When is a scratch actually a crack?

moonio
moonio Posts: 802
edited September 2009 in Commuting chat
I have a deep scratch in my bikes top tube and i cant tell if its actually a crack, this is what the frame is made of
''Hand built 6061 Alloy Tr and T6 tempered,
Diamond metallic black baked 3 coats.'

and I think it has a lifetime guarantee.

if its just a scratch can I cover it with a few coats of clear nail lacquer to keep water etc out??

Comments

  • whyamihere
    whyamihere Posts: 7,714
    If it's just a scratch, then there's no need to keep water out, it's not going to rust or anything.
  • What saddle are you using?
  • moonio
    moonio Posts: 802
    Why? Its just the one that came with the bike, kinda wide and springy with a suspension seat post..
  • moonio
    moonio Posts: 802
    whyamihere wrote:
    If it's just a scratch, then there's no need to keep water out, it's not going to rust or anything.
    Why wont it rust?
  • whyamihere
    whyamihere Posts: 7,714
    No, only steel rusts. Your frame's aluminium. Aluminium corrodes, but the way it does so builds up a protective layer that stops it from corroding further, and the corrosion doesn't weaken the frame to any noticeable extent.
  • moonio wrote:
    whyamihere wrote:
    If it's just a scratch, then there's no need to keep water out, it's not going to rust or anything.
    Why wont it rust?
    Because its aluminium. Actually, it rusts almost immediately, but won't rust any more.
  • whyamihere wrote:
    No, only steel rusts. Your frame's aluminium. Aluminium corrodes, but the way it does so builds up a protective layer that stops it from corroding further, and the corrosion doesn't weaken the frame to any noticeable extent.
    There's an Einstein quote, about teaching, which you should read.
    :D
  • whyamihere
    whyamihere Posts: 7,714
    whyamihere wrote:
    No, only steel rusts. Your frame's aluminium. Aluminium corrodes, but the way it does so builds up a protective layer that stops it from corroding further, and the corrosion doesn't weaken the frame to any noticeable extent.
    There's an Einstein quote, about teaching, which you should read.
    :D
    I'm fully aware of it, but I'm far too tired to simplify things or make an analogy right now. ;)
  • fossyant
    fossyant Posts: 2,549
    Just blob some paint on it - like car touch up, otherwise it will just 'bubble' the paint off the aluminium if left.

    Cosmetic really, but it will soon look a mess if you don't. Steel rusts, but a quality steel frame will just surface rust, much like alloy will bubble the paint - Crap steel frames will rust to bits, but a Reynolds or Columbus one won't...

    Mostly aesthetics....... look after it....otherwise it will look tatty...
  • moonio
    moonio Posts: 802
    whyamihere wrote:
    No, only steel rusts. Your frame's aluminium. Aluminium corrodes, but the way it does so builds up a protective layer that stops it from corroding further, and the corrosion doesn't weaken the frame to any noticeable extent.

    Ahh, for some reason I thought it was a steel frame...