrote in message
news:[email protected]...
> Chris Nelson wrote:
> > On Jun 25, 6:37 pm, bfd <[email protected]> wrote:
> >> On Jun 25, 2:15 pm, "John Verheul" <[email protected]> wrote:
> >>
> >>> Last fall a teammate borrowed one of my 'cross bikes, and it had to be
> >>> adjusted for him (lower seat height) very quickly, so the carbon post
is now
> >>> completely scratched and scuffed. On any of my bikes, there are at
least a
> >>> few cm showing of this scratched up section of post. My question is,
how
> >>> can I polish/smooth the clear coat so that it doesn't look horrible?
The
> >>> post is still fine, just the clear coat is really ugly. There are
scuffs, as
> >>> well as some deeper scratches in it, but nothing that goes through the
clear
> >>> coat to the carbon itself.
> >> For my carbon frame, standard operating procedure is to get yourself
> >> some clear nail polish and just touch it up. Unless the scratch is
> >> deep, in which case, you may want to have it inspected by a shop. Good
> >> Luck!
> >
> > Curious, how does the shop perform an inspection?
> >
> usually, visually. other than having some experience, they're often not
> in as good a position to judge as the owner if there's a problem.
>
> damage to clearcoat means nothing structurally unless it causes
> weathering and delamination. if the component has a layer of cosmetic
> weave on the exterior, damage to that often that doesn't mean much
> structurally either. the #1 thing to "look" out for is noise.
> cracking, creaking or groaning noises [when isolated from fitting
> issues] in carbon is a guaranteed problem - regardless of looks. if a
> fork cracks and creaks when the blades are squeezed together for
> instance, condemn it immediately. riders of carbon componentry should
> be aware of this at all times.

Well said, sir!
Bruce

 

[DirtRoadie]

Robert Lorenzini wrote:
> I purchsed clear coat formulated for carbon fiber from a commercial
> auto paint supply packaged in a spray can. In your case I think
> you just need to polish with very fine paper 800 or < and finish
> with compound. It will take a number of coats to repair chips
> with this method but the repair will be totaly indistinguishable
> from orig. My supplier was senikpaint.com in Costa Mesa CA but
> should be avail locally.

My variation (all materials available from a hardware store) -
If a recoat is necessary use gloss polyurethane varnish (water borne).

Wet sand the bad area (200-400#) to smooth out /remove scratches.
Spray or brush on the polyurethane. Avoid thick coats.
After sufficient drying time, wet sand again using progessively finer
grits up to 600/800 or so.
Repeat with additional coats if necessary, especially if there are
areas (chips) that need to be built up.

Rottenstone rubbing powder is great for the finish polishing.
Automotive rubbing compunds tend to be a little too aggressive.

As described by the poster above, the finish will look like new.

DR

 

[Chris Nelson]

On Jun 26, 8:59 am, jim beam <[email protected]> wrote:
> Chris Nelson wrote:
> > On Jun 25, 6:37 pm, bfd <[email protected]> wrote:
> >> On Jun 25, 2:15 pm, "John Verheul" <[email protected]> wrote:
>
> >>> Last fall a teammate borrowed one of my 'cross bikes, and it had to be
> >>> adjusted for him (lower seat height) very quickly, so the carbon post is now
> >>> completely scratched and scuffed. On any of my bikes, there are at least a
> >>> few cm showing of this scratched up section of post. My question is, how
> >>> can I polish/smooth the clear coat so that it doesn't look horrible? The
> >>> post is still fine, just the clear coat is really ugly. There are scuffs, as
> >>> well as some deeper scratches in it, but nothing that goes through the clear
> >>> coat to the carbon itself.
> >> For my carbon frame, standard operating procedure is to get yourself
> >> some clear nail polish and just touch it up. Unless the scratch is
> >> deep, in which case, you may want to have it inspected by a shop. Good
> >> Luck!
>
> > Curious, how does the shop perform an inspection?
>
> usually, visually. other than having some experience, they're often not
> in as good a position to judge as the owner if there's a problem.
>
> damage to clearcoat means nothing structurally unless it causes
> weathering and delamination. if the component has a layer of cosmetic
> weave on the exterior, damage to that often that doesn't mean much
> structurally either. the #1 thing to "look" out for is noise.
> cracking, creaking or groaning noises [when isolated from fitting
> issues] in carbon is a guaranteed problem - regardless of looks. if a
> fork cracks and creaks when the blades are squeezed together for
> instance, condemn it immediately. riders of carbon componentry should
> be aware of this at all times.- Hide quoted text -
>
> - Show quoted text -

