XxHaimBondxX

Picked this up for parts, but hard to believe this is all it takes to salvage a carbon frame. Looks like something fell on the top tube, chipping and cracking the paint, still not a crash. Any way to save this?

grumpus

Hard to tell from the pictures, I'd chip off as much paint as I could to get a better view of the carbon: lighter lines equals delamination, but there could be other damage you can't see - it needs an ultrasound scan. Any carbon frame is fixable if you spend enough, but often not really worth it. This is the price you pay for high performance plastic - that ding in a steel frame would just be annoying.

icemilkcoffee 

Just like with any boat hull or any other composite object: use a hard object to tap along the carbon top tube. It should have a hard crisp knock to it. When you get to that chipped section, does the tone change? If there is no change in tone then I would say it's totally fine. If it turns into a thud then there is de-lamination.

Andrew R Stewart 

If the frame construction allows a borescope up inside the tube I would suggest that as an inspection method that shouldn't cost too much. (I know a couple of auto body work guys that use them for unibody inspections).

The tapping the surface with a hard object is ok but the paint can delam. from the structural carbon and you'll just feel that change. I agree with grumpus's suggestion of removing paint to better see/tap the structural carbon.

There are a number of outfits that fix carbon bike frames. Most will provide a starting assessment via photos in an email and modify as needed when they get hands on. Most likely will also offer paint touch up services (were I them I would only offer repairs that also included the paint work). Costs from a few hundred $ and up are typical (not including shipping).

XxHaimBondxX

Great idea, I have one, and finally reason to put it to use.

squirtdad

hard to tell, but it appear to be a serious hit that caused frame to deform in a good sized area with all the paint chips and all. I think I see some fiber ends, but not sure

all in all seems a bit suspect

if is it a good frame expect 300 to 600+ for a repair

I have not used any of these, but the calfee is well known.... the first two are near me san jose, santa cruz area the third in Minnesota and the last might of interest to OP XxHaimBondxX in that it is in NY State just up the road from albany

https://calfeedesign.com/carbon-repair/

https://www.spydercomposites.com/faqs

https://www.applemanbicycles.com/repair/

https://carbonbikespecialists.com/?useYB=1

FBinNY 

The paint cracks are a good indication of compromised CF structure, but indications are more by way of warning than proof.

Paint is often more brittle than and cannot flex as much as the thin structure they cover. If you can flake off more paint you might be able to verify whether there's visible damage to the CF or, more commonly, the matrix holding it together. Sometimes, if you have well calibrated fingers, you can tell by gently squeezing the area and a comparable one nearby feeling for a softer spot. As noted, the tap test may also offer clues.

However, while it's easy to confirm damage, there is virtually no way to confirm that a CF structure is undamaged, shy of expensive testing methods. So, the best you can hope for is either positive confirmation that it's toast, or accepting that it seems OK and deciding whether seems OK is good enough.

grumpus

Reminds me of my boat building days - a company I briefly worked for built commercial fishing boats, in order to be eligible for a government grant they required clear gelcoat below the waterline. Some genius started a layup with full coloured gelcoat, not just above the waterline, and nobody thought to question this until they opened the mould to find ... a hull they couldn't sell. Fortunately I soon found employment with a less stupid outfit.

base2 

It's hard to tell exactly what kind of bike this is. My spide-y sense tells me it is the result of high impact with a handlebar or perhaps the full force of a fall over against a post or similar at just the right distance to nearly wedge before stopping. (I once had that exact situation with an aluminum top tube.)

In any case, what you have is pretty darn rare in spite of what the crabon-plastique detractors will suggest.

When I wedged a cadence sensor between the thinnest midspan portion of the chain stay and the crank arm. The tap test told me is was damaged. I still rode it for months until a bubble formed. Ruckus Composites repaired it including factory paint for ~$800.

Worth every penny. Seamless and indistinguishable...Well, I can tell because I know the area and how to actually perform the repair. But, nobody else can tell & the frame was worth the cost to me to have it professionally done.

Carbon can be repaired effectively as many times as needed in whatever manner needed with out loss of performance. The question is always cost. For the Cervelo, with factory paint, $800 was a no-brainer. A standard $5-600 repair with flat-black paint would've sucked too much value from the bike on account of the repair being both obvious and ugly.

If the frame is worth $5-600 and all the trouble to box/ship/etc... to you, go for it.

