Crack in Frame

[MaxPrime]

I've been riding an aluminum frame for two years now. I looked at it while cleaning it today and the paint is cracked (not scratched) in one place along the downtube. How do I tell if this is a surface paint crack or a metal crack? Thanks.

 

[packmagician]

I've been riding an aluminum frame for two years now. I looked at it while cleaning it today and the paint is cracked (not scratched) in one place along the downtube. How do I tell if this is a surface paint crack or a metal crack? Thanks.

One way is to use a sharp knife or razor blade to scrape away the paint in a small area over the suspected crack.

 

[awiner]

Obviously X-ray machines aren't available to most of us, but if you know someone that has access to such a machine you could X-ray it.

 

[Fat Hack]

I've been riding an aluminum frame for two years now. I looked at it while cleaning it today and the paint is cracked (not scratched) in one place along the downtube. How do I tell if this is a surface paint crack or a metal crack? Thanks.

Yeah, you've gotta get the paint off. This happened to me.

I scratched the top stuff off, then sanded, then used steel wool to smooth out the alu to make sure it wasn't a scratch, but it wasn't. I kept buffing and buffing with the steel wool, hoping that the crack would disappear, but it didn't.

In my experience, if there's a crack in the frame, the paint movement looks like a miniature fault line