Alllrighty then. I will be adding the creak and groan check to my
preride ritual on my one and only carbon device, the fork, ironically,
the last place you want material failure. After ride launch, these
sounds are more likely to come from the engine room.

Chris

 

[Camilo]

On Jun 25, 1:15 pm, "John Verheul" <[email protected]> wrote:
> Last fall a teammate borrowed one of my 'cross bikes, and it had to be
> adjusted for him (lower seat height) very quickly, so the carbon post is now
> completely scratched and scuffed. On any of my bikes, there are at least a
> few cm showing of this scratched up section of post. My question is, how
> can I polish/smooth the clear coat so that it doesn't look horrible? The
> post is still fine, just the clear coat is really ugly. There are scuffs, as
> well as some deeper scratches in it, but nothing that goes through the clear
> coat to the carbon itself.

John, without looking at your post, I can't say what of the advice
others have given you will be best. But in my mind (and based on my
experience), the scuffs caused by lowering, then raising a seat post
will not be effectively made to look nicer with nail polish. Nail
polish could possibly help if there were individual, distinct
scratches.

What I would do is this: I would treat it as I would superficial
scuffs on any glossy painted surface: I'd first try a fine car polish
(polish, not wax). If that didn't work, I'd try something a little
coarser such as a very fine rubbing compound, followed by the first-
mentioned polish. In other words, go as "rough" as you need to with
some sort of rubbing compound, following with finer polishing
compounds. In my garage I must have 3 grades of rubbing compound,
regular car polish, and three or four different pruducts for polishing
plastic. The plastic stuff is also grit-based, just much finer and
the grit is designed for polishing plastic windows instead of paint.

Auto parts stores have individual and "families" of products that are
designed for this sort of progressive scratch removal. Maguires is one
example. But...

If you're convinced there is no structural issues, a suggestion would
be to take the post to a shop that specializes in automobile finishes
(they are common) and just ask them what they'd recommend. Worst case
(IMHO) is that you'd lightly sand the entire post with VERY FINE sand
paper enough to make the scuffed areas indistinct from the rest of the
post (which you have also sanded) and then refinish with clear coat.
Again, a specialty shop could advise you on that.

 

[Johnny Sunset]

On Jun 25, 4:15 pm, John Verheul wrote:
> Last fall a teammate borrowed one of my 'cross bikes, and it had to be
> adjusted for him (lower seat height) very quickly, so the carbon post is now
> completely scratched and scuffed. On any of my bikes, there are at least a
> few cm showing of this scratched up section of post. My question is, how
> can I polish/smooth the clear coat so that it doesn't look horrible? The
> post is still fine, just the clear coat is really ugly. There are scuffs, as
> well as some deeper scratches in it, but nothing that goes through the clear
> coat to the carbon itself.

If it were my bike, I would just cover the scratched area with tape,
or some sort of decal that wraps all the way around. For example, it
may well be possible to do the national colors of the country of
origin of the bicycle with electrical tape.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful

 

[wizardB]

John Verheul wrote:
> Last fall a teammate borrowed one of my 'cross bikes, and it had to be
> adjusted for him (lower seat height) very quickly, so the carbon post is now
> completely scratched and scuffed. On any of my bikes, there are at least a
> few cm showing of this scratched up section of post. My question is, how
> can I polish/smooth the clear coat so that it doesn't look horrible? The
> post is still fine, just the clear coat is really ugly. There are scuffs, as
> well as some deeper scratches in it, but nothing that goes through the clear
> coat to the carbon itself.
>
>
Ride more worry less