Iride01 

It isn't a big deal. A person that has the skills can fix that carbon fiber just as someone that has the skills to braze on a steel bike. What is a big deal is finding those people that have the skills. They are out there. But they'll probably want more for that repair than you'll want to pay. Just like most people that braze will probably want more to replace a tube on a bike than you'll be willing to pay. But if you have any skills with glass work for things made of fiber glass, you can probably figure out and get the stuff you need to do a decent repair on CF yourself.

Though depending on the extent of the damage, it might not be worth the time and effort.

TiHabanero

Last year I acquired a Giant OCR frame that had a heavy tube fall on the top tube and crushed the carbon. I was able to flex the tube in that area with my fingers and the tap test with a quarter also showed damage. Although have never worked with carbon I did the repair myself with carbon fabric procured from Amazon. Turned out fine structurally, but cosmetically it was ugly! I gave it to a guy who is still riding it.

Mad Honk 

In my mind this frame is done. What we found out at Indy Car when CF first came out they tested it with a sledge hammer. And the results found spider cracks in the tub after the testing. So I would suspect the same here. I normally do work with CF golf shafts as a Golf Equipment Professional, and any damage like this would test my liability insurance if I let it back out into the wild. If anyone wants to try to save it I would give caution about further failure. One of those ride at your own risk cases. JMHO, MH

ScottCommutes

"Percussive evaluation"

Koyote

Looks like paint damage. I'd still be riding it.

cf is not as fragile as people like to believe.

GamblerGORD53

Since you bought it for scrap there is NO reason to fix it. It looks like it's 15 or 20 years old at least anyway. The tube looks mostly round, old design.
The whole white part looks dented to me.

Duragrouch

Disclaimer: Everything is at your own risk.

I would first check softness with thumb, compared to surroundings. Soft? Fail. Still feels rigid? Proceed to next test.

Tap test like others have said. Sound OK?

Borescope would be good, to see if cracks extend to inside the tube.

Then I would carefully chip off paint, examine, then touch up the paint. But perhaps not if it passes all above tests.

Part of the reason I am saying the above is that the top tube is not the highest stressed part of the frame, and that's a pretty fat tube. That kind of damage on skinny chainstay or seatsay, would be more critical. Not saying the above is "fine", but you have a bit more margin.

What style of bike is it? Road? Mountain? Downhill?

XxHaimBondxX

Sorry forgot to mention, it's a Bianchi Vertigo with 105 components, appears around 2014. I don't think it's worth repairing either to flip or ride (too small). I was planning to acquire a gravel frame and stick fatter tires on those wheels or sell parts. I drive past CK Bicycles every day, which is one of repair facilities squirtdad mentioned, hoping they can scan it for little money.

CrimsonEclipse

What's the price of the frame failing?
Are you willing to pay that price?

I know of only a few people I'd trust with repairing CF.
And they would tell me to get a new frame.

wheelreason

Inhaling resin will do that... My 23 SeaCraft was one color from keel to gunnel with no water line.

zandoval 

Years ago we used this method with Poles used in Pole Vaulting. It was a good indicator of wear and tear. Often a weak area was identified that did not even have visible exterior damage.

I dont know if its practical but thinking more along this line it might be a good idea to ping/thump your new carbon bikes and get familiar with thier sound. That way you could identify changes latter on.

I dont know if people already do this...

Note: My backyard DIY repair of this injury would be to strip the paint and after close inspection graft on a long aluminum sleeve over the tube.

choddo

I had similar damage in a chainstay fixed by the guys at Carbon Bike Repair who pop up on youtube from time to time. £300. Another 300 for paint. £50 each end to remove and redo all cabling. Completely invisible but the bike was worth a lot more than this one.

CrimsonEclipse

I'll skip the lecture on CF and simply state: exercise extreme caution.

grumpus

I caught a faceful of resin one day, at a different boatbuilder - we had no PPE issued except gloves. Inhaling glass fibres wasn't the smartest thing to do either, that stuff got everywhere.

wheelreason

Oh, I know the type, while in the Navy, when the ship pulled into the yards for maintenance one time, 3 of us from deck were "lent" to the boat maintenance "shack" led by a salty old civilian who didn't even know what PPE was, we were there to refurbish our 2 boats, but he had us doing all sorts of things, learned a lot, but went out and bought me a rtespirator, and other PPE for the second day. Turned out well, as the guys on the ship were getting off around 4-6 pm, we left much earlier, and had most Fridays off. Not a bad 3 months, and now I can roll awlgrip with the best of them.

choddo

Aye. You definitely have to repair it properly.

I just found this by mistake funnily enough, these are the guys who fixed mine