how thick is the tubing of an aluminum frame, specifically the chainstay tube? i scraped it hard on a curb, and it scratched a pretty thick chunk out of the tube. no dent, but a deep gash. should i be worried? it's a Specialized road frame built in 2004, in case that info helps (Specialized Langster to be exact). i'm not sure exactly how deep, but i'll try to measure it when i get a chance.